The subject matter herein generally relates to the field of metal alloys, and in particular to a Zirconium (Zr)-based amorphous alloy.
Amorphous alloys are widely used in many fields, such as aviation, spaceflight, IT electronics, mechanics, and chemical industry and so on. A general method for manufacturing an amorphous alloy is to cool a melted alloy quickly to be below a glass transformation temperature (Tg) at a certain cooling speed. The extremely fast cooling speed avoids crystal nucleation and growth, and finally accomplishes a completely amorphous structure. If the cooling speed required for turning a material into an amorphous structure is lower, it is easier to form a large-sized amorphous structure of the material. Generally, a critical diameter that can form a cast round bar of a completely amorphous structure is used as glass forming ability (GFA) of the alloy.
The Zr-based amorphous alloys that have been developed so far for forming an amorphous structure in the world centrally exist in the Zr-TM-Al or Zr-TM-Be (TM is Ti, Cu, Ni, or Co) system. With certain components of such alloys, a melt may cool down at a critical cooling speed of less than 10 degrees Kelvin (K)/second to form a bulk amorphous alloys of a thickness of a centimeter magnitude. Currently, the manufacturing of such alloys occurs primarily in labs with cooper molds. However, in industrial production, the amorphous alloy is manufactured through steel molds to save cost, and the thickness of such amorphous alloy is small.
Implementations of the present technology will now be described, by way of example only, with reference to the attached figures.
It will be appreciated that for simplicity and clarity of illustration, where appropriate, reference numerals have been repeated among the different figures to indicate corresponding or analogous elements. In addition, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein can be practiced without these specific details. In other instances, methods, procedures, and components have not been described in detail so as not to obscure the related relevant feature being described. Also, the description is not to be considered as limiting the scope of the embodiments described herein. The drawings are not necessarily to scale and the proportions of certain parts may be exaggerated to better illustrate details and features of the present disclosure.
Several definitions that apply throughout this disclosure will now be presented.
The term “substantially” is defined to be essentially conforming to the particular dimension, shape, or other feature that the term modifies, such that the component need not be exact. For example, “substantially cylindrical” means that the object resembles a cylinder, but can have one or more deviations from a true cylinder. The term “comprising,” when utilized, means “including, but not necessarily limited to”; it specifically indicates open-ended inclusion or membership in the so-described combination, group, series and the like.
A Zr-based amorphous alloy can be represented by the following formula: ZraCubAlcNidTieMf. a, b, c, d, e, and f of the formula can be corresponding atomic percents with 50≦a≦55, 25≦b≦30, 15≦c≦24, 0.1≦d≦9, 0.1≦e≦5, 0.1≦f≦5, and a+b+c+d+e+f≦100. M can be selected from one or more of the following group consisting of Sc, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, and mixtures thereof.
A method can be configured for manufacturing a Zr-based amorphous alloy. The method can include: preparing raw materials, wherein the raw materials can include Zr, Cu, Al, Ni, Ti, and M; melting the raw materials under a vacuum condition to achieve homogeneous fusion of all components; and casting the melted raw materials into a steel mold to cool down, so as to obtain the Zr-based amorphous alloy presented by the following formula ZraCubAlcNidTieMf. M can be selected from one or more of the following group consisting of Sc, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, and mixtures thereof. The elements in the raw materials have the following ratio: ZraCubAlcNidTieMf, wherein a, b, c, d, e, and f of the formula are corresponding atomic percents with 50≦a≦55, 25≦b≦30, 15≦c≦24, 0.1≦d≦9, 0.1≦e≦5, 0.1≦f≦5, and a+b+c+d+e+f≦100. The Zr-based amorphous alloy has a glass forming ability of 2.5 millimeters.
The present application provides an easily formable Zr-based amorphous alloy, where the Zr-based amorphous alloy of an amorphous structure may be subject to a steel mold casting method to generate amorphous bulk materials or parts of an amorphous structure. The Zr-based amorphous alloy can include Zr, Cu, Al, Ni, Ti, and one or more elements of rare earth. An atomic percent of each element in the final amorphous alloy can fulfill the following general formula: ZraCubAlcNidTieMf. a, b, c, d, e, and f can be corresponding atomic percent content of elements in the amorphous alloy, 50≦a≦55, 25≦b≦30, 15≦c≦24, 0.1≦d≦9, 0.1≦e≦5, 0.1≦f≦5, a+b+c+d+e+f≦100. M can be selected from one or more of the following group consisting of Sc, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, and mixtures thereof. In at least one embodiment, atomic percent content of elements in the amorphous alloy can have a preferable range, 50≦a≦53, 25≦b≦30, 15≦c≦20, 3≦d≦8, 0.1≦e≦2, 0.1≦f≦2, a+b+c+d+e+f≦100.
The present application provides a method for manufacturing a Zr-based amorphous alloy of the foregoing molecular formula. The method includes: preparing components in the foregoing ZraCubAlcNidTieMf Zr-based amorphous alloy according to a molecular ratio within a range of a, b, c, d, e, and f in the alloy, where 50≦a≦55, 25≦b≦30, 15≦c≦24, 0.1≦d≦9, 0.1≦e≦5, 0.1≦f≦5, a+b+c+d+e+f≦100; melting such components into a master alloy until they are fully blended homogeneously; and performing casting and cooling for the master alloy to obtain an amorphous ingot formed of the Zr-based amorphous alloy. For example, the Zr-based amorphous alloy in the present application can have one of the components listed in Table 1:
At block 101, raw materials are prepared. The raw materials can include Zr, Cu, Al, Ni, Ti, and M. M can be selected from one or more of the following group consisting of Sc, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, and mixtures thereof. The elements in the raw materials can have the following ratio: ZraCubAlcNidTieMf, a, b, c, d, e, and f of the formula are corresponding atomic percents with 50≦a≦55, 25≦b≦30, 15≦c≦24, 0.1≦d≦9, 0.1≦e≦5, 0.1≦f≦5, and a+b+c+d+e+f≦100. Raw materials can be prepared within the range of the formula at a specific atomic percent. For example, Raw materials can be prepared according to each component and a specific atomic percent in Table 1.
In the preparation process, components of the alloy can be prepared according to the components and atomic percentages in Table 1 by using materials such as metal rods, blocks, ingots and plates made of elements Zr, Cu, Al, Ni, Ti, Er, and the like, with a purity of 99.9%.
At block 102, the prepared raw materials are melted under a vacuum condition or protection atmosphere to achieve homogeneous fusion of all components.
At block 103, the melted raw materials are cast and cooled to form the amorphous alloy.
The melted alloy material can be cast into a steel mold to cool down, so as to obtain the Zr-based amorphous alloy of the foregoing molecular formula according to the corresponding components. The cooling speed of the cooling processing can be about 10 K/second, so as to suppress crystallization and form amorphous alloy ingots.
For describing properties of the Zr-based amorphous alloy of the example embodiment, the present application provides two groups of Zr-based amorphous alloy. The first group of Zr-based amorphous alloy can employ the Zr-based amorphous alloy of the example embodiment, and the formula of the first group of Zr-based amorphous alloy can be Zr51Cu26Al15.5Ni6Ti1Er0.5. The second group of Zr-based amorphous alloy can employ other Zr-based amorphous alloys of a comparative example which do not include any elements of rare earth, and the formula of the second group of Zr-based amorphous alloy can be Zr51Cu26Al16Ni6Ti1.
Two groups of Zr-based amorphous alloy can be manufactured by the foregoing method to form the amorphous ingots. The amorphous ingots can then be melted into a graphite crucible of a vacuum die casting machine (not shown), and then the melted amorphous ingots can be cast into a steel mold to form a number of samples. In at least one embodiment, the melted amorphous ingots can be cast to form an amorphous alloy plate. The plate can be step-shaped, and can be cut into six samples with a length of 100 millimeters and a width of 10 millimeters. Thicknesses of the six plates can be 3.0 millimeters, 2.5 millimeters, 2.0 millimeters, 1.5 millimeters, 1.0 millimeters, 0.5 millimeters. In at least one embodiment, the amorphous ingots can be directly cast to form each sample with a specific size.
Each group of Zr-based amorphous alloy can be cut into six samples. The first group of Zr-based amorphous alloy is labeled as samples 1 to 6, each having a length of 100 millimeters and a width of 10 millimeters. Samples 1 to 6 respectively have a thickness of 3.0 millimeters, 2.5 millimeters, 2.0 millimeters, 1.5 millimeters, 1.0 millimeters, 0.5 millimeters. The second group of Zr-based amorphous alloy is labeled as samples 7 to 12, each having a length of 100 millimeters and a width of 10 millimeters. Samples 7 to 12 respectively have a thickness of 3.0 millimeters, 2.5 millimeters, 2.0 millimeters, 1.5 millimeters, 1.0 millimeters, 0.5 millimeters. Samples 1-12 were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), hardness measurements, and strength measurements.
Samples 1 and 7 were investigated by SEM which is performed with a JSM-6510 scanning electron microscope, using an accelerating voltage of 20 kilovolt (kV).
Samples 1, 2, 4, and 8-10 were investigated by XRD which is performed with an Empyrean x-ray diffractometer, using a Ka x-ray source, an accelerating voltage of 40 (kV), an electric current of 20 milliampere (mA), a step scan with a scanning step-length of 0.0167 degrees, scanning angle of about 20 to 80 degrees, and a scanning speed of about 25 degrees/minute.
Samples 1 and 7 were investigated by DSC which is performed with a NetzschSTA449F3 differential scanning calorimeter, using a heat rate of about 20 K/min, and a scanning area from 50 to 920 degrees, to obtain the glass transition temperatures Tg, the crystallization temperatures Tx, and the melting temperatures Tm. Table 2 gives the characteristic values extracted from the DSC thermogram of
Table 2 shows that an under cooled liquid region of sample 1 can be greater than the under cooled liquid region of sample 7. As thus, the Zr-based amorphous alloy of the present application which is obtained by adding rare earth elements can have a larger under cooled liquid region, to improve the stability of amorphous phase.
Table 3 shows the Vickers hardness HV of the completely amorphous structures of samples 6 and 12 that was measured with a HM-100 Vickers hardness testing machine, using a load of 9.8 N, a load time of 10 seconds, and a stabilization time of 5 seconds. The hardness of sample 6 can be greater than that of sample 12. As thus, the hardness of the Zr-based amorphous alloy can be improved by adding rare earth elements.
Table 4 shows the yield strengths of samples 1-5 and 8-12 that was measured with Zwick/Roell universal testing machine, using a maximum load of 10 KN, and a span length of 40 millimeters. The yield strengths of samples 9-11 can be substantially the same, and the yield strength of sample 8 can be much less than that of sample 9. As thus, the Zr-based amorphous alloy of sample 9 which is not added with rare earth elements can have crystal phase structures. The yield strengths of samples 1-5 can be substantially the same. As thus, the Zr-based amorphous alloy of sample 1 which is added with rare earth elements cannot have crystal phase structures. The yield strength of the Zr-base amorphous alloy of the present application can be substantially 2125 MPa.
While the present disclosure has been described with reference to particular embodiments, the description is illustrative of the disclosure and is not to be construed as limiting the disclosure. Therefore, those of ordinary skill in the art can make various modifications to the embodiments without departing from the scope of the disclosure, as defined by the appended claims.
Number | Date | Country | Kind |
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201510252553.0 | May 2015 | CN | national |