SYSTEMS AND METHODS FOR PRODUCING TEXTURIZED CASTING MOLDS OF A CONTINUOUS BELT CASTER

FIELD OF THE INVENTION

This application relates to continuous belt casters, and, more specifically, to systems and methods for producing texturized casting molds of continuous belt casters.

BACKGROUND

Continuous belt casters, such as twin belt casters, single belt casters, and recirculating block casters, are commonly used to produce cast metal articles from molten metal including but not limited to aluminum and aluminum alloys. In continuous belt casters, a casting cavity is formed between continuously moving casting surfaces. During the casting process, molten metal is introduced into the casting cavity (typically on a continuous basis). Heat is removed from the metal by the elongated belt surfaces and the metal solidifies into the metal article, which is continuously withdrawn from the casting cavity by the moving casting surfaces.

A texture on the elongated belt surfaces, such as steel belt surfaces or copper belt surfaces, may at least partially affect the heat flux through the elongated belt surfaces. For steel belts, the traditional procedure for texturizing the belt surfaces is done by a controlled shot-blasting process in which steel shot (or other media) is mixed with air and pressurized using a cyclone, and the shot is fired through a gun at the belt surface to induce surface textures that are dimples with interconnected rims. The final texture depends on the shot size distribution, pressure, transverse speed, belt rotation speed, distance between the gun and the belt, and angle of incidence of the gun. Although shot-blasting is relatively economical and fast, the resulting texture is randomized and is difficult to repeat or precisely control to provide a specific texture, which may allow for metallurgical and mechanical surface defects and structural anisotropy in the as-cast metal article.

SUMMARY

Embodiments covered by this patent are defined by the claims below, not this summary. This summary is a high-level overview of various embodiments and introduces some of the concepts that are further described in the Detailed Description section below. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used in isolation to determine the scope of the claimed subject matter. The subject matter should be understood by reference to appropriate portions of the entire specification of this patent, any or all drawings, and each claim.

According to some embodiments, a method of texturizing a casting mold of a continuous belt casting system includes providing at least one endless belt with an elongated belt surface. The elongated belt surface includes at least a first region and a second region adjacent to the first region across a width of the elongated belt surface, and the elongated belt surface is configured to at least partially define a casting cavity of the continuous belt casting system. The method includes texturizing the elongated belt surface by applying a predetermined texture to the first region and such that the second region does not comprise the predetermined texture.

According to certain embodiments, a method of texturizing a casting mold of a continuous belt casting system includes providing at least one endless belt with an elongated belt surface. The elongated belt surface includes a first region and a second region adjacent to the first region across a width of the elongated belt surface, and the elongated belt surface is configured to at least partially define a casting cavity of the continuous belt casting system. The method includes locally texturizing the elongated belt surface such that the first region comprises a predetermined texture and the second region does not comprise the predetermined texture.

According to various embodiments, a method of texturizing a casting mold of a continuous belt casting system includes providing at least one endless belt with an elongated belt surface. The elongated belt surface includes a plurality of first regions and a plurality of second regions, and adjacent first regions are separated by one of the plurality of second regions. The elongated belt surface is configured to at least partially define a casting cavity of the continuous belt casting system. The method includes texturizing the elongated belt surface by applying a predetermined texture only to the first regions and such that a distance between adjacent first regions is from 0.01 mm to 1.0 mm, or any practical distance useful for casting purposes.

According to some embodiments, a continuous belt casting system includes an endless belt with an elongated belt surface, and the elongated belt surface includes a predetermined texturized pattern defined in the elongated belt surface. The elongated belt surface at least partially defines a casting cavity of the continuous belt casting system.

According to certain embodiments, a method of casting a metal slab includes introducing molten metal into a casting cavity defined by two endless belts, where at least one of the endless belts includes a belt surface with a predetermined texturized pattern. The method includes advancing the molten metal through the casting cavity by advancing the endless belts and such that the molten metal solidifies, and causing the solidified molten metal to emerge from an exit of the casting cavity as a metal slab and such that the as-cast metal slab includes a surface texture pattern corresponding to the texturized pattern of the belt surface.

According to some embodiments, an as-cast metal slab is formed by a continuous belt caster and includes a slab surface with a surface texture pattern corresponding to a predetermined texturized pattern on a belt surface of an endless belt of the continuous belt caster.

According to various embodiments, a method of texturizing a casting mold of a continuous belt casting system includes providing at least one endless belt comprising an elongated belt surface. The method includes texturizing the elongated belt surface by applying a predetermined texture pattern to the elongated casting, the predetermined texture pattern including a non-random pattern of grooves or ridges.

Various implementations described herein may include additional systems, methods, features, and advantages, which cannot necessarily be expressly disclosed herein but will be apparent to one of ordinary skill in the art upon examination of the following detailed description and accompanying drawings. It is intended that all such systems, methods, features, and advantages be included within the present disclosure and protected by the accompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The specification makes reference to the following appended figures, in which use of like reference numerals in different figures is intended to illustrate like or analogous components.

FIG. 1 illustrates a continuous belt casting system according to embodiments.

FIG. 2 is a flow chart of a method of preparing a casting surface of a continuous belt casting system according to embodiments.

FIG. 3 is a top view of an endless casting belt of a belt casting system prior to texturizing according to embodiments.

FIGS. 4A-C illustrate stages of a method of texturizing a casting surface for a continuous belt casting system according to embodiments.

FIGS. 5A-C illustrate stages of a method of texturizing a casting surface for a continuous belt casting system according to embodiments.

FIGS. 6A-B illustrate stages of a method of texturizing a casting surface for a continuous belt casting system according to embodiments.

FIGS. 7A-B illustrate stages of a method of texturizing a casting surface for a continuous belt casting system according to embodiments.

FIGS. SA-C illustrate a texturing device configured to texturize a casting surface for a continuous belt casting system according to embodiments of the disclosure.

FIGS. 9A-B illustrate a portion of a casting belt with a texturized belt surface according to embodiments.

FIGS. 10A-B illustrate a portion of a casting belt with a texturized belt surface according to embodiments.

FIG. 11 illustrates a portion of a casting belt with a texturized belt surface according to embodiments.

FIGS. 12A-B illustrate examples of surface topographies of as-cast metal slabs according to embodiments.

FIGS. 13A-B are scanning electron microscope images of a portion of an as-cast metal slab according to embodiments compared to a traditional as-cast metal slab.

FIGS. 14A-B are photographs illustrating porosity of a portion of an as-cast metal slab according to embodiments compared to a traditional as-cast metal slab.

FIGS. 15A-B are photographs illustrating grain structures of a portion of an as-cast metal slab according to embodiments compared to a traditional as-cast metal slab.

DETAILED DESCRIPTION

Described herein are systems and methods for texturizing a casting surface of a continuous belt casting system as well as continuous belt casting systems and methods that include texturized casting surfaces. Also described are cast products with a texturized surface. The systems and methods described herein may be utilized to texturize casting surfaces on various types of belt casting systems that include at least one endless metal belt having a belt surface that forms a casting surface. In some examples, the systems and methods may be utilized to texturize casting surfaces of a twin belt casting system.

Texturizing the casting surface may include providing the endless metal belt, optionally before the endless metal belt is installed within the belt casting system, and applying a predetermined texture to a first region of the endless metal belt without applying the predetermined texture to a second region of the endless metal belt. Stated differently, the method includes applying a texturizing force or technique to discrete regions of the casting surface such that the discrete regions are texturized to have a desired texture. The predetermined texture may be a non-randomized pattern of features (such as but not limited to a non-random pattern of grooves or ridges). Compared to the existing techniques of shot blasting or linishing that are applied to the entire casting surface, the methods described herein provide improved control over surface features of the texture (e.g., depth, diameter, shape, size, etc.) as well as the overall distribution of textures on the casting surface. As non-limiting examples, the systems and methods described herein may produce metal slabs in which surface and subsurface defects (e.g., exudates, open dendritic structures, meniscus marks, porosity, cracks, shrinkage marks, etc.) are minimized to acceptable levels and/or eliminated.

The improved control in tum provides an improved casting surface that minimizes metallurgical and mechanical surface defects such as exudates, intermetallics, ripples, etc., while minimizing structural anisotropy of the as-cast metal product formed by the casting surface compared to shot-blasted or linished surfaces. For example, the casting surface with the texture provided by the methods described herein may provide improved control of the heat flux from the molten metal and improved stabilization of contact points between the molten metal and the casting surface, which may reduce or eliminate casting defects in the as-cast metal product and may also eliminate or reduce thermal distortion on the endless belt. Various other benefits and advantages may be realized with the devices and methods provided herein, and the aforementioned advantages should not be considered limiting.

FIG. 1 illustrates an example of a continuous belt casting system 100. The particular arrangement or components illustrated in FIG. 1 should not be considered limiting. The continuous belt casting system 100 generally includes a molten metal source 102 and endless casting belts 104A-B. The endless casting belts 104A-B each have a casting surface 106 that at least partially form a casting cavity 108. Although not shown, an edge dam is provided at each side of the system so as to complete the enclosure of the casting cavity 108 at its edges. The endless casting belts 104A-B are rotated (represented by arrows 111) and molten metal 112 is introduced from the molten metal source 102 at an entrance 116 of the casting cavity 108 and advances through the casting cavity 108 via the endless casting belts 104A-B in a casting direction 110. The endless casting belts 104A-B may be arranged substantially parallel, although they need not be parallel in other examples. In some examples, the endless casting belts 104A-B may converge towards an exit 114 of the casting cavity 108. In various cases, the endless casting belts 104A-B are run at substantially the same speed such that the casting cavity 108 forms a moving mold that is static relative to the metal as the metal passes through the casting cavity 108. As the metal advances through the casting cavity 108, heat from the metal is transferred through the belts, and the molten metal becomes progressively solidified. The molten metal may be fully solidified before it reaches the exit 114 and may emerge from the exit 114 as a continuous, solid cast metal substrate 118.

The endless casting belts 104A-B may be supported on pulleys or other suitable support structures and may be driven by various suitable driving mechanisms. The support structures and driving mechanisms have been omitted from FIG. 1 for simplicity. The casting belts 104A-B may be constructed from various suitable materials, and in some cases may be constructed from suitable metals that may be sufficiently tensioned. In some examples, the casting belts 104A-B may be constructed from steel, iron, iron alloys, copper, copper alloys, aluminum, aluminum alloys, and/or various other suitable metal or non-metal material for belt casting. In various aspects, at least one of the casting surfaces 106, and in some cases both casting surfaces 106, are provided with a texture on the casting surface 106. The texture may control the heat flux from the molten metal and may stabilize the points of contact between the molten metal and the casting belts, which may minimize metallurgical and mechanical surface defects while minimizing structural anisotropy. The texture on the casting surface(s) 106 may also improve the usable life of the casting belt because the texture may minimize or eliminate thermal distortion on the casting belt.

FIG. 2 generally illustrates a method 200 of texturizing the casting surface of at least one casting belt for the belt casting system. For example, the endless casting belts 104A-B of the continuous belt casting system 100 may be texturized by the method 200. In various aspects, the method 200 is performed before the installation of the casting belt with the belt casting system, although it need not be in other examples.

In a block 202, and referring to FIG. 3, the method 200 includes receiving an endless casting belt 304. The endless casting belt 304 is substantially similar to the endless casting belts 104A-B and includes the elongated belt surface 106. In certain optional examples, the method 200 may receive the endless casting belt 304 after the formation of the endless casting belt 304 through various forming techniques. Techniques for forming the endless casting belt 304 may include, but are not limited to, laser welding or other suitable joining techniques.

As illustrated in FIG. 3, in various cases, across a width of the casting surface 106, the casting surface 106 may include at least one first region 320 that is configured to receive the texture and at least one second region 322 that is configured not to receive the texture. First regions 320 and/or second regions 322 may also be provided along the length of the casting surface 106 but have been omitted from FIG. 3 for simplicity. In cases with a plurality of first regions 320, the second region 322 may be provided between adjacent first regions 320. The number of first regions 320 and second regions 322 and arrangement of such regions on the casting surface should not be considered limiting. Moreover, the relative regions 320, 322 illustrated in FIG. 3 are exaggerated for the sake of illustration and are not intended to infer any particular size, distribution, pattern, or area of a region that receives the texture. For example, and as discussed in greater detail below, the regions 320, 322 may have surface features that are provided in the scale of micrometers or millimeters.

In a block 204, the method 200 includes texturizing the first region (or regions) 320 such that the first region 320 has a predetermined texture and the second region (or regions) 322) does not include the predetermined texture. In various aspects, the predetermined texture may be based on the type of metal being cast, and the predetermined texture for one type of metal may be the same as or different from the predetermined texture for another type of metal. As a non-limiting example, the predetermined texture for 5xxx series aluminum alloys, 6xxx series aluminum alloys, and 7xxx series aluminum alloys may be different from the predetermined texture for 1xxx series aluminum alloys and 3xxx series aluminum alloys, 8xxx series aluminum alloys, or any castable aluminum alloy, although it need not be in other examples. For an understanding of the number designation system most commonly used in naming and identifying aluminum and its alloys, such as AA numbers and other related designations such as “series” or “7xxx,” see “International Alloy Designations and Chemical Composition Limits for Wrought Aluminum and Wrought Aluminum Alloys” or “Registration Record of Aluminum Association Alloy Designations and Chemical Compositions Limits for Aluminum Alloys in the Form of Castings and Ingot,” both published by The Aluminum Association.

In some cases, the predetermined texture is based on a desired surface quality of the metal being cast. In various cases, the predetermined texture is based on a desired solidification rate of the metal during continuous casting. The predetermined texture may include, but is not limited to, a predetermined depth, a predetermined diameter or other dimension, a predetermined shape, and/or a predetermined pattern or distribution of the texture on the casting surface 106. In certain embodiments, the predetermined texture is a non-random texture pattern. In some embodiments, and as previously mentioned, the texture may be based on the type of metal being cast. As a non-limiting example, the texture used for a 5xxx series aluminum alloy (e.g., a cross-hatch texture) may be different from the texture used for a 6xxx series aluminum alloy (e.g., a ridge texture)

In one non-limiting example, the predetermined texture includes a depth of from 20 μm to 1000 μm, such as from 200 μm to 250 μm. In one optional example, the depth may be from 20 μm to 25 μm. In another non-limiting example, the predetermined texture includes a pattern or distribution of first regions 320 such that a distance between adjacent first regions 320 (or conversely a dimension of the intervening second region 322) is from 0.01 mm to 1.0 mm, such as from 0.1 mm to 0.3 mm.

As a further non-limiting example, the predetermined texture includes providing the texture as patterns such as but not limited to grooves, ridges, diamonds, etc. In one non-limiting example, the pattern may be grooves in each of the first regions 320 that extend along the length and/or the width of the casting surface 106. In such an example, the grooves may be parallel to the casting direction 110 or may extend at non-parallel angles relative to the casting direction 110. As one example, the grooves may be diagonal grooves. Other patterns of textures include, but are not limited to: ridges extending parallel, perpendicular, and/or at an oblique angle relative to the casting direction; grooves extending parallel, perpendicular, and/or at an oblique angle relative to the casting direction; and cross-hatching formed by a first set of grooves and a second set of grooves, where the first set of grooves are parallel, perpendicular, and/or at an oblique angle relative to the casting direction and the second set of grooves are parallel, perpendicular, and/or at an oblique angle relative to the casting direction. In one non-limiting example, the pattern may be cross-hatching, and both the first set of grooves and the second set of grooves are at oblique angles relative to the casting direction (e.g., 45° or any other angle) such that the cross-hatching forms a diamond pattern. Other patterns may be utilized as desired.

As another non-limiting example, the predetermined texture includes a crater having a particular geometrical or non-geometrical shape. In such examples, the shape may include, but is not limited to, a triangular shape, a square shape, an angled shape, a concave shape, or other suitable shape as desired. FIGS. 4A-C, SA-C, 6A-B, 7A-B, and 8A-C illustrate non-limiting examples of various techniques and/or devices that may be utilized in block 202 and are discussed in greater detail below.

Referring back to FIG. 2, in a block 204, the method may include installing the texturized casting belt 304 in the belt casting system. Installing the texturized endless casting belt 304 may include, but is not limited to, supporting the casting belt 304 on pulleys or other suitable supports and such that the casting surface 106 at least partially defines the casting cavity 108.

FIGS. 4A-C illustrate an example of texturizing the casting surface 106 that may be utilized in block 202. Referring to FIG. 4A, the method may include applying a masking agent 424 on the second regions 322 of the casting surface 106 such that the masking agent 424 is on the second regions 322 but not on the first region 320. In some cases, the masking agent 424 may be a chemical-resistant masking agent, although various suitable types of masking agents may be utilized. In various aspects, the masking agent 424 may be a polymeric masking agent, a ceramic masking agent, and/or a composite masking agent. In certain examples, applying the masking agent 424 of the second regions 322 may include, but is not limited to, rolling the masking agent 424 on the second regions 322, spraying the masking agent 424 on the second regions 322, painting the masking agent 424 on the second regions 322, ink-jet printing the masking agent 424 on the second regions 322, or various other suitable application techniques as desired.

Referring to FIG. 4B, after the masking agent 424 is applied, the first region(s) 320 (which is exposed because it does not include the masking agent 424) may be etched by applying an etchant 426 on the first region(s) 320 to provide the predetermined texture on the first region(s) 320. The etchant 426 may be various suitable types of etchants including, but not limited to, chemical etchants, electrochemical etchants, gas etchants, and/or liquid etchants. As some non-limiting examples, the etchant 426 may include picral, nital, ferric chloride, ammonium hydroxide, hydrogen peroxide, mixtures thereof, or other suitable etchants or combinations of etchants as desired. In various examples, applying the etchant 426 may include controlling at least one of an etching duration, etching temperature, etch rate, or other suitable etching details such that the first region(s) 320 is provided with the predetermined texture. In FIG. 4C, after etching is complete, the predetermined texture 428 is provided on the first region(s) 320 but not the second regions 322. The casting surface 106 may be rinsed, dried, and/or otherwise prepared prior to using the casting belt 304 with the belt casting system.

FIGS. 5A-C illustrate another example of texturizing the casting surface 106 that may be utilized in block 202 of the method 200. Referring to FIG. SA, the method may include applying the masking agent 424 to both the first region(s) 320 and the second regions 322 with the masking agent 424. In some cases, applying the masking agent 424 may include applying the masking agent 424 on the entire surface area of the casting surface 106. The method may include applying a laser 530 (e.g., from a laser head 532) onto the first region(s) 320 to laser texturize the first region(s) 320 and remove the masking agent 424 from the first region(s) 320 to expose the casting surface 106 in the first region(s) 320. The laser head 532 illustrated should not be considered limiting. In various aspects, applying the laser 530 may include controlling a laser control feature while applying the laser 530. The laser control feature may include, but is not limited to, an application mode of the laser (e.g., pulsing, continuous, etc.), a number of passes of the laser 530 over the first region(s) 320, a speed of the movement of the laser head 532 relative to the first region(s) 320, a laser energy level, a pulse duration, an angle of incidence of the laser relative to the casting surface 106, combinations thereof, or other suitable laser control features.

As illustrated in FIG. SB, similar to FIG. 4B, after applying the laser 530, the method may include applying the etchant 426 to the first region(s) 320 to provide the predetermined texture. As illustrated in FIG. 5C, and similar to FIG. 4C, after etching is complete, the predetermined texture 428 is provided on the first region(s) 320 but not the second regions 322. The casting surface 106 may be rinsed, dried, and/or otherwise prepared prior to using the casting belt 304 with the belt casting system.

FIGS. 6A-B illustrate another example of texturizing the casting surface 106 that may be utilized in block 202 of the method 200. As illustrated in FIG. 6A, the method includes applying a laser 630 (e.g., from a laser head 632) to the first region(s) 320 but not the second regions 322. The laser 630 and/or the laser head 632 may be the same as or different from the laser 530 and/or the laser head 532. In certain aspects, applying the laser 630 may include moving the laser head 632 relative to the casting surface 106, moving the casting surface 106 relative to the laser head 632, or moving both the laser head 632 and the casting surface 106. In various aspects, applying the laser 630 may include controlling a laser control feature such that the predetermined texture 428 is provided on the first region(s) 320. The laser control feature may include, but is not limited to, an application mode (e.g., pulsing, continuous, etc.), a number of passes of the laser 630 over the first region 320, a speed of the movement of the laser head 632 relative to the first region 320, a laser energy level, a pulse duration, an angle of incidence of the laser relative to the casting surface 106, combinations thereof, or other suitable laser control features. As one non-limiting example, applying the laser 630 may include applying the laser 630 in a pulsing mode. As another non-limiting example, applying the laser 630 may include applying the laser 630 on the first region(s) 320 in one pass or in more than one pass.

As illustrated in FIG. 6B, after applying the laser 630, the predetermined texture 428 is provided on the first region(s) 320 but not the second regions 322. Optionally, after applying the laser 630, an etchant (such as the etchant 426) may be applied to the first region(s) 320 to further texturize the first region(s) 320 such that the first region(s) 322 has the predetermined texture or another predetermined texture.

FIGS. 7A-B illustrate another example of texturizing the casting surface 106 that may be utilized in block 202 of the method 200. The method illustrated in FIGS. 7A-B is substantially similar to the method illustrated in FIGS. 6A-B except that the method includes applying a coupling layer 734 on the casting surface 106 prior to applying the laser 630. Applying the coupling layer 734 may include applying the coupling layer 734 on both the first region(s) 320 and the second regions 322 or on just the first region(s) 320. The coupling layer 734 may be various suitable materials that improve coupling between the laser and the casting surface 106 to improve the morphology of the predetermined texture 428. In one non-limiting example, the coupling layer 734 is a water layer.

FIGS. SA-C illustrate an example of a texturing tool 836 that may be utilized to mechanically texturize the casting surface 106 in block 202 of the method 200. In some non-limiting examples, the texturizing tool 836 may induce grooves on the casting surface 106 along the direction of movement as the predetermined texture. Referring to FIG. 8A, the texturing tool 836 may include a holder 838 and a roller 840 that is rotatably supported on the holder 838. As best illustrated in FIGS. 8B-C, which show a portion of the roller 840 in greater detail, the roller 840 has a roller surface 842, and the roller surface 842 includes one or more ribs 844. In the example of FIGS. 8A-C, the roller surface 842 includes a plurality of ribs 844, and each rib 844 is configured to engage a corresponding first region 320 such that a plurality of first regions 320 are provided with the predetermined texture. In this example, the portions of the roller surface 842 without the ribs 844 are configured to contact corresponding second regions 322 of the casting surface 106 such that the predetermined texture is not provided on the second region 322 while the first regions 320 are texturized. The number, shape, profile, or size of the ribs 844 should not be considered limiting and such features may be controlled as desired such that the texturizing tool 836 provides the predetermined texture on the first region 320. As some non-limiting examples, referring to FIG. 8C, a height 846 of one or more ribs 844, a maximum distance 848 between adjacent ribs 844, and/or a minimum distance 850 between adjacent ribs 844 may be controlled such that the texturizing tool 836 provides the predetermined texture.

During a texturizing process with the texturizing tool 836, the roller 840 is contacted with the casting surface 106 and such that the at least one rib 844 contacts the first region 320 of the casting surface 106. The method may include contacting the roller 840 with the casting surface 106 such that a portion of the roller surface 842 without the at least one rib 844 contacts the second region 322. The method includes moving the roller 840 along the casting surface 106 such that the at least one rib 844 forms the predetermined texture on the first region 320 but not on the second region 322. In some examples, the method may include controlling an application force while moving the roller 840 along the casting surface 106.

Various other suitable techniques may be utilized for applying a predetermined texture to the first region 320 of the casting surface 106 and such that the second region 322 does not include the predetermined texture.

FIGS. 9A-B illustrate a portion of a casting belt 904 substantially similar to the casting belts 104. As illustrated in FIGS. 9A-B, the casting belt 904 includes a belt surface 952 that is texturized with a texture pattern 954. In the embodiment illustrated, the texture pattern 954 is a cross-hatching pattern formed by first grooves 956 extending in a first direction and second grooves 958 extending in a second direction and intersecting the first grooves 956. Optionally, the first direction or the second direction may be a casting direction, although it need not be in other embodiments. As an example, the first direction and the second direction may both be at an oblique angle relative to the casting direction such that the cross-hatching pattern is a diamond pattern in the casting direction.

FIGS. 10A-B illustrate a portion of a casting belt 1004 that is substantially similar to the casting belts 104 and 904, and includes the belt surface 952 that is texturized with a texture pattern 1054. The texture pattern 1054 is similar to the texture pattern 954 and is a cross-hatching pattern, however, compared to the texture pattern 954, the spacing between adjacent first grooves 956 and between adjacent second grooves 958 is increased in the texture pattern 1054.

FIG. 11 illustrates a portion of a casting belt 1104 that is substantially similar to the casting belts 104, 904, and 1004, and includes the belt surface that is texturized with a texture pattern 1154. Compared to the texture patterns 954, 1054, the texture pattern 1154 is a ridge pattern formed by parallel grooves 1156. The grooves 1156 may extend in the casting direction, in a direction perpendicular to the casting direction, and/or in a direction that is at an oblique angle relative to the casting direction.

The casting belts 104, 904, 1004, and 1104 are for illustrative purposes only and should not be considered limiting on the disclosure. As mentioned, in other embodiments, other textures and/or texture patterns may be provided on a belt surface of a casting belt as desired.

Referring back to FIG. 1, a method of forming a metal slab with a texturized slab surface may include providing the casting belts 104A-B such that at least one of the casting belts 104A-B includes a texturized belt surface. Optionally, both casting belts 104A-B may be provided with texturized belt surfaces. The method includes introducing the molten metal 112 into the casting cavity 108 and advancing the metal 112 through the casting cavity 108 via the casting belts 104A-B such that heat from the metal 112 is transferred through the belts, and the molten metal 112 becomes progressively solidified. The molten metal 112 may be fully solidified before it reaches the exit 114 and may emerge from the exit 114 as a continuous, solid cast metal slab. One or both slab surfaces of the cast metal slab may include the texture from the casting belts 104A-B.

FIGS. 12A-B illustrate non-limiting examples of as-cast metal slabs according to embodiments. As illustrated in both FIGS. 12A-B, the pattern of the casting belts generally corresponds to texture patterns on the surfaces of the as-cast slabs. As used herein, the surface texture on the metal slab generally corresponds to the texturized pattern of the casting belts in that the surface texture on the metal slab may have the same shape and/or patterns, but the dimensions (e.g., depth, height, etc.) need not necessarily be the same. As an example, during casting, the molten metal may penetrate only a fraction of the depth of the grooves and/or other portion of the texturized pattern, and thus the surface texture on the metal slab will generally correspond to the texturized pattern of the casting belts because of such partial penetration.

FIG. 12A illustrates the surface topography of an as-cast metal slab 1260A formed using a casting belt having a ridged texture pattern. As illustrated in FIG. 12A, the slab 1260A formed with the ridged texture pattern had a relatively uniform cast surface. FIG. 12B illustrates the surface topography of an as-cast metal slab 1260B formed using a casting belt having a cross-batch texture pattern, and the slab 1260B had a relatively uniform cast surface.

As previously mentioned, metal slabs according formed with the texturized belt surfaces described herein may have improved surface characteristics, sub-surface characteristics, and performance compared to metal slabs formed using traditional techniques. As non-limiting examples, compared to traditionally cast metal slabs, metal slabs formed using the systems and methods described herein may have minimized or eliminated exudates, homogeneously or more evenly distributed intermetallics, minimized or eliminated voids, minimized or eliminated cracks, minimized or eliminated open dendritic structures, minimized or eliminated meniscus marks, etc., while maintaining internal quality and performance. The metal slabs with improved surface and sub-surface characteristics described herein may in turn have improved performance and/or uses. As a non-limiting example, the metal slabs descried herein may have improved bond durability compared to traditional metal slabs.

FIGS. 13A-B, 14A-B, and 15A-B illustrate a non-limiting example comparing a metal slab 1360 formed with a texturized casting belt and a metal slab 1361 formed using a traditional technique. The casting parameters for the slabs 1360, 1361 was the same except for the casting belts—the metal slab 1360 was formed with a casting belt having a cross-hatch texture on the belt surface, and the metal slab 1361 was formed with a traditional casting belt having a smooth surface.

FIGS. 13A-B are scanning electron microscope photographs of portions of the metal slabs 1360, 1361. As illustrated in FIG. 13A, the surface of the metal slab 1360 was generally free from exudates, while as illustrated in FIG. 13B, the surface of the metal slab 1361 included exudates.

FIGS. 14A-B illustrate porosity of portions of the metal slabs 1360, 1361. As illustrated by comparing FIG. 14A with FIG. 14B, the porosity of the metal slab 1360 was minimal and uniform subsurface porosity, while the metal slab 1361 had relatively increased porosity that was less uniform.

FIGS. 15A-B illustrate grain structures of portions of the metal slabs 1360, 1361. As illustrated in these figures, the grain structure of the metal slabs 1360, 1361 was generally the same.

Overall, 13A-B, 14A-B, and ISA-B illustrate how the metal slabs 1360 described herein have improved surface characteristics compared to traditional slabs 1361 while maintaining internal characteristics and performance of the slabs.

A collection of exemplary embodiments are provided below, including at least some explicitly enumerated as “Illustrations” providing additional description of a variety of example embodiments in accordance with the concepts described herein. These illustrations are not meant to be mutually exclusive, exhaustive, or restrictive; and the disclosure not limited to these example illustrations but rather encompasses all possible modifications and variations within the scope of the issued claims and their equivalents.

Illustration 1. A method of texturizing a casting mold of a continuous belt casting system, the method comprising: providing at least one endless belt comprising an elongated belt surface, wherein the elongated belt surface comprises at least a first region and at least a second region adjacent to the first region across a width of the elongated belt surface, and wherein the elongated belt surface is configured to at least partially define a casting cavity of the continuous belt casting system; and texturizing the elongated belt surface by applying a predetermined texture to the first region and such that the second region does not comprise the predetermined texture.

Illustration 2. The method of any preceding or subsequent illustrations or combination of illustrations, wherein providing the at least one endless belt comprises providing at least one of a copper-based endless belt, an iron-based endless belt, an aluminum-based endless belt, a steel-based endless belt, or any other suitable texturable belts as desired.

Illustration 3. The method of any preceding or subsequent illustrations or combination of illustrations, wherein the at least one endless belt is a first endless belt and the elongated belt surface is a first elongated belt surface, and wherein the method comprises: providing a second endless metal belt comprising a second elongated belt surface, wherein the second elongated belt surface is configured to at least partially define the casting cavity, and wherein the second elongated belt surface comprises a first region and a second region; and texturizing the second elongated belt surface by applying the predetermined texture to the first region of the second elongated belt surface and such that the second region of the second elongated belt surface does not comprise the predetermined texture.

Illustration 4. The method of any preceding or subsequent illustrations or combination of illustrations, wherein texturizing the elongated belt surface comprises: applying a masking agent on at least the second region of the elongated belt surface; etching the first region of the elongated belt surface with an etchant to form the predetermined texture; and removing the masking agent from the second region of the elongated belt surface.

Illustration 5. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the masking agent comprises applying a chemical-resistant masking agent.

Illustration 6. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the masking agent comprises only applying the masking agent on the second region and such that the masking agent is not applied to the first region, and wherein etching the first region comprises etching the first region without the masking agent. In some embodiments, the etching or texture may be provided on both sides of the belt. In certain embodiments, an etching or texture provided on one side of the belt (e.g., a water side of the belt during casting) and may be different from an etching or texture provided on another side of the bel (e.g., a molten metal side of the belt during casting).

Illustration 7. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the masking agent comprises: applying a masking agent on both the first region and on the second region of the elongated belt surface; and laser texturing the first region of the elongated belt surface such that the masking agent is removed from the first region, and wherein etching the first region comprises etching the first region without the masking agent. In various embodiments, the etching or texture may be provided on both sides of the belt. In certain embodiments, an etching or texture provided on one side of the belt (e.g., a water side of the belt during casting) and may be different from an etching or texture provided on another side of the bel (e.g., a molten metal side of the belt during casting).

Illustration 8. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the masking agent comprises applying the masking agent by at least one of rolling, spraying, painting, or ink-jet printing.

Illustration 9. The method of any preceding or subsequent illustrations or combination of illustrations, wherein etching comprises applying at least one of a chemical etchant, a liquid etchant, or a gas etchant.

Illustration 10. The method of any preceding or subsequent illustrations or combination of illustrations, wherein etching comprises controlling at least one of an etching duration or an etching temperature to form the predetermined texture.

Illustration 11. The method of any preceding or subsequent illustrations or combination of illustrations, wherein texturizing the elongated belt surface comprises laser texturing the first region of the elongated belt surface.

Illustration 12. The method of any preceding or subsequent illustrations or combination of illustrations, wherein laser texturing comprises moving a laser relative to the elongated belt surface or moving the elongated belt surface relative to the laser.

Illustration 13. The method of any preceding or subsequent illustrations or combination of illustrations, wherein laser texturing comprises controlling at least one of a laser mode, a speed of a laser head relative to the elongated belt surface, a laser energy level, a laser pulse duration, an angle of incidence of the laser relative to a plane of the elongated belt surface, or a number of passes of the laser over the first region of the elongated belt surface.

Illustration 14. The method of any preceding or subsequent illustrations or combination of illustrations, wherein laser texturing comprises applying a water layer on at least the first region of the elongated belt surface and laser texturing the first region with the water layer.

Illustration 15. The method of any preceding or subsequent illustrations or combination of illustrations, further comprising etching the first region of the elongated belt surface after laser texturing.

Illustration 16. The method of any preceding or subsequent illustrations or combination of illustrations, wherein texturing comprises mechanical texturing, and wherein mechanical texturing comprises: providing a texturing tool comprising a roller, wherein the roller comprises a roller surface, and wherein the roller surface comprises at least one rib; contacting the roller with the elongated belt surface and such that the at least one rib contacts the first region of the elongated belt surface; and moving the roller along the elongated belt surface such that the at least one rib forms the predetermined texture on only the first region of the elongated belt surface.

Illustration 17. The method of any preceding or subsequent illustrations of combination of illustrations, wherein mechanical texturing further comprises controlling an application force while moving the roller along the elongated belt surface.

Illustration 18. The method of any preceding or subsequent illustrations or combination of illustrations, wherein the elongated belt surface comprises a plurality of first regions, wherein the second region is between adjacent first regions across the width of the elongated belt surface, and wherein the method further comprises: texturizing the elongated belt surface by applying the predetermined texture to the plurality of first regions.

Illustration 19. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the predetermined texture to the plurality of first regions comprises applying the predetermined texture such that a distance between adjacent first regions, which is a dimension of the second region, is from 0.01 mm to 1.0 mm.

Illustration 20. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the predetermined texture to the plurality of first regions comprises applying the predetermined texture such that a distance between adjacent first regions is from 0.1 mm to 0.3 mm.

Illustration 21. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the predetermined texture to the first region comprises forming a crater having a depth from 20 μm to 1000 μm.

Illustration 22. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the predetermined texture to the first region comprises forming the crater having the depth from 200 μm to 250 μm.

Illustration 23. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the predetermined texture to the first region comprises forming the crater that is elongated in a casting direction as a groove.

Illustration 24. The method of any preceding or subsequent illustrations or combination of illustrations, further comprising installing the at least one endless belt such that the elongated belt surface at least partially forms the casting cavity.

Illustration 25. An endless metal belt for a continuous belt casting system comprising a casting surface prepared by the method of any preceding or subsequent illustrations or combination of illustrations.

Illustration 26. A method of texturizing a casting mold of a continuous belt casting system, the method comprising: providing at least one endless belt comprising an elongated belt surface, wherein the elongated belt surface comprises at least a first region and a second region across a width of the elongated belt surface, wherein the second region is adjacent to the first region, and wherein the elongated belt surface is configured to at least partially define a casting cavity of the continuous belt casting system; and locally texturizing the elongated belt surface such that the first region comprises a predetermined texture and the second region does not comprise the predetermined texture.

Illustration 27. A method of texturizing a casting mold of a continuous belt casting system, the method comprising: providing at least one endless belt comprising an elongated belt surface, wherein the elongated belt surface comprises a plurality of first regions and a plurality of second regions, wherein adjacent first regions of the plurality of first regions are separated by one of the plurality of second regions, and wherein the elongated belt surface is configured to at least partially define a casting cavity of the continuous belt casting system; and texturizing the elongated belt surface by applying a predetermined texture only to the plurality of first regions and such that a distance between adjacent first regions of the plurality of first regions is from 0.01 mm to 1.0 mm, or any suitable dimension.

Illustration 28. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the predetermined texture only to the plurality of first regions comprises applying the predetermined texture such that the distance between the adjacent first regions of the plurality of first regions is from 0.1 mm to 0.3 mm, or any suitable distance.

Illustration 29. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the predetermined texture only to the plurality of first regions comprises forming a crater having a depth from 20 μm to 1000 μm in each first region of the plurality of first regions, or any suitable depth.

Illustration 30. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the predetermined texture only to the plurality of first region comprises forming the crater having the depth from 200 μm to 250 μm in each first region of the plurality of first regions, or any suitable depth.

Illustration 31. The method of any preceding or subsequent illustrations or combination of illustrations, wherein applying the predetermined texture only to the plurality of first regions comprises forming a groove in each first region of the plurality of first regions that is elongated in a casting direction and comprises a depth from 20 μm to 1000 μm.

Illustration 32. A continuous belt casting system comprising an endless belt comprising an elongated belt surface, wherein the elongated belt surface comprises a predetermined texturized pattern defined in the elongated belt surface, wherein the elongated belt surface at least partially defines a casting cavity of the continuous belt casting system.

Illustration 33. The continuous belt casting system of any preceding or subsequent illustrations or combination of illustrations, wherein the predetermined texturized pattern comprises a ridge pattern, a groove pattern, a cross-hatch pattern, or a diamond pattern formed on the elongated belt surface.

Illustration 34. The continuous belt casting system of any preceding or subsequent illustrations or combination of illustrations, wherein the endless belt is a first endless belt and the elongated belt surface is a first elongated belt surface, and wherein the continuous belt casting system comprises a second endless belt comprising a second elongated belt surface at least partially defining the casting cavity, wherein the second elongated belt surface comprises a predetermined texturized pattern.

Illustration 35. The continuous belt casting system of any preceding or subsequent illustrations or combination of illustrations, wherein the predetermined texturized pattern of the second elongated belt surface is the same as the predetermined texturized pattern of the first elongated belt surface.

Illustration 36. A method of casting a metal slab, the method comprising: introducing molten metal into a casting cavity defined by two endless belts, wherein at least one of the endless belts comprises a belt surface comprising a predetermined texturized pattern; advancing the molten metal through the casting cavity by advancing the endless belts and such that the molten metal solidifies; and causing the solidified molten metal to emerge from an exit of the casting cavity as a metal slab and such that the as-cast metal slab comprises a surface texture pattern corresponding to the texturized pattern of the belt surface.

Illustration 37. The method of any preceding or subsequent illustrations or combination of illustrations, wherein the predetermined texturized pattern on the belt surface comprises a ridge pattern, a, groove pattern, a cross-hatch pattern, or a diamond pattern.

Illustration 38. The method of any preceding or subsequent illustrations or combination of illustrations, further comprising changing the predetermined texturized pattern from a first pattern to a second pattern based on a type of metal being cast.

Illustration 39. The as-cast metal slab formed by the method of any preceding or subsequent illustrations or combination of illustrations.

Illustration 40. An as-cast metal slab formed by a continuous belt caster, the as-cast metal slab comprising a slab surface, the slab surface comprising a surface texture pattern corresponding to a predetermined texturized pattern on a belt surface of an endless belt of the continuous belt caster.

Illustration 41. The as-cast metal slab of any preceding or subsequent illustrations or combination of illustrations, wherein the surface texture pattern comprises a groove pattern, a cross-hatching pattern, or a diamond pattern.

Illustration 42. A method of texturizing a casting mold of a continuous belt casting system, the method comprising: providing at least one endless belt comprising an elongated belt surface; and texturizing the elongated belt surface by applying a predetermined texture pattern to the elongated casting, the predetermined texture pattern comprising a repeatable pattern of grooves or ridges.

The subject matter of embodiments is described herein with specificity to meet statutory requirements, but this description is not necessarily intended to limit the scope of the claims. The claimed subject matter may be embodied in other ways, may include different elements or steps, and may be used in conjunction with other existing or future technologies. This description should not be interpreted as implying any particular order or arrangement among or between various steps or elements except when the order of individual steps or arrangement of elements is explicitly described. Directional references such as “up,” “down,” “top,” “bottom,” “left,” “right,” “front,” and “back,” among others, are intended to refer to the orientation as illustrated and described in the figure (or figures) to which the components and directions are referencing.

The above-described aspects are merely possible examples of implementations, merely set forth for a clear understanding of the principles of the present disclosure. Many variations and modifications may be made to the above-described embodiment(s) without departing substantially from the spirit and principles of the present disclosure. All such modifications and variations are intended to be included herein within the scope of the present disclosure, and all possible claims to individual aspects or combinations of elements or steps are intended to be supported by the present disclosure. Moreover, although specific terms are employed herein, as well as in the claims that follow, they are used only in a generic and descriptive sense, and not for the purposes of limiting the described embodiments, nor the claims that follow.

SYSTEMS AND METHODS FOR PRODUCING TEXTURIZED CASTING MOLDS OF A CONTINUOUS BELT CASTER

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