JPWO2005068167A1 - Method and apparatus for heating and pressurizing articles via a liquid heat / pressure transmission medium - Google Patents

Abstract

There is provided a method and apparatus for pressurization and heat treatment that can apply pressure to an article with certainty by applying pressure and heat treatment to the article via a heat / pressure transmission medium maintained in a liquid state. . The apparatus is a container (2) provided with a lid for sealing or opening a cavity so as to be able to contact and separate, and a flow path (7) communicating with the lid (2a) between the cavity and the outside of the container. ) Having a container (2) having one end thereof, a conduit (13) connected to the outer end of the flow path (7) at one end, and being connected to the other end of the conduit (13) and separated from the container. An external pressure booster (5) for accommodating a pressure medium therein, an external pressure booster for pressurizing a heat / pressure transmission medium in the cavity via the pressure medium, a container, an external pressure booster, and the pipe line And a heater (10) for heating the heat / pressure transmission medium and the pressure medium.

Description

  The present invention relates to a method and an apparatus for pressurizing and heating an article by a high temperature isotropic compression (HIP) method, and in particular, a casting or metal obtained by casting a molten metal (aluminum, magnesium, cemented carbide, or these A ceramic sintered body and a densified casting are manufactured by pressurizing and heating a compact of a ceramic powder (including a metal mixture) or a ceramic powder by a high-temperature isotropic compression method through a liquid heat / pressure transmission medium. It relates to a method and a device.

Conventionally, an apparatus for processing an article by a high temperature isotropic compression (HIP) method via a liquid heat / pressure transmission medium (molten salt, molten glass, etc.) or a high temperature isotropic compression molding of a molded body is known. (JP 2001-262295 A, JP 49-123409 A, JP 6-226428 A).

  However, the apparatus described in Japanese Patent Application Laid-Open No. 2001-262295 has a molten salt that is a heat / pressure transmission medium and a work piece (light alloy casting) placed in a container, and the container is covered with a lid. In other words, the workpiece is hot isobarically pressed by inserting a piston into the molten salt through a hole and pressurizing the molten salt. Since this piston is thin, it is necessary to penetrate deeply into the molten salt in order to sufficiently pressurize the molten salt. Therefore, in order to prevent the piston from interfering with the workpiece, the length of the container needs to be considerably longer than the length of the workpiece, and there is a problem that the container becomes large.

  In addition, all of the apparatuses described in Japanese Patent Application Laid-Open Nos. 49-123409 and 6-226428 are punches (pistons) that enter the cavity in order to compress the molten salt in the die (sleeve) cavity. ). The punch diameter is the same as the cavity diameter. Therefore, when the workpiece becomes large, it is necessary to increase the diameters of the cavity and the punch. As a result, a large pressure device is required to apply a large pressing force to the punch. Since a strong support device for supporting is required, the cost is high and it is not practical.

  Furthermore, an apparatus described in Japanese Patent Application Laid-Open No. 6-226428 has a metal sheet placed on the upper surface of a die and the upper surface of a pressurized medium (molten salt), and the pressed medium is pressed by pressing these sheets. Pressurized. When pressed, the sheet will be plastically deformed and will be discarded. Therefore, there is a problem in that it is necessary to replace the sheet, which requires cost and labor.

  The object of the present invention is to overcome the above-mentioned problems. In order to achieve this object, a method for heating and pressurizing an article using a liquid heat / pressure transmission medium according to the first aspect of the present invention includes a cavity having a cavity in which the article can be sealed. The article is placed in the container, the cavity is filled with a liquid heat / pressure transmission medium, and the article is pressurized and heated using the liquid heat / pressure transmission medium by pressurizing and heating the heat / pressure transmission medium. In the method, the pressurization of the heat / pressure transmission medium is performed by using a pressure medium which is completely liquefied with the same component as the heat / pressure transmission medium by an external pressure intensifier connected to the cavity via a pipe line. Made through.

  The method for pressurizing and heating an article using a liquid heat / pressure transmission medium according to the second aspect of the present invention is to put the article into the cavity of a container having a cavity into which the article can be sealed, A method for pressurizing and heating an article using a liquid heat / pressure transmission medium for filling a cavity with a liquid heat / pressure transmission medium and pressurizing and heating the heat / pressure transmission medium, wherein the heat / pressure The pressure of the transmission medium is generated by an external pressure booster connected to the cavity via a separator, and the generated pressure is applied with the same components as the heat / pressure transmission medium in the separator. The pressure medium and the pressure medium that is separated from the pressure medium and transmitted to the pressure medium that is accommodated, and the transmitted pressure is transmitted to the pressure medium, whereby the pressure in the cavity is increased. Add heat / pressure transmission medium It is intended to.

  In the method according to the first and second aspects, the article can be pressurized without using a punch (piston), and the pressure generated by the external pressure intensifier can be applied to the article in the cavity quickly and reliably. it can.

  In particular, in the method according to the second aspect, the pressurizing medium and the pressure transmission medium are isolated from each other by an elastic isolation member, and the isolation member is extended by press-fitting the pressure transmission medium into the separator. Thus, pressure is transmitted from the pressure transmission medium to the pressure medium. As a result, the pressure generated by the external pressure booster can be accurately and instantaneously propagated to the heat / pressure transmission medium. In the method according to the second aspect of the present invention, the pressure transmission medium can be a low melting point alloy, whereby the heating in the external pressure booster can be kept at a relatively low temperature.

  Furthermore, in the method of the second aspect of the present invention, the pressure transmission medium can be an industrial oil that is liquid at normal temperature and pressure. Thereby, it is not necessary to heat the external pressure booster, and energy for heating can be minimized.

  In the method according to the first and second aspects of the present invention, the melting point of the heat / pressure transmission medium is equal to or lower than the heating temperature of the article. Thereby, heating / pressurizing treatment can be performed without dissolving the article.

  In the method for pressurizing and heating an article using the liquid heat / pressure transmission medium in the first and second aspects of the present invention, the melting point of the heat / pressure transmission medium is set to be equal to or lower than the heating temperature of the article. Can do. Thereby, pressurization and heat treatment can be performed without dissolving the article.

  In the method for pressurizing and heating an article using the liquid heat / pressure transmission medium according to the first and second aspects of the present invention, the heat / pressure transmission medium may be nitrate or nitrite alone or a mixed salt of nitrate. Alternatively, a mixed salt of nitrite or a mixed salt of nitrate and nitrite can be used.

  In the method for heating and pressurizing an article using the liquid heat / pressure transmission medium according to the first and second aspects of the present invention, the article is a molded article containing at least one of a casting, a metal powder, or a ceramic powder. It is possible to form a dense cast or sintered body by heating and pressurizing the cast or the compact. Thus, the method of the present invention can be applied to a wide range of articles such as castings, metal powders, and ceramic powders.

  Further, in the method for pressurizing and heating an article using the liquid heat / pressure transmission medium according to the first and second aspects of the present invention, the heating of the heat / pressure transmission medium in the cavity is arranged around the container. The outer periphery of the heater can be covered with a heat insulating material. Thereby, the heat / pressure transmission medium in the cavity can be efficiently heated.

  In order to achieve the above object, an apparatus for heating and pressurizing an article using a liquid heat / pressure transmission medium according to the first aspect of the present invention includes a cavity, and heat / pressure transmission between the article and the liquid in the cavity. An apparatus for heating and pressurizing the article by heating and pressurizing the heat and pressure transmission medium of the liquid in a sealed manner, and having a lid for sealing or opening the cavity so as to be able to contact and separate A container having a flow path communicating between the cavity and the outside of the container at the lid, a pipe line connected to the external end of the flow path at one end, and the pipe line An external pressure intensifier connected to the other end of the container and separated from the container and containing a pressurizing medium therein, and the heat / pressure transfer medium in the cavity is applied via the pressurizing medium. An external pressure booster that presses and the container Comprising a heater for the external pressure intensifier and provided in the conduit for heating the heat-pressure transmission medium and the pressurizing medium.

  An apparatus for pressurizing and heating an article using a liquid heat / pressure transmission medium according to the second aspect of the present invention includes a cavity, and the article and the liquid heat / pressure transmission medium are sealed in the cavity. An apparatus for pressurizing and heating the article by pressurizing and heating the heat / pressure transmission medium, wherein the container is provided with a lid for sealing or opening the cavity so as to be able to contact and separate. The lid includes a container having a flow path communicating between the cavity and the outside of the container, a first conduit connected to the external end of the flow path at one end, and a medium containing chamber inside. The medium storage chamber is separated into a pressurization medium storage chamber and a pressure transmission medium storage chamber by an extendable isolation member, and the other end of the first pipe and the pressurization medium storage chamber are connected in communication. And a first end connected in communication with the pressure transmission medium storage chamber at one end. An external pressure intensifier connected to the other end of the pipe and the second pipe and separated from the container and containing the pressure transmission medium therein, the pressure increasing medium via the pressure transmission medium An external pressure booster that propagates pressure to the pressure medium to pressurize the heat / pressure transmission medium in the cavity, and the container, the separator, the external pressure booster, the first pipe line, and the second pipe line. And a heater for heating the heat / pressure transmission medium, the pressure medium, and the pressure transmission medium.

  By configuring the apparatus of the first and second aspects, it becomes possible to heat and pressurize an article (workpiece) of a certain size without using a large apparatus, and a metal disposable Since no sheet is required, it is possible to reduce the labor and cost of sheet replacement.

  In the apparatus for pressurizing and heating an article using the liquid heat / pressure transmission medium in the second aspect of the present invention, the isolation member in the medium accommodating chamber can be a metal bellows whose one end is closed, The open end side of the metal bellows can be brought into close contact with the inner wall of the medium housing chamber to make the inside of the metal bellows the pressure transfer medium housing chamber. As a result, the pressure medium and the pressure transmission medium can be isolated from each other so as not to be mixed, and a predetermined pressure can be reliably transmitted to the pressure medium.

  In the apparatus according to the first and second aspects, the container lid has a conical air pocket whose bottom is the bottom and the diameter of the bottom circle is equal to the diameter of the cavity, and the side wall of the lid is externally attached. A flow path having an end and an inclined surface of the air reservoir as an internal end, and an air passage having an apex of the air reservoir as an internal end and the side wall of the lid as an external end are respectively formed through. As a result, the heat / pressure transmission medium can be easily introduced from the outside of the container into the cavity, and a small amount of air trapped in the cavity of the container during the heating / pressurizing process of the article can be easily released to the outside. Can be released.

  The apparatus according to the first and second aspects further includes a frame surrounding the container, and fixing means provided between a lower end of the container and an inner bottom surface of the frame, and the fixing means is in the cavity. When the heat / pressure transmission medium is pressurized, the container is pushed up to press the upper surface of the lid against the ceiling surface of the frame, against the force acting on the lid from the heat / pressure transmission medium. Fix the lid. Thereby, even if the article in the cavity is pressurized with the heat / pressure transmission medium, the lid of the container can be securely fixed.

  Further, in the apparatus of the first and second aspects, a heater for heating the heat / pressure transmission medium in the cavity is provided in the container or in the cavity, and the outer periphery of the heater is Covered with insulation. Thereby, the heat / pressure transmission medium in the cavity can be efficiently heated.

  The best mode for carrying out the present invention (Examples 1 and 2) will be described below. These forms are described by way of example only and are not intended to limit the invention to such forms. In Examples 1 and 2, like elements of the apparatus are given the same or similar numbers.

  The present invention relates to a method and apparatus for heating and pressurizing an article by a high temperature isotropic compression (HIP) method, and in particular, a high temperature isotropic compression method using a liquid heat / pressure transmission medium for a metal powder or ceramic powder compact. The present invention relates to a method and an apparatus for manufacturing a sintered body. The present invention also relates to a method and apparatus for producing a dense and high-quality casting by minimizing or eliminating voids contained in the casting by similarly treating a casting obtained by casting molten metal.

  Here, the article in the present invention includes a compact or casting of metal powder or ceramic powder. The metal powder includes aluminum, magnesium, cemented carbide or a mixture of these metals.

  In addition, the heat / pressure transmission medium and the pressure medium in the present invention are simple salts of nitrates such as potassium nitrate (melting point 333 ° C.) and sodium nitrate (melting point 308 ° C.) and nitrites such as sodium nitrite (melting point 271 ° C.). It means a molten salt which is a salt, a mixed salt of nitrates, a mixed salt of nitrites, or a mixed salt of nitrate and nitrite. However, the melting point of the molten salt needs to be lower than the temperature at which the article is heated.

  Furthermore, the heater in the present invention is generally one that generates heat when energized, for example, a structure in which a nichrome wire is covered with an insulator, but is not limited to this, and a heater that can exhibit the same function. Are all included. Moreover, the heat insulating material in this invention means what is normally used in industrial machines, such as a ceramic heat insulating material.

  The external pressure booster in the present invention has a bore capable of storing molten salt as a pressurized medium, and communicates with the bore by inserting a plunger into the molten salt stored in the bore. It means what has a function which can pump molten salt from the established discharge outlet.

  Furthermore, the fixing means in the present invention has a mechanism that generates a pressure that can be opposed to the applied pressure applied to the cavity during pressurization and heat treatment of the article. Specifically, a hydraulic cylinder is most preferable. An electric cylinder can also be used.

Example 1
A first embodiment of an apparatus for carrying out the present invention is shown in FIG. FIG. 1 shows a pressure of a frame 1 of the present invention and a heat / pressure transmission medium (molten salt in this embodiment) connected to the frame 1 and filled in a cavity 3 of a container 2 accommodated in the frame 1. It is a schematic sectional drawing which shows the external pressure booster 5 pressurized via a medium (molten salt of the same component as a heat / pressure transmission medium in a present Example).

  The container 2 has a cup shape having a cavity 3, and is provided with a lid 2a for sealing or opening the cavity 3 so as to be able to contact and separate. The container 2 is supported by contacting the upper end of a hydraulic cylinder 6 as a fixing means whose bottom surface is fixed to the inner bottom surface of the frame 1. Since the lid 2a can be carried into and out of the frame 1 by a conveying device (not shown), the cavity 3 of the container 2 can be sealed or opened.

  The lid 2 a is formed with a conical air pocket 8 having a bottom surface of the lid 2 a as a skirt and a bottom circle diameter equal to the diameter of the cavity 3. The apex of the air reservoir 8 is located substantially on the longitudinal center axis of the lid 2a. When the container 2 is covered with the lid 2a, the cavity 3 and the air reservoir 8 are heated and pressurized. Thus, a space is formed. The lid 2a is provided with a flow path 7 for allowing molten salt as a pressurized medium to flow in. The flow path 7 extends horizontally straight with the side wall of the lid 2a as an external end, and the lid 2a The inclined surface of the air reservoir 8 that is bent at a right angle downward from the center of 2a and forms the bottom surface of the lid 2a passes through the inner end as an inner end. The lid 2a is provided with an air passage 9 extending straight upward with the apex of the air reservoir 8 as an inner end, then bent at a right angle and extending straight, and penetrating the side wall of the lid 2a as an outer end. . Since the air passage 9 is connected to a valve (not shown) at its outer end, the air accumulated in the air reservoir 8 can be discharged to the outside by opening the valve.

  A heater 10 is mounted on the outer circumference of the container 2 and the lid 2a so that the pressurized medium in the flow path 7 and the heat / pressure transmission medium in the cavity 3 can be heated. It has become. The heater 10 is mounted on the lid 2a so as to avoid the opening which is the outer end of each of the flow path 7 and the air path 9. The heater 10 has a structure in which a nichrome wire is covered with an insulator, and since the outer periphery of the heater 10 is covered with a heat insulating material 11, heat generated by the heater 10 is prevented from being transmitted to the outside. Can do.

  An external pressure booster 5 is installed separately from the frame 1, and the external pressure booster 5 has a bore 4 for filling a molten salt as a pressure medium therein. A discharge port 12 communicating with the bore 4 is formed in the bottom surface of the external pressure booster 5, and the external pressure booster 5 includes a ram 5 a that can be inserted into the bore 4. Furthermore, the heater 10 is attached to the outer periphery of the external pressure booster 5, the outer periphery of the heater 10 is covered with the heat insulating material 11, and the discharge port 12 and the outer end of the flow path 7 are connected to a pipe. A communication connection is established by a path 13. Accordingly, the molten salt as the pressurizing medium stored in the bore 4 can be heated to a predetermined temperature or more, and the molten salt discharged from the bore 4 of the external pressure booster 5 is sent into the flow path 7. Can do. Although omitted in FIG. 1, the outer periphery of the conduit 13 is actually mounted with the heater 10 over almost the entire length, and the outer periphery of the heater 10 is covered with the heat insulating material 11. Therefore, the molten salt as the pressurized medium discharged from the external pressure booster 5 can reach the flow path 7 while maintaining a predetermined temperature.

  A method for heating and pressurizing the aluminum casting M as an article as an example will be described below using the apparatus configured as described above. First, in a state where the lid 2a and the container 2 are separated from each other, a predetermined amount of molten salt as a heat / pressure transmission medium that is heated in advance into the cavity 3 to be liquid is injected. As the molten salt in this case, a commercially available composite salt having a melting point of 145 ° C. (trade name “Baslick”) manufactured by Sankei Metallurgical Industry Co., Ltd. was used. Next, the container 2 is heated by the heater 10 to increase the temperature of the molten salt injected into the cavity 3, and finally reaches 520 ° C. which is a temperature necessary for the densification treatment of the aluminum casting M. To maintain that temperature. In this state, the aluminum casting M heated to a predetermined temperature (520 ° C.) is immersed in the molten salt in the cavity 3. Thereafter, the lid 2a is moved immediately above the container 2 by a transport device (not shown), and then the hydraulic cylinder 6 as a fixing means is operated to push up the container 2, and the upper surface of the lid 2a is The container 2 and the lid 2a are pressed and pressed against the ceiling surface so that the close contact between the lid 2a and the container 2 can be maintained even when the molten salt in the cavity 3 is pressurized. At this time, a very small amount of air is trapped in the air reservoir 8 and is released to the outside by opening a valve (not shown) connected to the outer end of the air passage 9.

  Subsequently, the inside of the flow path 7 formed in the lid 2a, the inside of the pipe line 13 and the inside of the bore 4 of the external pressure booster 5 are pressurized by an injection device (not shown) connected to the pipe line 13 in communication. Fill with molten salt as medium. The molten salt has the same components as the heat / pressure transmission medium. Then, the heater 10 attached to the lid 2a in which the flow path 7 is formed, the pipe line 13 and the external pressure booster 5 are respectively heated to a temperature equal to or higher than the melting point of the molten salt (180 ° C. in this embodiment). ), The molten salt in the flow path 7, the pipe line 13, and the bore 4 are all completely in a liquid state.

  Thereafter, the ram 5a of the external pressure intensifier 5 is caused to enter the molten salt in the bore 4 by a pressure cylinder (not shown), and a predetermined pressure (about 120 MPa in this embodiment) is applied to the molten salt. Then, since the molten salt is completely in a liquid state, the predetermined pressure applied is applied as the heat / pressure transmission medium in the cavity 3 via the molten salt in the pipe line 13 and the flow path 7. The aluminum salt M is instantly propagated to the molten salt, and a predetermined pressure (about 120 MPa) acts on the aluminum casting M in the cavity 3, whereby the voids of the aluminum casting M are refined or disappeared and densified. Is done. During the pressurization, when the liquid level of the molten salt in the cavity 3 rises and fills the air reservoir 8, the molten salt passes from the air passage 9 communicating with the air reservoir 8 to the container 2. Although leakage starts to the outside, in this case, leakage of the molten salt is stopped by closing the valve (not shown) connected to the air passage 9.

  Here, the reason why the molten salt as the pressurizing medium is completely liquefied is that the pressure cannot be accurately transmitted to the heat / pressure transmitting medium in the cavity 3 unless it is completely liquid. is there. That is, if a part of the pressurizing medium is not liquid, only a part of the pressure applied by the external pressure booster 5 is propagated to the heat / pressure transmission medium in the cavity 3. Accordingly, in order to propagate the required pressure, a higher pressure needs to be generated by the external pressure booster 5, and thus a larger apparatus is required. Another reason is that if the pressure medium in the bore 4 is not in a liquid state, a predetermined pressure cannot be generated even if the ram 5a is entered.

  In order to keep the molten salt as the pressurizing medium in the flow path 7, the pipe line 13 and the bore 4 in a liquid state, the molten salt as the heat / pressure transmission medium in the cavity 3 is not enough. It is not necessary to raise the temperature, and it is sufficient if the temperature is higher than the melting point of the molten salt. Therefore, molten salt having a temperature lower than that of the molten salt in the cavity 3 flows from the flow path 7 into the air reservoir 8 during the pressurizing process, but the volume of the air reservoir 8 is larger than that of the cavity 3. Therefore, the temperature of the molten salt in the cavity 3 hardly decreases, and the heat treatment of the aluminum casting M is not affected.

  Next, Example 2 of the present invention will be described below.

  In the second embodiment, the melting point of the pressure transmission medium can be made lower than the melting points of the heat / pressure transmission medium and the pressure medium, for example, hydraulic oil, gear oil, lubricating oil, cutting oil, cleaning, which are highly nonflammable. This means the use of industrial oils that are liquid at room temperature and normal pressure (25 ° C., 1 atm) such as oil, and low melting point alloys such as bismuth, lead, and tin having a melting point of 70 to 140 ° C.

  Further, the separator in the second embodiment includes a medium storage chamber for storing the pressurizing medium and the pressure transmission medium therein, and the medium storage chamber cannot mix the pressurization medium and the pressure transfer medium. Further, it means a pressure vessel having a structure that is isolated by a telescopic isolation member so that pressure can be transmitted from the pressure transmission medium to the pressure medium. The pressure transmission medium accommodation chamber accommodating the pressure transmission medium is connected to the external pressure booster. When the pressure transmission medium is pumped from the external pressure booster into the pressure transmission medium accommodation chamber, the isolation member extends. Then, the pressure is propagated to the pressurizing medium in the pressurizing medium containing chamber containing the pressurizing medium, and the pressurized medium is discharged out of the separator. The size and shape of the separator are not particularly limited, and are appropriately selected according to the heating and pressurizing temperatures for processing the article.

  The telescopic isolation member means that the pressure transfer medium propagates pressure to the pressurizing medium by extending when the pressure transfer medium is pumped into the pressure transfer medium accommodating chamber by the external pressure booster, and the first pipe A passage and a function of transmitting the pressure to the heat / pressure transmission medium in the cavity 3 by the pressure medium filled in the flow path, and the pressure medium accommodation chamber and the pressure transmission medium accommodation chamber, respectively. In addition, the pressure medium and the pressure transmission medium are separated from each other, and the function of not allowing the liquid to pass through to make the both unmixable is also provided. Specifically, a metal bellows or a diaphragm is suitable.

  A second embodiment of the apparatus for carrying out the present invention is shown in FIG. FIG. 2 shows a frame 1 and a heat / pressure transfer medium (molten salt in this embodiment) filled in a cavity 3 of a container 2 connected to the frame 1 and housed in the frame 1. In the embodiment, the external pressure booster 5 that pressurizes via the molten salt), the pressure transmission medium discharged from the external pressure booster 5 and the pressure medium are isolated, and the pressure is transmitted to the pressure medium by the pressure transmission medium. It is a schematic sectional drawing which shows the separator 20 which does.

  2, the frame 2, the container 2 and its lid 2 a, the cavity 3, the hydraulic cylinder 6 as a fixing means fixed to the inner bottom surface of the frame 1, and the lid 2 a for flowing the molten salt as the pressure medium. Heated through the perforated flow path 7, the conical air reservoir 8, the air passage 9 passing through the side wall of the lid 2a as an external end and connected to a valve (not shown), the outer periphery of the container 2 and the lid 2a The heat insulating material 11 which coat | covers the container 10 and the outer periphery of the said heater 10 makes the same effect | action as what is shown in FIG. Description of these elements again is omitted.

  A separator 20 having a medium storage chamber 21 is provided inside the frame 1 separately from the frame 1. The medium accommodating chamber 21 is isolated from the pressurized medium accommodating chamber 22 and the pressure transmission medium accommodating chamber 23 by a metal bellows 17 as an isolating member that is extendable and closed at one end. The metal bellows 17 is in close contact with the inner wall of the medium housing chamber 23 at the open end side, and the inside of the metal bellows 17 serves as the pressure transmission medium housing chamber 23. The pressure transfer medium accommodation chamber 23 is formed in the wall surface of the separator 20 and the pressure transfer medium is introduced via the pressure transfer medium introduction port 16 that communicates the inside of the pressure transfer medium accommodation chamber 23 and the outside of the separator 20. A pressure transfer medium can be introduced into the storage chamber 23. The pressurizing medium storage chamber 22 and the flow path 7 are connected in communication via a first pipe line 13a. That is, one end of the first pipe line 13a is connected to the external end of the flow path 7 and the other end is formed in the wall surface of the separator 20 so that the inside of the pressurized medium storage chamber 22 and the outside of the separator 20 are connected. Is connected to the pressurized medium discharge port 15 which communicates with the pressurized medium discharge port 15, so that the pressurized medium containing chamber 22 and the flow path 7 are connected to each other. Further, since the heater 10 is mounted on the outer periphery of the separator 20 and the outer periphery of the heater 10 is covered with the heat insulating material 11, the pressurized medium and the pressure transmission medium in the medium storage chamber 21 are provided. Are kept at a predetermined temperature.

  An external pressure booster 5 is installed separately from the frame 1, and the external pressure booster 5 is formed with a bore 4 for filling industrial oil (hydraulic hydraulic oil in this embodiment) as a pressure transmission medium. Has been. A pressure-transfer medium discharge port 12 communicating with the inside of the bore 4 is formed through the bottom surface of the external pressure booster 5, and the external pressure booster 5 includes a ram 5 a that can be inserted into the bore 4. . The pressure transfer medium introduction port 16 and the pressure transfer medium discharge port 12 of the separator 20 are connected to each other via a second pipe 18.

  Accordingly, the industrial oil as a pressure transmission medium stored in the bore 4 is pushed out from the bore 4 of the external pressure booster 5 through the pressure transmission medium discharge port 12 and the second pipe 18 and the pressure transmission medium introduction port 16. The pressure can be fed into the pressure transmission medium accommodating chamber 23 through the through hole. A heater 10 is attached to the outer periphery of the external pressure booster 5, and the outer periphery of the heater 10 is covered with the heat insulating material 11. For this reason, when using the low melting point alloy which is not a liquid industrial oil at normal temperature and normal pressure (25 ° C., 1 atm) as the pressure transmission medium, it is liquid by heating using the heater 10. Will be pumped.

  Although omitted in FIG. 2, the outer periphery of the first conduit 13 a and the second conduit 18 is actually mounted with a heater 10 over almost the entire length, and the outer periphery of the heater 10 is Since it is covered with the heat insulating material 11, both the pressure transmission medium discharged from the external pressure booster 5 and the pressure medium discharged from the separator 20 can be pumped while maintaining a predetermined temperature and maintaining a liquid state. Has been.

  A method for heating and pressurizing the aluminum casting M as an article as an example will be described below using the apparatus configured as described above.

  First, in a state where the lid 2a and the container 2 are separated from each other, a predetermined amount of molten salt as a heat / pressure transmission medium that is heated in advance into the cavity 3 to be liquid is injected. As the molten salt in this case, a commercially available composite salt having a melting point of 145 ° C. (trade name “Baslick”) manufactured by Sankei Metallurgical Industry Co., Ltd. was used. Next, the container 2 is heated by the heater 10 to increase the temperature of the molten salt injected into the cavity 3, and finally reaches about 520 ° C. which is a temperature necessary for the densification treatment of the aluminum casting M. Let it reach and maintain its temperature. In this state, the aluminum casting M heated to a predetermined temperature (about 520 ° C.) is immersed in the molten salt in the cavity 3. Thereafter, the lid 2a is moved immediately above the container 2 by a transport device (not shown), and then the hydraulic cylinder 6 as a fixing means is operated to push up the container 2, and the upper surface of the lid 2a is The container 2 and the lid 2a are pressed and pressed against the ceiling surface so that the close contact between the lid 2a and the container 2 can be maintained even when the molten salt in the cavity 3 is pressurized. At this time, a very small amount of air is trapped in the air reservoir 8 and is released to the outside by opening a valve (not shown) connected to the outer end of the air passage 9.

  Subsequently, the inside of the flow path 7 formed in the lid 2a, the inside of the first pipe line 13a, and the inside of the pressurized medium storage chamber 22 of the separator 20 are connected to the first pipe line 13a. The molten salt is filled as a pressurized medium by an injection device (not shown). Then, since the pressure transmission medium accommodation chamber 23 formed inside the metal bellows 17 as an isolation member in the medium accommodation chamber 21 is empty, the metal bellows 17 is closed by the injected molten salt. The edge is pushed and shortened to the minimum length. The molten salt has the same components as the heat / pressure transmission medium. Subsequently, the bore 4 of the external pressure booster 5 is filled with hydraulic hydraulic fluid as a pressure transmission medium by an injection device (not shown) connected to the bore 4. The temperature of the heater 10 mounted on the lid 2a in which the flow path 7 is formed, the first pipe line 13a, and the separator 20 is equal to or higher than the melting point of the molten salt as the pressurizing medium. By heating to 180 ° C. in this embodiment, the molten salt in the flow path 7, the first conduit 13 a and the pressurized medium storage chamber 22 is brought into a liquid state.

  Thereafter, the ram 5a of the external pressure booster 5 is caused to enter the hydraulic fluid in the bore 4 by a pressure cylinder (not shown), and a predetermined pressure (about 210 MPa in this embodiment) is applied to the hydraulic fluid. Then, since the hydraulic fluid is already liquid, it is discharged from the pressure transmission medium discharge port 17 formed in the bottom surface of the external pressure booster 5 and passes through the second pipe 18 and the pressure transmission medium introduction port 16. It is pumped into the pressure transfer medium storage chamber 23. For this reason, the metal bellows 17 is pushed by the pressure transfer medium from the inside of the closed end thereof, and is extended by overcoming the pressure of the pressure medium in the pressure medium storage chamber 22. As the volume increases, the volume of the pressurized medium storage chamber 22 decreases. Then, an amount of the pressurized medium corresponding to the volume reduction of the pressurized medium storage chamber 22 is discharged from the pressurized medium discharge port 15 into the first pipeline 13a, and the first pipeline 13a and A predetermined pressure is instantaneously propagated to the molten salt as the heat / heat / pressure transmission medium in the cavity 13 by the pressurized medium filled in the flow path 8, and the predetermined pressure is applied to the aluminum casting M in the cavity 3. Pressure (about 210 MPa) will act. As a result, the aluminum casting M is densified by reducing or eliminating the voids.

  The volume of the bore 4 of the external pressurizer 4 is sufficiently larger than the total volume of the maximum volume of the pressure transmission medium storage chamber 23 (when the metal bellows 17 is extended to the maximum) and the volume of the second pipe 18. Therefore, it is possible to reliably transmit pressure by the pressure transmission medium. In addition, when the pressure of the molten salt in the cavity 3 rises and fills the air reservoir 8 during this pressurization, the molten salt passes from the air passage 9 communicating with the air reservoir 8 to the outside of the container 2. In this case, the leakage of the molten salt is stopped by closing the valve (not shown) connected in communication with the air passage 9.

  In order to keep the molten salt as the pressurizing medium in the flow path 7, the first pipe line 13 a and the pressurizing medium accommodating chamber 22 in a liquid state, the melting as the heat / pressure transmission medium in the cavity 3 is performed. It is not necessary to raise the temperature of the salt, and it is sufficient that the salt is heated to a temperature higher than the melting point of the molten salt. Accordingly, molten salt having a temperature lower than that of the molten salt in the cavity 3 flows from the flow path 7 into the air reservoir 8 during the pressurizing process, but the volume of the air reservoir 8 is extremely small compared to that of the cavity 3. For this reason, the temperature of the molten salt in the cavity 3 hardly decreases and does not affect the heat treatment of the aluminum casting M.

  In the first and second embodiments, the heater 10 mounted on the outer periphery of the container 2 is used to heat the molten salt in the cavity 3, but the heater 10 is installed in the cavity 3. It is also possible to heat the molten salt directly. In this case, the outer periphery of the container 2 is covered with the heat insulating material 11 and the outer periphery of the heater 10 between the heater 10 and the inner wall of the cavity 3 is covered. With such a configuration, it is possible to greatly increase the heating efficiency as compared with the case of heating from the outer periphery of the container 2 as in the first and second embodiments.

  In the first and second embodiments, the molten aluminum as the heat / pressure transmission medium is injected into the cavity 3 and then the aluminum casting M as an article is put into the cavity 3. It is also possible to put the aluminum casting M into the cavity 3 and then inject molten salt as a heat / pressure transmission medium into the cavity 3. In this case, usually, the container 2 is heated in advance, the temperature inside the cavity 3 is raised to a predetermined temperature, and then the heated article is put into the cavity 3, and then the molten material heated to the predetermined temperature is melted. The process proceeds by injecting salt into the cavity 3.

  The above embodiments are for illustrative purposes only, and it will be apparent to those skilled in the art that appropriate modifications and variations can be made to the embodiments. The present invention includes such variations and modifications, and The scope of the present invention should be determined from the appended claims and their equivalents without departing from the technical spirit of the invention.

  Without using a punch (piston), a metal disposable sheet is not required, so the labor and cost of sheet replacement can be reduced. It is possible to reliably transmit the pressure generated by the external pressure booster to the article in the cavity, which is useful industrially.

FIG. 1 is a schematic sectional view of Example 1 of the apparatus of the present invention. FIG. 2 is a schematic sectional view of Embodiment 2 of the apparatus of the present invention.

Claims (27)

By placing an article into the cavity of a container having a cavity into which the article can be sealed, filling the cavity with a liquid heat / pressure transfer medium, and heating and pressurizing the heat / pressure transfer medium In a method of heating and pressurizing an article using a heat / pressure transmission medium,
Pressurization of the heat / pressure transmission medium is performed via a pressure medium that is completely liquefied with the same component as the heat / pressure transmission medium by an external pressure booster connected to the cavity through a pipe line. Method. The method according to claim 1, wherein a melting point of the heat / pressure transmission medium is equal to or lower than a heating temperature of the article. The method according to claim 1, wherein the heat / pressure transmission medium is nitrate or nitrite alone, a mixed salt of nitrate, a mixed salt of nitrite, or a mixed salt of nitrate and nitrite. The heating of the heat / pressure transmission medium in the cavity is performed by a heater provided around the container, and the outer periphery of the heater is covered with a heat insulating material. The method described. The heating of the heat / pressure transmission medium in the cavity is performed by a heater provided in the cavity, and the outer periphery of the heater is covered with a heat insulating material. The method described. 6. The article according to claim 1, wherein the article is a cast or a molded body containing at least one of metal powder or ceramic powder, and the cast or the molded body is heated and pressurized to form a densified cast or sintered body. The method according to any one of the above. Heat and pressure transmission of liquid that includes a cavity and encloses the heat and pressure transmission medium of the article and liquid in the cavity and heats and pressurizes the liquid heat and pressure transmission medium to heat and pressurize the article An apparatus for heating and pressurizing an article using a medium,
A container provided with a lid for sealing or opening the cavity in a detachable manner, the container having a flow path communicating between the cavity and the outside of the container;
A conduit connected in communication with the outer end of the flow path at one end;
An external pressure intensifier which is connected to the other end of the pipe and is separated from the container and contains a pressurized medium therein, and transmits the heat and pressure in the cavity via the pressurized medium An external pressure booster that pressurizes the medium;
A heater for heating the heat / pressure transmission medium and the pressure medium provided in the container, the external pressure intensifier, and the pipe;
Equipment provided. The lid is formed with a conical air pocket whose bottom is the bottom of the lid and the diameter of the bottom circle is equal to the diameter of the cavity. 8. The apparatus according to claim 7, wherein a flow path serving as an end and an air passage having an apex of the air reservoir as an inner end and a side wall of the lid as an outer end are respectively penetrated. A frame surrounding the container;
Fixing means provided between a lower end of the container and an inner bottom surface of the frame, and the fixing means holds the container when the heat / pressure transmission medium in the cavity is pressurized. The apparatus according to claim 7, wherein the apparatus is pushed up to press the upper surface of the lid against the ceiling surface of the frame, and the lid is fixed against a force acting on the lid from the heat / pressure transmission medium. The heater for heating the heat / pressure transmission medium in the cavity is provided around the container, and the outer periphery of the heater is covered with a heat insulating material. The device according to any one of the above. The heater for heating the heat / pressure transmission medium in the cavity is provided in the cavity, and the outer periphery of the heater is covered with a heat insulating material. An apparatus for heating and pressurizing an article using the liquid heat / pressure transmission medium according to one. Liquid heat that fills the cavity with a liquid heat / pressure transfer medium and pressurizes and heats the heat / pressure transfer medium In a method of pressurizing and heating an article using a pressure transmission medium,
The pressurization of the heat / pressure transmission medium is generated by an external pressure booster connected to the cavity via a separator.
The generated pressure is transmitted to the pressure transmission medium accommodated in a pressure medium having the same component as that of the heat / pressure transmission medium in the separator and a pressure transmission medium having a different component.
A method of pressurizing the heat / pressure transmission medium in the cavity through the pressurized medium by transmitting the transmitted pressure to the pressurized medium. The pressure medium and the pressure transmission medium are isolated by a stretchable separation member, and when the pressure transmission medium is press-fitted into the separator, the separation member expands to apply pressure from the pressure transmission medium to the pressure medium. 13. The method of claim 12, wherein is propagated. The method according to claim 12 or 13, wherein a melting point of the heat / pressure transmission medium is equal to or lower than a heating temperature of the article. The method according to any one of claims 12 to 14, wherein the heat / pressure transmission medium is nitrate or nitrite alone, a mixed salt of nitrate, a mixed salt of nitrite, or a mixed salt of nitrate and nitrite. . The method according to any one of claims 12 to 15, wherein the pressure transmission medium is a liquid industrial oil at normal temperature and pressure. The method according to claim 12, wherein the pressure transmission medium is a low melting point alloy. The method according to claim 12, wherein a melting point of the pressure transmission medium is lower than a melting point of the pressure medium. The heating of the heat / pressure transmission medium in the cavity is performed by a heater provided around the container, and the outer periphery of the heater is covered with a heat insulating material. The method described. The heating of the heat / pressure transmission medium in the cavity is performed by a heater provided in the cavity, and the outer periphery of the heater is covered with a heat insulating material. The method described. 21. The article is a molded article including at least one of a casting, a metal powder, or a ceramic powder, and presses and heats the casting or the molded article to form a densified casting or sintered body. The method as described in any one of these. Heat and pressure transmission of liquid that includes a cavity and encloses the article and liquid heat / pressure transmission medium in the cavity and pressurizes and heats the article by pressurizing and heating the heat / pressure transmission medium An apparatus for pressurizing and heating an article using a medium,
A container provided with a lid for sealing or opening the cavity in a detachable manner, the container having a flow path communicating between the cavity and the outside of the container;
A first pipeline connected at one end to the outer end of the flow path;
A medium storage chamber is provided inside, and the medium storage chamber is isolated by a stretchable isolation member into a pressurization medium storage chamber and a pressure transfer medium storage chamber, and the other end of the first conduit, the pressurization medium storage chamber, A separator connected in communication,
A second conduit connected in communication with the pressure transfer medium storage chamber at one end;
An external pressure intensifier connected to the other end of the second pipe and separated from the container and containing the pressure transmission medium therein, and pressurizing the pressure medium via the pressure transmission medium An external pressure booster that propagates through and pressurizes the heat and pressure transfer medium in the cavity;
Provided in the container, the separator, the external pressure booster, the first pipe, and the second pipe;
A pressure transmission medium, a heating medium for heating the pressure medium and the pressure transmission medium,
Equipment provided. The isolation member in the medium storage chamber is a metal bellows whose one end is closed, and an open end side of the metal bellows is brought into close contact with an inner wall of the medium storage chamber, and the pressure transfer medium is passed through the metal bellows. The apparatus according to claim 22, which is a storage chamber. The lid of the container is formed with a conical air pocket whose bottom is the bottom of the lid and whose diameter of the bottom circle is equal to the diameter of the cavity, and the inclination of the air pocket with the side wall of the lid as an external end. 24. The flow path according to claim 22 or 23, wherein a flow path having a surface as an inner end and an air passage having an apex of the air reservoir as an inner end and a side wall of the lid as an outer end are respectively penetrated. apparatus. A frame surrounding the container;
Fixing means provided between a lower end of the container and an inner bottom surface of the frame, and the fixing means holds the container when the heat / pressure transmission medium in the cavity is pressurized. 25. The device according to any one of claims 22 to 24, wherein the lid is pushed up to press the upper surface of the lid against the ceiling surface of the frame, and the lid is fixed against a force acting on the lid from the heat / pressure transmission medium. apparatus. The heater for heating the heat / pressure transmission medium in the cavity is provided around the container, and the outer periphery of the heater is covered with a heat insulating material. Equipment. The apparatus according to any one of claims 22 to 25, wherein a heater for heating the heat / pressure transmission medium in the cavity is installed in the cavity, and an outer periphery of the heater is covered with a heat insulating material. .

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