JP2017035736A - Manufacturing method of capsule for hip and manufacturing method of sintered body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a capsule for HIP hardly causing a tear in HIP treatment time.SOLUTION: In a manufacturing method of a capsule for HIP for integrating a container for HIP and a cover, by welding the cover to an opening part of the container for HIP having the opening part on at least one end side, the cover comprises a plate-like top board part and a sidewall part erected along an inner peripheral surface of the opening part of the container for HIP in its peripheral edge part, and comprises a process of butting an inner peripheral surface 12 of the opening part of the container for HIP and an outer peripheral surface of the sidewall part of the cover and a process of welding the container for HIP and the cover, and in the butting process, the opening part of the container for HIP is set upward, and an upper end surface of the sidewall part of the cover and an upper end surface of the opening part of the container for HIP are deviatively held, and in the welding process, welding is executed while alternately moving a torch 13 in the crossing direction to a boundary along the boundary of a part of butting the container for HIP and the cover.SELECTED DRAWING: Figure 8

Description

The present invention relates to a method for manufacturing a capsule for HIP (Hot Isostatic Pressing).

As one of methods for obtaining a sintered body having a high density, there is a method of performing a treatment under a high temperature and a high pressure called HIP treatment. In a typical HIP process, a HIP capsule obtained by integrating a HIP container and a lid by welding is deaerated by vacuuming from a deaeration hole provided in a normal lid, and then the deaeration hole is formed. A high density sintered body is obtained by closing and then exposing to a high temperature and high pressure atmosphere.

In particular, in order to perform HIP processing from powder, it is necessary to put the powder as a raw material in a HIP container and seal it with a lid so as to maintain airtightness to obtain a capsule for HIP. HIP containers need heat resistance and pressure strength at temperatures required for sintering, and in addition, ductility and malleability are necessary to conduct pressure to the internal raw material powder. Metal is used. After putting the raw material powder into the HIP container, when the HIP container is covered, the lid is joined by welding to ensure sufficient airtightness. In this joining, from the viewpoints of joining strength, welding range, impurity contamination prevention, workability, etc., TIG welding (hereinafter referred to as TIG welding or welding, hereinafter) which is usually non-consumable electrode type arc welding and does not use a welding rod of a different metal. Is often used.

Patent Document 1 that discloses a specific HIP capsule includes a HIP can (corresponding to the HIP capsule) in which a HIP can outer cylinder (corresponding to the HIP container) and an upper lid (corresponding to the lid) are butted and welded. A TIG welding system is disclosed. In Patent Document 1, the position and angle of the torch are selected in the robot control panel according to the deviation amount and direction of the part where the inner peripheral upper end of the HIP can outer cylinder that is the welding part and the outer peripheral upper end of the upper lid are abutted. A method of performing welding is disclosed. The amount of shift of the illustrated butted portion is about 3 mm.

JP-A-8-174218

According to the TIG welding system for HIP cans utilizing the welding robot disclosed in Patent Document 1, the workability and reliability of welding are improved as compared with the conventional technique. However, welding is performed by selecting the position and angle of the torch according to the positional relationship of the part where the inner peripheral upper end of the HIP can outer cylinder and the outer peripheral upper end of the upper lid are abutted. Difficult to make symmetrical. If the welded portion is not symmetrical, the HIP capsule breaks during HIP processing, and the airtight state due to deaeration and sealing is lost (hereinafter, this phenomenon is expressed as “blurring of the HIP capsule”). Sometimes).

Further, according to the inventor's study, in welding the HIP container and the lid, if the output of the torch is too high, the abutted parts are melted as a whole, and it is difficult to weld appropriately. Become. On the other hand, when a low-power torch is used, the melting is insufficient, the cross-sectional shape of the welded portion changes, and the adhesion of the welded portion of the HIP capsule is affected. In particular, the rectangular cylindrical HIP container is more likely to be biased in the distribution of the pressure applied by the HIP process as compared to the cylindrical HIP container. The bias of the applied pressure increases the stress applied to the welded portion, and thus the HIP capsule tends to be shaken during the HIP process.

An object of the present invention is to provide a method for producing a capsule for HIP that is to solve the above-described problems and is less likely to be shaken during HIP processing.

The first HIP capsule manufacturing method of the present invention is a HIP capsule having an opening on at least one end side, wherein a lid is welded to the opening, and the HIP container and the lid are integrated. In the manufacturing method, the lid has a plate-like lid plate portion and a side wall portion standing on the peripheral portion thereof along the inner peripheral surface of the opening portion of the HIP container, and the opening of the HIP container A step of abutting the inner peripheral surface of the portion with the outer peripheral surface of the side wall portion of the lid, and a step of welding the HIP container and the lid, wherein the opening portion of the HIP container is directed upward The upper end surface of the side wall portion of the lid and the upper end surface of the opening portion of the HIP container are shifted and held, and in the welding step, the boundary between the inner peripheral surface of the HIP container and the outer peripheral surface of the lid And with respect to the boundary Characterized by welding while alternately moving the torch in the direction of the difference.

In the first method of the present invention, it is preferable that an amount of shifting the upper end surface of the opening portion of the HIP container and the upper end surface of the side wall portion of the lid in the abutting step is 0.5 mm to 2 mm.

As a second method for producing a capsule for HIP of the present invention, a HIP container having an opening on at least one end thereof, a lid is TIG welded to the opening, and the HIP container and the lid are integrated. In the capsule manufacturing method, the lid has a plate-like lid plate portion, a side wall portion, and a bent portion, and the side wall portion stands on the peripheral edge portion of the lid plate portion along the inner peripheral surface of the opening portion. The bent portion protrudes in the outer peripheral direction so as to contact the upper end surface of the opening at the upper end of the side wall, and the inner peripheral surface of the opening of the HIP container and the side wall of the lid A step of abutting the outer peripheral surface of the part, and a step of welding the HIP container and the lid, and in the abutting step, the bent portion of the lid is brought into contact with the upper end surface of the opening of the HIP container Holding and welding, Along the boundary of matching the inner and outer circumferential surfaces of the lid of the IP container, and characterized in that welding while moving the torch alternately in a direction intersecting the boundary.

In the second method of the present invention, the thickness of the bent portion of the lid is 0.5 mm to 1.5 mm, and the outer peripheral surface of the bent portion of the lid is the upper end surface of the opening of the HIP container. It is preferable not to protrude beyond.

According to the method of the present invention, the HIP container and the lid can be firmly welded, and a symmetrical welded portion can be formed across these two members. Therefore, by using the capsule for HIP, blurring hardly occurs during HIP processing.

It is a perspective view showing roughly a container for HIP and a lid concerning a method of a 1st embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view of a YZ plane passing through a one-dot chain line AA in FIG. 1 as viewed from the X direction, showing a state before the HIP container and the lid shown in FIG. It is the top view which expanded and showed the state immediately after butting | matching the inner peripheral surface of the container for HIP shown in FIG. 1, and the outer peripheral surface of a lid | cover. FIG. 4 is a cross-sectional view of the YZ plane passing through the alternate long and short dash line AA in FIG. 3 when viewed from the X direction when the end surface 4a of the lid is high when the HIP container and the lid are butted. FIG. 4 is a cross-sectional view of the YZ plane passing through the alternate long and short dash line AA in FIG. 3 when viewed from the X direction when the end surface 3 of the HIP container is high when the HIP container and the lid are butted. It is a top view which shows the welding part of the boundary which faced the container for HIP, and a lid | cover, and shows schematically how to move the torch during welding. FIG. 7 is a side view schematically showing how to move the torch during welding when FIG. 6 is viewed from the Y direction. FIG. 8 is a cross-sectional view of the YZ plane passing through the alternate long and short dash line AA shown in FIGS. 6 and 7 when viewed from the X direction. It is a perspective view which shows roughly the container for HIP and a lid | cover based on the method of the 2nd Embodiment of this invention. FIG. 10 is an enlarged cross-sectional view of a YZ plane passing through the one-dot chain line AA of FIG. 1 as viewed from the X direction, showing a state before the HIP container and the lid shown in FIG. It is the top view which expanded and showed the state after matching the container for HIP shown in FIG. 9, and a lid | cover. It is sectional drawing which looked at the YZ plane which passes along the dashed-dotted line AA of FIG. 11 from the X direction. FIG. 13 is a top view schematically showing how to move the torch while welding the end surfaces of the HIP container and the lid shown in FIGS. 11 and 12. In the welding method of this invention, it is a top view of the welding part which shows the state after welding the container for HIP, and a lid | cover. It is sectional drawing which looked at the YZ surface which passes along the dashed-dotted line AA of FIG. 14 from the X direction. In Comparative Example 2, it is a top view schematically showing how to move the torch while welding the HIP container and the lid.

Embodiments of the present invention will be described below in detail with reference to the drawings, but the present invention is not limited thereto. The description of each embodiment is applicable to other embodiments unless otherwise specified.

[1] First Embodiment FIGS. 1 and 2 show a HIP container 1 and a lid 2a according to a first embodiment of the present invention. In the figure, a case where a rectangular cylindrical HIP container and a rectangular plate-like lid are used is shown. FIG. 1 is a perspective view schematically showing a HIP container 1 having an opening 5 on one end side and a lid 2a having a shape corresponding to the opening. FIG. 2 is a partially enlarged cross-sectional view of the YZ plane passing through the alternate long and short dash line AA of FIG. 1 as a representative example of the location where the welding method of the present invention is described. In particular, the vicinity of the end surface 3 of the container for welding the HIP container and the lid and the end surface 4a of the lid is shown in an enlarged manner, and other portions are omitted by wavy lines. Also in the following drawings, the wavy line portion is omitted, and the cross-sectional view shows a partial cross section when the YZ plane passing through the alternate long and short dash line AA is viewed from the X direction.

The lid 2a of the HIP container has a plate-like lid plate portion 6 and a side wall portion 7a standing on the peripheral portion thereof along the inner peripheral surface 10 of the opening of the HIP container. The side wall portion 7a and the lid plate portion 6 are orthogonal to each other, with the side wall portion 7a facing upward, and similarly with the opening 5 of the HIP container facing upward, the outer peripheral surface 9a of the side wall portion 7a and the The inner peripheral surface 10 of the opening 5 is parallel. In the figure, 8 indicates a deaeration tube.

As the material of the HIP container 1 and the lid 2a, iron, stainless steel or the like that can be welded can be used. The thickness t1 of the HIP container 1 and the thickness t2 of the lid 2a can be selected according to the strength of the material, and it is preferably 1 to 2 mm for iron. Further, the thickness t3a of the side wall 7a is preferably the same as the thickness t1 in order to make the heat dispersion during welding the same as that of the HIP container 1.

After filling the HIP container 1 with the raw material powder without any gaps, the HIP container with the opening 5 facing upward is brought into contact with and held with a lid with the side wall portion 7a facing upward. The top view of FIG. 3 and the cross-sectional view of FIG. At this time, the upper end surface of the HIP container 1 facing upward is simply referred to as an end surface 3, and the upper end surface of the lid 2a is referred to as an end surface 4a. As shown in FIGS. 3 and 4, the outer peripheral surface 9a of the side wall portion 7a of the lid 2a and the inner peripheral surface 10 of the HIP container 1 are abutted, and the end surface 3 and the end surface 4a located above each are shifted. Hold. FIG. 4 shows a cross section taken along one-dot chain line AA in FIG. The height difference Ha between the shifted end faces is preferably 0.5 to 2 mm. If it is the range of the said height difference Ha, the height of the welding part close | similar to the thickness of the container for HIP will be obtained after welding, and the time taken to fuse | melt will also be short. As long as the height difference Ha is secured, either the end face 3 or the end face 4a may be high. Specifically, the same effect can be obtained not only when the end face 3 is higher as shown in the cross-sectional view of FIG. 4 but also when the end face 4a is higher as shown in the cross-sectional view of FIG.

As shown in FIG. 4, welding is advanced along a boundary 12 where the outer peripheral surface 9 a and the inner peripheral surface 10 are abutted. FIG. 6 is a top view, FIG. 7 is a side view, and FIG. 8 is a cross-sectional view schematically illustrating how the torch is moved during welding in the first embodiment. A torch 13 and an arc 14 for welding are schematically shown in the figure. Since welding is in progress, in FIG. 6, the boundary 12 before welding is indicated by a solid line, and the boundary 12 after welding is hidden under the weld portion 18, and thus is indicated by a broken line. FIG. 8 shows a cross-sectional view of the YZ plane passing through the one-dot chain line AA of FIGS. 6 and 7 when viewed from the X direction. The welded portion 18 after welding in the X direction from the boundary just below the torch being welded in FIG. 8 is indicated by a solid line, and the end surface 3 and the end surface 4a before welding in the −X direction are The hidden part is indicated by a dotted line, and the visible part is indicated by a solid line.

The torch 13 is preferably applied perpendicularly to the end surface 3 and the end surface 4a, but may be inclined in consideration of workability. The output of the torch 13 is set so that the end surface 3 and the end surface 4a can be melted and maintained without flowing out of the range between the outer peripheral edge 15 of the end surface 3 and the inner peripheral edge 16a of the end surface 4a. Since the end surface 3 and the end surface 4a are shifted and held, the end surface 4a close to the torch 13 is preferentially melted, and the end surface 3 is melted to a depth necessary for welding with the melted portion of the end surface 4a and fused together. After that, the weld 18 is formed.

While the torch 13 is moved alternately in the direction intersecting the boundary 12 within the range of the outer peripheral edge 15 of the end face 3 and the inner peripheral edge 16a of the end face 4a, the boundary between the HIP container 1 and the lid 2a 12 and go around. In FIGS. 6 and 8, the trajectory 17 of the torch that is welded while being moved is indicated by an arrow, and welding is performed while being moved alternately around the boundary 12 in the range from the edge 15 to the edge 16a.

The HIP container 1 is sealed with a lid 2a and welded to obtain a HIP capsule. The HIP capsule is hermetically sealed by degassing the degassing tube 8 of the HIP capsule using a vacuum pump and sealing the degassing tube 8. After sealing the HIP capsule, HIP treatment is performed to obtain a sintered body.

In the above description, the case where the rectangular cylindrical HIP container 1 and the rectangular plate-shaped lid 2a are used has been described. However, the same effect can be obtained even when the cylindrical HIP container and the disk-shaped lid are used. It is done. Moreover, although the case where the opening 5 of the HIP container is also provided at one end side has been described, a lid is welded to each opening 5 by the same method as described above even when provided at both ends. Can do. Furthermore, although the case where one deaeration tube 8 is provided at the center of the upper surface of the lid is illustrated, the number and arrangement location thereof can be appropriately selected according to the filling amount of the raw material powder and the like.

In the method of the first embodiment of the present invention, when the HIP container 1 and the lid 2a are brought into contact with each other, the heat of the torch is concentrated on the end surface that is high when welding by shifting the upper end surfaces of the containers. However, the temperature tends to rise. Therefore, the melting depth from the increased end surface can be made deeper than when the end surface 3 of the HIP container 1 and the end surface 4a of the lid 2a have the same height. If a different metal welding rod is used, the weld strength can be increased by increasing the welded portion. However, since there is a possibility that foreign metal is mixed in the raw material inside the capsule for HIP, a different metal welding rod is generally used. Is not used. However, according to the method of the present invention, the raised end can be used as a welded portion, and even if a welding rod is not used, the effect of using a welding rod of the same kind of metal is obtained, and the welding strength is improved.

By welding while moving alternately in the range from the edge 15 to the edge 16a around the boundary 12, the welded portion 18 can be symmetric. The effect of improving the welding strength and the effect of making the welded portion symmetric can be obtained by preventing the molten portion from flowing out of the range.

[2] Second Embodiment In the second embodiment of the present invention, a lid 2b is used instead of the lid 2a used in the first embodiment as shown in FIGS. The lid 2 b has a plate-like lid plate portion 6, a side wall portion 7 b, and a bent portion 19, and the side wall portion 7 b is arranged along the inner peripheral surface 10 of the opening 5 at the peripheral edge portion of the lid plate portion 6. The bent portion 19 protrudes in the outer peripheral direction at the upper end portion in the Z direction of the side wall portion 7b so as to contact the upper end surface in the Z direction of the opening portion 5. Similar to the first embodiment, the side wall portion 7b is used upward, and the upper end surface facing upward is defined as an end surface 4b.

FIG. 10 is a partially enlarged cross-sectional view of the YZ plane passing through the alternate long and short dash line AA when the HIP container 1 of FIG. 1 and the lid 2b of FIG. 9 are used. When the outer peripheral surface 9b of the lid 2b and the inner peripheral surface 10 of the HIP container 1 are brought into contact with each other using the lid 2b having the bent portion 19, the lower surface 23 of the bent portion 19 contacts the end surface 3. The protruding amount L of the bent portion 19 is smaller than the thickness t 1 of the HIP container 1, and the outer peripheral surface 22 of the bent portion 19 is inward of the edge 15 on the outer peripheral side of the end surface 3 when the lid 2 b is abutted against the HIP container 1. Located on the circumferential side. If the outer peripheral surface 22 exceeds the edge 15 on the outer peripheral side of the end surface 3 of the HIP container, it is not preferable because the molten part flows out to the outer peripheral side of the HIP container 1 during welding. The configuration of the lid 2b other than the bent portion 19 is the same as that of the lid 2a of the HIP container used in the first embodiment, and includes a lid plate portion 6 and a side wall portion 7b. The thickness t2 of the lid 2b can be selected according to the strength of the material as in the first embodiment, and is preferably 1 to 2 mm for iron. Also, the thickness t3b of the side wall portion 7b is preferably the same as the thickness t1 as in the first embodiment.

After filling the HIP container 1 with the raw material powder without any gap, the inner peripheral surface 10 of the HIP container 1 and the outer peripheral surface 9b of the side wall portion 7b are brought into contact with each other. At this time, the lower surface 23 of the bent portion 19 comes into contact with the end surface 3, and the state shown in FIGS. 11 shows a top view of the HIP container 1 and the lid 2b before welding, and FIG. 12 shows a cross-sectional view of the YZ plane passing through the alternate long and short dash line AA from the X direction. When viewed from the top view, the bent portion 19 protrudes from the side wall portion 7b by a protruding amount L, and covers the boundary 12 and part of the end surface 3. Since the boundary 12 is located below the bent portion 19, it is shown by a dotted line.

The height difference Hb between the end surface 3 and the end surface 4 b is determined by the thickness of the bent portion 19. The height difference Hb when the bent portion 19 is provided is preferably 0.5 to 1.5 mm. The preferable upper limit is smaller than the height difference Ha between the end surface 3 and the end surface 4a in the first embodiment. In the lid 2b of the second embodiment, the bent portion 19 is also used as a melting portion for welding. This is because it is easier to obtain more melting portions than in the first embodiment.

In a state where the HIP container 1 and the HIP container lid 2b are brought into contact with each other, welding is advanced along a line extending the boundary 12 between the inner peripheral surface 10 of the opening 5 and the outer peripheral surface 9b of the side wall 7b in the Z direction. . FIG. 13 shows a top view during welding in the second embodiment. Similar to the first embodiment, the angle of the torch 13 and the output conditions are set at an angle close to perpendicular to the end face 3 and the end face 4b in consideration of workability. When the lid 2b is used, the bent portion 19 is preferentially melted and welded to the lower end surface 3 thereof. When welding around the boundary 12 between the HIP container 1 and the lid 2b, welding is performed while moving from the edge 15 to the edge 16b alternately in the direction intersecting the boundary 12 as in the first embodiment. . Therefore, the torch trajectory 17 viewed from above is a meandering trajectory as in the first embodiment. By the said movement, the uniform welding part 18 is obtained similarly to 1st Embodiment, and sufficient welding strength which does not generate | occur | produce blurring at the time of HIP processing is exhibited.

Also in the second embodiment, as in the first embodiment, the shape of the HIP container and lid, the number and arrangement of openings, the number and arrangement of deaeration tubes, and the like can be arbitrarily selected.

Also in the method of the second embodiment of the present invention, in order to move the torch 13 from the edge 15 to the edge 16b, heat is applied to both the end surface 3 of the HIP container 1 and the end surface 4b of the lid 2b, while the end surface 4b is applied to the end surface 4b. Concentrated and given heat. Thereby, the raised end face 4b is preferentially melted similarly to the method of the first embodiment, and the bent portion 19 can be used as a melted portion for welding, and the weld strength is improved and the welded portion is symmetrical. The effect to do. Further, when the HIP container 1 and the lid 2b are brought into contact with each other, the bent portion 19 acts as a stopper by bringing the bent portion 19 of the lid 2b into contact with the end surface 3 of the HIP container 1. In the method of the first embodiment, each end face is shifted and the clip or the deaeration tube is held by a stand or the like, whereas the bent portion acts as a stopper and can be easily held. become.

The protruding amount L of the bent portion 19 acts so as not to allow the molten portion to flow out of the range by not exceeding the outer peripheral surface 10 of the HIP container. As in the first embodiment, the effect of improving the welding strength and the effect of making the welded portion symmetrical are obtainable by preventing the molten portion from flowing out of the range.

Example 1 Capsules for HIP were produced using the method of the first embodiment. The HIP container 1 has a cylindrical shape having an opening at one end and a rectangular cross section, and a lid 2 a having an outer peripheral shape corresponding to the inner peripheral surface of the opening 5 of the HIP container 1. The HIP container thickness t1, the lid plate portion 6 thickness t2, and the side wall portion 7a had a thickness t3a of 1.8 mm. After filling the raw material powder into the HIP container, the HIP container 1 and the lid 2a were butted together. The height difference Ha between the end face 3 and the end face 4a was kept at 0.7 mm. TIG welding was used for welding the HIP container 1 and the lid 2a, and welding was performed while the torch 13 was alternately moved in the direction intersecting the boundary 12. The HIP container 1 and the lid 2a were made of iron, and no welding rods of different metals were used during welding.

14 and 15 are a top view and a cross-sectional view schematically showing the welded portion 18 after the HIP container and the lid are welded. FIG. 15 is a cross-sectional view of the YZ plane passing through the one-dot chain line AA in FIG. 14 as viewed from the X direction. Actually, the welded portion was cut and polished to make the boundary 12 easier to see, and then observed using a measuring microscope, and the dimension h from the top of the welded portion to the intersection of the welded portion and the boundary 12 was measured. As a result, the cross-sectional shape of the welded portion 18 was symmetrical with respect to the boundary 12, and the dimension h was 1.7 mm.

The capsule for HIP produced in Example 1 was used to deaerate from the deaeration tube 8 using a vacuum pump, and the deaeration tube 8 was heated with a burner and crushed with a press machine to be sealed. Thereafter, the HIP capsule was subjected to HIP treatment. No blurring occurred during the HIP process, and the obtained sintered body was a high-density sintered body containing no impurities of different metals other than iron. The same results were obtained with capsules for HIP manufactured using the same method for manufacturing capsules for HIP as in Example 1 with a height difference Ha of 0.5 mm or 2 mm.

Example 2 A capsule for HIP was produced using the method of the second embodiment. The HIP container 1 is the same as that of the first embodiment, and the lid 2b is an outer peripheral lid plate portion 6 corresponding to the inner peripheral surface of the opening 5 of the HIP container, and has a bent portion 19 on the side wall portion 7b. A thing was used. The projecting amount L of the bent portion 19 was 1.5 mm. A thickness t1 of the HIP container, a thickness t2 of the lid plate portion 6 of the lid 2b, and a thickness t3b of the side wall portion 7b were each 1.8 mm. The end surface 3 and the lower surface 23 of the bent portion 19 were brought into contact with each other, and the height difference Hb between the end surface 3 and the end surface 4b was maintained at a thickness of the bent portion 19 of 1.4 mm. TIG welding under the same conditions as in Example 1 was used for welding the HIP container 1 and the lid 2b, and welding was performed while the torch 13 was alternately moved in the direction intersecting the boundary 12.

The cross section was observed and the dimension h was measured by the same method as described in Example 1. As a result, the cross-sectional shape of the welded portion 18 was symmetrical with respect to the boundary 12, and the dimension h was 1.7 mm.

The capsule for HIP produced in Example 2 was deaerated and sealed under the same conditions as in Example 1 and then subjected to HIP treatment. No blurring occurred during the HIP process, and the obtained sintered body was a high-density sintered body containing no impurities of different metals other than iron. The same results were obtained with capsules for HIP manufactured using the same method for manufacturing capsules for HIP as in Example 2 with a height difference Hb of 0.5 mm or 1.5 mm.

Example 3 A capsule for HIP was produced using the method of the second embodiment. The HIP container 1 has a cylindrical shape with openings at both ends and has a rectangular cross section, and the lid 2b of the HIP container has the same shape as the opening 5 of the HIP container and is bent to the side wall 7b. What has the part 19 was used. The same thickness t1 of the HIP container, the thickness t2 of the lid plate portion 6 of the lid 2b, and the thickness t3b of the side wall portion 7b were used. The protrusion L of the bent portion 19 was 1.8 mm. A lid 2b having an outer peripheral surface 9b that faces one inner opening 5 of the HIP container 1 and abuts the inner peripheral surface 10 of the opening was also prepared with the side wall 7b facing upward. With the HIP container 1 and the lid 2b prepared, the end surface 3 of the HIP container 1 and the lower surface 23 of the bent portion 19 of the lid 2b are brought into contact with each other, and the difference in height between the end surface 3 and the end surface 4b Hb Was held at 1.2 mm. The outer peripheral surface 22 of the bent portion 19 was at the same position as the outer peripheral surface of the HIP container, and there was no protrusion. TIG welding under the same conditions as in Example 1 was used for welding the HIP container 1 and the lid 2b, and welding was performed while the torch 13 was alternately moved in the direction intersecting the boundary 12.

The cross section was observed and the dimension h was measured by the same method as described in Example 1. As a result, the cross-sectional shape of the welded portion 18 was symmetrical with respect to the boundary 12, and the dimension h was 1.7 mm.

The other opening in Example 3 was also welded in the same manner, and the produced HIP capsule was degassed and sealed under the same conditions as in Example 1 and then subjected to HIP treatment. No blurring occurred during the HIP process, and the obtained sintered body was a high-density sintered body containing no impurities of different metals other than iron. The same results were obtained with HIP capsules manufactured with the same HIP capsule manufacturing method under the condition that the height difference Hb was 0.5 mm or 1.5 mm.

Comparative Example 1 The same HIP container 1 and lid 2a as in Example 1 were used. The height difference Ha between the end face 3 and the end face 4a was kept at 0 mm. TIG welding under the same conditions as in Example 1 was used for welding the HIP container 1 and the lid 2a, and welding was performed while the torch 13 was alternately moved in the direction intersecting the boundary 12.

In the same manner as described in Example 1, the cross section of the welded portion was observed and the dimension h was measured. As a result, the shape of the cross section of the welded portion 18 was symmetrical with respect to the boundary 12, but the dimension h was 1.1mm, which was lower than that of Example 1.

The capsule for HIP produced in Comparative Example 1 was deaerated and sealed under the same conditions as in Example 1 and then subjected to HIP treatment. In some cases, blurring occurred after the HIP treatment, and a high-density sintered body could not be obtained from the capsule for HIP in which the blur occurred.

Comparative Example 2 The same HIP container 1 and lid 2a as in Example 1 were used. The height difference Ha between the end face 3 and the end face 4a was kept at 0.6 mm. TIG welding under the same conditions as in Example 1 was used for welding the HIP container 1 and the lid 2a, but the torch 13 was not moved alternately in the direction intersecting the boundary 12 as shown in FIG. The trajectory 17 of the torch drawn a straight trajectory along the boundary 12, and the weld 18 was formed only near the boundary 12.

The capsule for HIP produced in Comparative Example 2 was deaerated and sealed under the same conditions as in Example 1 and then subjected to HIP treatment. In some cases, blurring occurred after the HIP treatment, and a high-density sintered body could not be obtained from the capsule for HIP in which the blur occurred.

The method of the present invention having the above characteristics is suitable for producing a sintered body from a raw material powder by HIP treatment.

DESCRIPTION OF SYMBOLS 1 ... HIP container 2a, 2b ... HIP container lid 3 ... HIP container end surface 4a ... Lid 2a end surface 4b ... Lid 2b end surface 5 ... HIP container Opening part 6 ... Lid plate part 7a ... Side wall part 7b of lid 2a ... Side wall part 8 of lid 2b ... Deaeration tube 9a ... Outer peripheral surface 9b of side wall part 7a ... Side wall part 7b outer peripheral surface 10 ... the inner peripheral surface 12 of the opening portion ... the boundary 13 where the inner peripheral surface 10 of the opening portion and the outer peripheral surface 9a or 9b of the side wall face each other ... the torch 14 ... the arc 15. .... Edge 16a on the outer peripheral side of the end face 3 ... Edge 16b on the inner peripheral side of the end face 4a of the lid ... Edge 17 on the inner peripheral side of the end face 4b of the lid ... Trace 18 of the torch ... 19 ... Lid part 22 of the lid ... Outer peripheral surface 23 of the bend part ... Bottom surface of the bend part

Claims (6)

In a method for manufacturing a capsule for HIP, in which a lid is welded to the opening, and the HIP container and the lid are integrated, the container for HIP having an opening on at least one end side.
The lid has a plate-like lid plate portion and a side wall portion standing on the peripheral portion thereof so as to be along the inner peripheral surface of the opening of the HIP container,
A process of abutting the inner peripheral surface of the opening of the HIP container and the outer peripheral surface of the side wall of the lid;
Welding the HIP container and lid,
In the abutting step, the opening of the HIP container is turned upward, the upper end surface of the side wall of the lid is shifted from the upper end surface of the opening of the HIP container, and the opening of the HIP container is The amount of shifting the upper end surface and the upper end surface of the side wall of the lid is 0.5 mm to 2 mm,
In the welding step, welding is performed while alternately moving the torch along a boundary where the inner peripheral surface of the HIP container and the outer peripheral surface of the lid are abutted and in a direction intersecting the boundary. The manufacturing method of the capsule for HIP.   The method for manufacturing a capsule for HIP according to claim 1, wherein the HIP container and the lid are formed of the same kind of metal material.   The method for manufacturing a capsule for HIP according to claim 2, wherein the HIP container and the lid are made of iron or stainless steel. A method for producing a sintered body in which raw material powder is provided in an HIP container having an opening on at least one end side, the HIP container and the lid are integrated, and HIP processing is performed.
The lid has a plate-like lid plate portion and a side wall portion standing on the peripheral portion thereof along the inner peripheral surface of the opening of the HIP container, and the plate-like lid plate portion has a deaeration pipe Have
A step of abutting an inner peripheral surface of the opening of the HIP container and an outer peripheral surface of the side wall of the lid; a step of welding the HIP container and the lid; and deaeration from the deaeration tube; Having a step of sealing
In the abutting step, the lid is abutted against the HIP container having the raw material powder filled without gaps with the opening of the HIP container facing upward, and the upper end surface of the side wall of the lid and the HIP container The amount of shifting the upper end surface of the opening of the HIP container and the upper end surface of the side wall of the lid is 0.5 mm to 2 mm.
In the welding step, welding is performed while alternately moving the torch along a boundary where the inner peripheral surface of the HIP container and the outer peripheral surface of the lid are abutted and in a direction intersecting the boundary. A method for producing a sintered body.   The method for manufacturing a sintered body according to claim 4, wherein the HIP container and the lid are formed of the same kind of metal material. The method for manufacturing a sintered body according to claim 5, wherein the HIP container and the lid are formed of iron or stainless steel.

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