Patent Application
20210016342
The present disclosure relates to object-processing method and device.
Priority is claimed on Japanese Patent Application No. 2018-049818, filed Mar. 16, 2018, the content of which is incorporated herein by reference.
When molding an object made of metal through forging as a type of plastic working method, as is well known, the object deforms and generates heat due to the action of an external force. This heat generation of the object may cause a change (transformation) of the structure (for example, crystal structure) of the object and may deteriorate the mechanical properties of the object.
For example, Patent Document 1 shown below discloses a method of manufacturing a forged member, in which a blank (object) made of steel is cooled (rapidly cooled) while an external force is applied to the blank during the forging. That is, in this manufacturing method, at the same time as the blank is pressed with a mold to be forged into a predetermined shape, the blank is rapidly cooled by a cooling means provided in the mold, and forging, quenching and tempering of the blank are simultaneously performed.
[Patent Document 1] Japanese Unexamined Patent Application, First Publication No. 2015-188927
In the above conventional technique, since the blank (object) is cooled from the outside using the cooling means provided in the mold, it is difficult to cool the inside of the object to the same degree as the outer portion thereof due to the heat capacity of the object. This becomes further remarkable as the thickness (heat capacity) of the object increases. Therefore, in the conventional technique, it is difficult to maintain the inside structure of the object in the same degree as that of the outer portion.
The present disclosure is made in view of the above circumstances, and an object thereof is to further limit the structural change and deformation of an object compared with the conventional technique or to more appropriately cool the object.
In order to obtain the above object, an object-processing method of a first aspect of the present disclosure includes: applying a specific process to an object to be processed by connecting a power source to the object to be processed.
In the first aspect of the present disclosure, the specific process may be a cooling process on the object to be processed.
In the first aspect of the present disclosure, the specific process may be a transformation-limiting process on a structure of the object to be processed.
In the first aspect of the present disclosure, the power source may cause free electrons in the object to be processed to be emitted to the outside by being connected to the object to be processed.
In the first aspect of the present disclosure, the power source may collect the free electrons emitted to the outside from the object to be processed.
In the first aspect of the present disclosure, at the time the power source is connected to the object to be processed, no other power source that supplies an electric current to the object to be processed has to be connected to the object to be processed.
In the first aspect of the present disclosure, the object to be processed may be a metal body that generates heat by forging, and the specific process may be applied to the metal body heated before forging, the metal body generating heat during forging, or the metal body that has generated heat by forging.
In addition, an object-processing device of a second aspect of the present disclosure includes: a power source; and an electrode that is connected to the power source and comes into contact with an object to be processed.
In the second aspect of the present disclosure, the power source may be configured to cause free electrons in the object to be processed to be emitted to the outside by being connected to the object to be processed through the electrode.
In the second aspect of the present disclosure, the power source may be configured to collect the free electrons emitted to the outside from the object to be processed.
In the second aspect of the present disclosure, no other power source that supplies an electric current to the object to be processed has to be provided.
In the second aspect of the present disclosure, the object to be processed may be a metal body heated before forging, a metal body generating heat during forging, or a metal body that has generated heat by forging.
According to the present disclosure, since the power source is connected to the object to be processed, it is possible to further limit the structural change and deformation of the object to be processed (object) compared with the conventional technique or to more appropriately cool the object to be processed.
In addition, if the object to be processed is a metal material (metal body) that generates heat by forging, since electrons are removed from the metal material by connecting the power source to the metal material before forging, it is possible to forge the metal material at a lower temperature than that of a metal material from which electrons have not been removed.
Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings.
First, a forged product-cooling device R of this embodiment will be described with reference to
Note that the forged product-cooling device R corresponds to an object-processing device of the present disclosure. In addition, the above forged product X corresponds to an object to be processed (object) of the present disclosure. Furthermore, the cooling process and a transformation-limiting process that the forged product-cooling device R applies to the forged product X correspond to a specific process of the present disclosure.
The forged product X is made of a predetermined metal material and is, for example, a prototype material of a blisk (product). As is well known, a blisk is a substantially circular disk-shaped rotating body in which a rotor disk and a blade of a turbo machine are integrally molded, and is, for example, a component of a compressor or/and a turbine of a gas turbine. Such a blisk is manufactured as a final product by cutting a prototype material obtained through plastic deformation working such as forging. Note that when the forged product X is a blisk, the above metal material is, for example, a titanium alloy having a predetermined composition.
The forged product-cooling device R of this embodiment is a device that applies the cooling process to the forged product X by connecting the power source to the forged product X. Among the components of the forged product-cooling device R, the electrode 1 is a needle-shaped terminal connected to one terminal of the first switch 2 through an electric wire (power line) and is made of metal having a relatively low electrical resistance such as platinum (Pt).
As shown in the diagram, the electrode 1 is disposed on the forged product X in a state of being electrically connected to the forged product X, for example, in a state of being in contact with the surface of the forged product X. The electrode 1 is electrically connected to one terminal of the first switch 2 through a flexible electric wire. Therefore, it is possible to easily dispose the electrode in a suitable place of the forged product X according to the shape, attitude and the like of the forged product X. Note that one or a plurality of electrodes 1 are provided, and an appropriately needed number of the electrodes 1 are connected to the surface of the forged product X according to the shape, attitude and the like of the forged product X.
The first switch 2 is an open/close switch that is controlled by the controller 12, one terminal of the first switch 2 is connected to each electrode 1, and the other terminal of the first switch 2 is connected to one end of the first resistor 3 and one end of the third resistor 8. The first resistor 3 has a predetermined resistance value (for example, 100Ω), one end of the first resistor 3 is connected to the other terminal of the first switch 2 and one end of the third resistor 8, and the other end of the first resistor 3 is connected to one end of the capacitor block 4.
The capacitor block 4 is a two-terminal circuit in which a plurality of capacitors each having a predetermined electrostatic capacity (for example, 0.1 μF) are connected in parallel, one end of the capacitor block 4 is connected to the other end of the first resistor 3, and the other end of the capacitor block 4 is connected to one terminal of the second switch 5. As will be described later, the capacitor block 4 is configured to cause free electrons in the forged product X to be emitted to the outside by being electrically connected to the forged product X through the electrode 1 and to collect the free electrons emitted to the outside from the forged product X. The second switch 5 is an open/close switch that is controlled by the controller 12, one terminal of the second switch 5 is connected to the other end of the capacitor block 4, and the other terminal of the second switch 5 is connected to one terminal of the third switch 6, the other terminal of the fourth switch 9, and the negative terminal of the DC power supply 11.
The third switch 6 is an open/close switch that is controlled by the controller 12, one terminal of the third switch 6 is connected to the other terminal of the second switch 5, the other terminal of the fourth switch 9 and the negative terminal of the DC power supply 11, and the other terminal of the third switch 6 is connected to one end of the second resistor 7. The second resistor 7 has a predetermined resistance value (for example, 100Ω), one end of the second resistor 7 is connected to the other terminal of the third switch 6, and the other end of the second resistor 7 is grounded.
The third resistor 8 has a predetermined resistance value (for example, 10Ω), one end of the third resistor 8 is connected to the other terminal of the first switch 2 and one end of the first resistor 3, and the other end of the third resistor 8 is connected to one terminal of the fourth switch 9 and one terminal of the fifth switch 10. The fourth switch 9 is an open/close switch that is controlled by the controller 12, one terminal of the fourth switch 9 is connected to the other end of the third resistor 8 and one terminal of the fifth switch 10, and the other terminal of the fourth switch 9 is connected to the other terminal of the second switch 5, one terminal of the third switch 6 and the negative terminal of the DC power supply 11.
The fifth switch 10 is an open/close switch that is controlled by the controller 12, one terminal of the fifth switch 10 is connected to the other end of the third resistor 8 and one terminal of the fourth switch 9, and the other terminal of the fifth switch 10 is connected to the positive terminal of the DC power supply 11. The DC power supply 11 is a power supply that generates a predetermined DC voltage (for example, 16 V), the positive terminal of the DC power supply 11 is connected to the other terminal of the fifth switch 10, and the negative terminal of the DC power supply 11 is connected to the other terminal of the second switch 5, one terminal of the third switch 6 and the other terminal of the fourth switch 9.
The controller 12 is a device that controls the first to fifth switches 2, 5, 6, 9 and 10 based on operation signals input from the operation unit 13. The controller 12 is a logic circuit or a software control device that generates opening/closing control signals for each of the first to fifth switches 2, 5, 6, 9 and 10 based on the operation signals. In a case where the controller 12 is a software control device, the controller 12 includes a central processing unit (CPU), various storage devices, and an input/output device. The controller 12 controls the operations of the first to fifth switches 2, 5, 6, 9 and 10 into desired states by appropriately generating the opening/closing control signals based on the operation signals.
The operation unit 13 is a device that receives operation instructions of a manager in charge of the forged product-cooling device R and is, for example, one or a plurality of operation buttons. The operation unit 13 outputs operation signals according to the operation instructions to the controller 12.
Next, a forging device T of this embodiment will be described with reference to part (a) of
The upper mold B is a ring-shaped member in which a cavity is provided in a center part thereof, and includes a third pressing surface e (wave-shaped surface) facing the second pressing surface c (wave-shaped surface) and an outer cylindrical surface f facing the inner cylindrical surface d. The third pressing surface e is formed in a wave shape. The outer cylindrical surface f is an inner peripheral surface of the upper mold B. In the upper mold B, the third pressing surface e faces the second pressing surface c of the lower mold A at a first distance La, and the outer cylindrical surface f faces the inner cylindrical surface d at a second distance Lb. A space disposed between the inner cylindrical surface d of the lower mold A and the outer cylindrical surface f of the upper mold B is a base material accommodation space Kb that accommodates a base material Xa (described below), and a space disposed between the second pressing surface c and the third pressing surface e is an extrusion space Ko.
Note that a reference sign Xa in part (a) of
The pressing upper mold C is a substantially circular disk-shaped member in which an annular protruding part g is provided on a peripheral edge of one surface thereof. In the pressing upper mold C, the end surface (flat surface, lower surface) of the protruding part g is a pressing surface h that comes into contact with and presses the upper surface (one end surface) of the base material Xa. The pressing upper mold C is supported by a pressing mechanism (not shown) and moves up and down by the pressing device to press the upper surface of the base material Xa downward.
Next, a method of manufacturing the forged product X using the forged product-cooling device R and the forging device T will be described in detail with reference to part (b) of
A manufacturing step of the forged product X using the forging device T includes a forging step, a cooling step (transformation-limiting step), and a working step. Among these steps, the cooling step (transformation-limiting step) corresponds to the cooling method and the transformation-limiting method of this embodiment. First, in the forging step, as shown in part (a) of
By such pressing of the pressing upper mold C, as shown in parts (a) and (b) of
In the forging step of the base material Xa, the base material Xa deforms while generating heat. That is, the forged product X is a metal body that generates heat due to the action of an external force by the pressing upper mold C, and for example, the temperature thereof increases from 950° C. before forging up to about 1100° C. Since such a high temperature of the forged product X may transform the structure (crystal structure) of the forged product X, the forged product X has to be cooled (rapidly cooled).
Due to such a necessity, the following cooling step is performed in this embodiment. Although the details will be described later, the cooling step also corresponds to a transformation-limiting step of limiting transformation of the structure of the forged product X. In the cooling step (transformation-limiting step), as shown in part (a) of
More specifically, as shown in, for example, part (b) of
In this state, the controller 12 of the forged product-cooling device R first sets the second switch 5 and the fifth switch 10 to the closed state and sets the first switch 2, the third switch 6 and the fourth switch 9 to the opened state (first setting state). When the first state is continued for a predetermined time, each capacitor of the capacitor block 4 is gradually charged by the DC power supply 11 and becomes a fully charged state. That is, in the capacitor block 4, one end is positively charged, the other end is negatively charged, and the voltage between both ends (voltage between two terminals) becomes a voltage close to the output voltage (for example, 16 V) of the DC power supply 11.
In the first setting state, the controller 12 changes the setting of the fifth switch 10 from the closed state into the opened state and changes the settings of the first switch 2 and the third switch 6 from the opened state into the closed state (second setting state). That is, in the capacitor block 4, one end is connected to each of the electrodes 1 through the first switch 2 and the first resistor 3, and the other end is grounded through the second switch 5, the third switch 6 and the second resistor 7. In the second setting state, although a slight voltage drop occurs in the first resistor 3 and the second resistor 7, the forged product X is applied with a voltage close to the voltage between the terminals of the capacitor block 4. At this time, the capacitor block 4 is connected to the forged product X through the electrodes 1 to cause free electrons in the forged product X to be emitted to the outside and to collect the free electrons emitted from the forged product X to the outside.
Then, when the controller 12 continues the second setting state for a predetermined time, the controller 12 changes the setting of the second switch 5 from the closed state into the opened state and changes the setting of the fourth switch 9 from the opened state into the closed state (third setting state). In the third setting state, each electrode 1 is grounded through the first switch 2, the third resistor 8, the fourth switch 9, the third switch 6 and the second resistor 7.
Then, when the controller 12 continues the third setting state for a predetermined time, the controller 12 changes the setting of the second switch 5 from the opened state into the closed state (fourth setting state). That is, in the fourth setting state, one end of the capacitor block 4 is grounded through the first resistor 3, the third resistor 8, the fourth switch 9, the third switch 6 and the second resistor 7, and the other end of the capacitor block 4 is grounded through the second switch 5, the third switch 6 and the second resistor 7. When the fourth setting state has been continued for a predetermined time, the electric charge charged in the capacitor block 4 is sufficiently discharged. Then, when the controller 12 continues the fourth setting state for a predetermined time, the controller 12 repeats the above first to fourth setting states a predetermined number of times.
By connecting the capacitor block 4 (power source) by the forged product-cooling device R a predetermined number of times, free electrons in the forged product X (metal material) are collected by the outside of the forged product X, that is, the capacitor block 4 (power source) through each electrode 1 and the like. Note that in this embodiment, at the time the capacitor block 4 is connected to the forged product X, no other power source that applies a voltage to the forged product X to supply an electric current thereto, that is, that supplies electrons to the forged product X is connected thereto.
Here, since the forged product X is held by the forging device T and has an extremely high electrical resistance due to a high temperature state of about 700° C. to 1100° C., the amount of electrons (for example, free electrons in the electrodes 1) to be supplied from the electrodes 1 to the forged product X is extremely small Therefore, when the capacitor block 4 (power source) is connected to the forged product X by the forged product-cooling device R, free electrons in the forged product X are exclusively collected in the capacitor block 4 (power source).
When such connection of the capacitor block 4 (power source) is performed one or a plurality of times, the forged product X is cooled as shown in the graph (characteristic diagram) of
In this experiment, a change in the internal temperature of the forged product X when the forged product X was heated up to 800° C. in a vacuum atmosphere and then was slowly cooled was measured in each case of a case where the capacitor block 4 (power source) was connected to the forged product X (shown by a broken line and a dashed and double dotted line) and in a case where the capacitor block 4 (power source) was not connected (shown by a solid line). In addition, in this experiment, a change in the internal temperature of the forged product X was checked in each case of a case where the capacitor block 4 (power source) was connected only once (shown by the broken line) and in a case where the capacitor block 4 was connected a plurality of times (shown by the dashed and double dotted line). In a case where the capacitor block 4 was connected to the forged product X only once, the electrodes 1 were brought into contact with the forged product X only once. In a case where the capacitor block 4 was connected to the forged product X a plurality of times, contact and separation of the electrodes 1 with respect to the forged product X were repeated.
As shown in
According to this embodiment, it is possible to further limit the structural change of the forged product X compared with the conventional technique because the forged product X can be more rapidly cooled by connecting the capacitor block 4 (power source) than a case of only the conventional slow cooling. Note that in this embodiment, it can be understood that the structural change of the forged product X is not limited by cooling due to emission of free electrons from the forged product X but is limited by limiting interaction between structures (crystals) and/or atoms configuring the forged product X due to emission of free electrons from the forged product X.
That is, although it is necessary to further study whether the direct action of connecting the capacitor block 4 (power source) to the forged product X relates to the cooling based on emission of free electrons from the forged product X, the limitation of interaction between structures (crystals) or/and atoms, or other factors, as shown in
Note that the present disclosure is not limited to the above embodiment, and it is conceivable that the following modifications be adopted.
(1) In the above embodiment, the electrodes 1 are arranged at the four points P1 to P4 as shown in part (b) of
(2) In the above embodiment, the cooling step (transformation-limiting step) is performed after the forging step, but the present disclosure is not limited to this. For example, the cooling step (transformation-limiting step) may be performed during the forging step. That is, the electrode 1 may be brought into contact with the base material Xa during the forging step before the forged product X is completed, for example, be brought into contact with the base material Xa generating heat during forging using the pressing upper mold C, and the capacitor block 4 (power source) may be connected to the base material Xa, whereby the base material Xa may be cooled. When the power source is connected to the base material Xa generating heat during forging, it is possible to effectively remove high-energy electrons generated by the heat generation from the base material Xa.
In addition, the electrode 1 may be brought into contact with the base material Xa heated before forging to connect the capacitor block 4 (power source) to the base material Xa. When the power source is connected to the base material Xa heated before forging, it is possible to remove electrons from the base material Xa in advance and to forge the base material Xa at a lower temperature by 20° C. to 30° C. than a base material (metal material) from which electrons have not been removed. The reason for this is considered to be because the lattices of atomic nuclei have the energy that electrons have, and the deformation resistance decreases even at the same temperature.
The cooling step (transformation-limiting step) may be performed at an appropriate timing according to the temperature of the base material Xa. If the temperature has become too low, it may be reheated to a temperature suitable for forging in an insulation state where no electrons enter. After heating the base material Xa, the base material Xa may be cooled by connecting the power source thereto, and then after reheating it in the insulation state, forging may be performed thereon.
(3) In the above embodiment, the capacitor block 4 in which a plurality of capacitors are connected in parallel is adopted, but the present disclosure is not limited to this. For example, various secondary batteries may be adopted therefor. In addition, in the above embodiment, a single capacitor block 4 is used, but a plurality of capacitor blocks 4 may be used. For example, the capacitor block 4 may be connected to the forged product X a plurality of times by sequentially connecting a plurality of capacitor blocks 4 to the electrode 1 in a predetermined order.
(4) Although the output voltage of the DC power supply 11 was set to 16 V in the experimental results shown in
(5) In the above embodiment, the forged product-cooling device R is adopted including the electrodes 1, the first switch 2, the first resistor 3, the capacitor block 4, the second switch 5, the third switch 6, the second resistor 7, the third resistor 8, the fourth switch 9, the fifth switch 10, the DC power supply 11, the controller 12 and the operation unit 13, but the present disclosure is not limited to this. The configuration of the forged product-cooling device R is just an example, and other configurations may be adopted.
(6) In the above embodiment, the forged product X is manufactured from the base material Xa made of a predetermined metal material, but the present disclosure is not limited to this. For example, as shown in
(7) Although the above embodiment relates to a case where the present disclosure is applied to the limitation of the structural change of the forged product X, the application of the present disclosure is not limited to this. The present disclosure is applicable to various metal objects having free electrons thereinside. In addition, since the essential means of the present disclosure is to connect the power source to an object to be processed (object), the resulting specific process is not limited to the cooling of the object to be processed (object) or the limitation of interaction between the structures thereof.
As the specific process of the present disclosure, for example, the cooling process of cutting tools can be considered. Although a cutting tool has a high temperature due to friction with a material to be cut, it is possible to easily cool the cutting tool by connecting the cutting tool to the power source. That is, it is possible to easily limit deterioration in the hardness or the like of the cutting tool due to an increase in temperature.
In addition, as the specific process of the present disclosure, for example, the solution treatment of metal materials can be considered. A metal material such as nickel alloys and titanium alloys is increased in strength through densifying the structure thereof by increasing the temperature thereof to be high and then rapidly cooling, and it is possible to easily and rapidly cool the metal material by connecting the power source to the metal material. In the conventional method, when the metal material is heated to a high temperature and then rapidly cooled, the temperature difference between the surface and the inside of the metal material may increase, and a large residual stress may be generated, which may deform the metal material. On the other hand, according to the present disclosure, it is possible to rapidly cool the entire body including the inside of the metal material while reducing the temperature difference between the surface and the inside, and thus to perform a high quality solution treatment.
In addition, it is conceivable that a metal material heated for the solution treatment be connected with the power source, electrons be removed from the metal material in advance, and thereafter another cooling means rapidly cool the metal material. Even in this case, it is possible to reduce the residual stress and to limit the deformation of the metal material.
(8) In the above embodiment, the first to fourth setting states are repeated a predetermined number of times, but the present disclosure is not limited to this. For example, the third and fourth setting states may be omitted, and the first and second setting states may be repeated a predetermined number of times.
The present disclosure can be used, for example, to further limit the structural change or deformation of an object made of metal compared with the conventional technique, or to more appropriately cool the object.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2018-049818 | Mar 2018 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2019/007819 | 2/28/2019 | WO | 00 |
