JP5868598B2 - Turbocharger parts and method of manufacturing turbocharger parts - Google Patents

Description

  The present invention relates to a turbocharger component for an internal combustion engine, and more particularly to improvement of high-temperature wear resistance of the turbocharger component.

In recent years, from the viewpoint of global environmental conservation, there has been a strong demand for improving the fuel efficiency of automobiles, and exhaust gas regulations have been strengthened. Under such circumstances, a turbocharger that has a great effect on improving the fuel consumption of the engine is an essential device for an internal combustion engine (engine).
The turbocharger has a role of supplying high-pressure air to the engine by using the exhaust gas of the internal combustion engine (engine), rotating the turbine, driving a compressor provided coaxially with the turbine. Recently, as such a turbocharger, a variable capacity turbocharger capable of controlling a supercharging pressure has been widely used. In such a turbocharger, a plurality of nozzle vanes are provided along the outside of the turbine, and a nozzle hole for supplying exhaust gas toward the turbine is formed between two nozzle vanes adjacent to each other. And by rotating each nozzle vane, the opening degree of a nozzle hole is changed and the flow volume of the exhaust gas to a turbine is changed. Such a variable capacity turbocharger is said to adjust the supercharging pressure optimally according to the operating conditions of the engine, and to bring about effects such as improvement of low-speed torque, exhaust gas purification, and fuel efficiency improvement.

  Generally, as shown in FIG. 14, the variable turbocharger 10 has a structure in which a turbine 20 and a compressor 30 are attached to both ends of a turbine rotor 41 that is rotatably supported by bearings 40. The turbine 20 includes a turbine wheel 21 attached to one end of the turbine rotor 41, a turbine casing 22 provided so as to surround and cover the turbine wheel 21, and a variable that changes the flow rate of exhaust gas flowing into the turbine wheel 21. And a nozzle mechanism 23. The compressor 30 includes a compressor wheel 31 attached to the other end of the turbine rotor 41 and a compressor casing 32 provided so as to surround and cover the compressor wheel 31. The compressor wheel 31 is rotationally driven by the rotation of the turbine wheel 21 and pumps fluid such as air to the engine.

Recently, with the demand for environmental and fuel efficiency further NO _X reduction of automobiles, variable turbocharger reliability and further improvement in durability has been demanded strongly. For this reason, improvement of the high temperature wear resistance of the turbocharger parts which are driven especially in a high temperature gas environment and under an exhaust pulse or engine vibration is desired.
In response to such a demand, for example, Patent Document 1 proposes that a movable part supporting part for a supercharger, in which wear and corrosion at high temperatures are a problem, is manufactured from a Co-based alloy such as Trivalloy. Yes. In the technique described in Patent Document 1, a Co-based alloy powder such as Trivalloy is injection-molded and then sintered to form a sintered body, which is a movable part supporting part for a supercharger having a thin part. The supercharger movable part support component described in Patent Document 1 is a shaft holder that supports a support shaft of a drive lever that drives a movable device that opens and closes an exhaust vane blade of a supercharger. If manufactured by the kneading method, it has a high degree of freedom in shape and can be manufactured at low cost.

JP 2006-265590 A

In recent years, demands for further improvement of high-temperature wear resistance of sliding parts and moving parts of turbocharger parts at low cost, especially without extreme increase in manufacturing cost, due to severe use conditions. Has been.
However, since the parts obtained by the technique described in Patent Document 1 are manufactured using expensive Co-based alloy powder as a whole, there is a problem that they are expensive.

  An object of the present invention is to solve the above-described problems of the prior art, and to provide a turbocharger part that is inexpensive and excellent in high-temperature wear resistance of sliding parts and movable parts.

  In order to achieve the above-mentioned object, the present inventors diligently studied various factors that contribute to improving the high-temperature wear resistance of turbocharger parts. As a result, it has been thought that a sliding member made of a material excellent in high-temperature wear resistance should be integrally joined or fitted to the surfaces of the sliding part and the movable part. Furthermore, it has been found that by forming the sliding member into a predetermined shape using injection molding or compaction molding, it is possible to obtain a member with high dimensional accuracy and at a low cost.

The present invention has been completed based on the above findings and further studies. That is, the gist of the present invention is as follows .

(1) A turbocharger part having a sliding part and / or a movable part, the surface of the sliding part and / or the movable part being made by injection molding or compacting , and having a hardness of HRC55 to 65 a turbocharger parts sliding member is an alloy steel sintered body having a high-temperature wear resistance, characterized by comprising been integrally morning brazing.

( 2 ) In ( 1 ), the turbocharger part is any one of austenitic stainless steel, high chrome cast iron, gray cast iron, and ductile cast iron, and the sliding member is made of a Co-base alloy. Turbocharger parts characterized by being a united body .

( 3 ) In manufacturing a turbocharger part by joining or fitting a sliding member to the sliding part and / or the movable part of a turbocharger part having a sliding part and / or a movable part, A sliding member that is an alloy sintered body that is molded by injection molding or compacting, has a hardness of HRC 55 to 65, and has high-temperature wear resistance, and the outer surface of the sliding member, or further After processing the surface of the sliding part and the movable part so that the sliding member can be joined or fitted to the surface of the sliding part and / or the movable part, the sliding member is A method of manufacturing a turbocharger part, wherein the turbocharger part is integrally joined or fitted to a surface of a movable part.

( 4 ) In ( 3 ), the turbocharger part is any one of austenitic stainless steel, high chromium cast iron, gray cast iron, and ductile cast iron, and the alloy having the high temperature wear resistance is A method of manufacturing a turbocharger part, wherein the turbocharger part is a Co-based alloy.
( 5 ) The method of manufacturing a turbocharger part according to ( 3 ) or ( 4 ), wherein the joining is brazing.

( 6 ) The method of manufacturing a turbocharger part according to ( 5 ), wherein the brazing material used in the brazing is a brazing material having a liquidus temperature in the range of 800 to 1150 ° C.

  ADVANTAGE OF THE INVENTION According to this invention, the turbocharger components excellent in high temperature abrasion resistance especially the high temperature abrasion resistance of a sliding part and a movable part can be provided at low cost, and there exists a remarkable effect on industry. In addition, according to the present invention, the reliability of the turbocharger is remarkably improved, and it is possible to reduce the thickness of parts, thereby contributing to the weight reduction of the vehicle body. In addition, the present invention has an effect that it can be applied to products in the field of the aerospace industry that strongly requires heat resistance and wear resistance.

It is explanatory drawing which shows typically the outline of the variable nozzle mechanism using the turbocharger components of this invention. It is explanatory drawing which shows typically the operation condition of a variable nozzle mechanism. It is explanatory drawing which shows typically an example of the turbocharger components which become this invention. (A) It is explanatory drawing which shows typically an example of the preferable shape of a sliding member, and the condition which (b) the sliding member joined to the drive groove of the unison ring. It is explanatory drawing which shows typically the example of the preferable shape ((a)-(c)) of a sliding member, and the joining condition of these sliding members and a unison ring. It is explanatory drawing which shows typically the preferable welding location in joining of the sliding member shown in FIG. 4, and a unison ring. It is explanatory drawing which shows typically the preferable welding location in joining of the sliding member and unison ring shown in FIG. It is explanatory drawing which shows typically an example of the preferable shape of a preferable sliding member and / or a unison ring sliding part and a movable part in brazing joining of a sliding member and an unison ring. It is sectional drawing which shows typically another example of the preferable shape of a preferable sliding member and / or a unison ring sliding part and a movable part in brazing joining of a sliding member and an unison ring. It is (a) sectional drawing and (b) perspective view which show an example of an internal crank and an example of the structure of the actuator attachment part vicinity which is a drive mechanism. It is explanatory drawing which shows typically the outline of the high temperature valve seat abrasion tester implemented in the Example. It is a graph which shows typically change of the amount of wear in the high temperature wear test done in the example. It is explanatory drawing which shows typically the mounting state of the test piece in the single-piece | unit fatigue test done in the Example. It is a schematic sectional drawing which shows typically the general structure of a variable turbocharger.

The variable turbocharger 10 generally has a structure in which a variable turbine 20 and a compressor 30 are attached to both ends of a turbine rotor 41 that is rotatably supported by bearings 40. In particular, the variable nozzle mechanism 23 that changes the flow rate of the exhaust gas flowing into the turbine wheel 21 has a large number of sliding parts and movable parts.
As shown in FIG. 1, the variable nozzle mechanism 23 in the variable turbine 20 usually has the following structure.

  A plurality of nozzle vanes 11 arranged at equal intervals in the circumferential direction, a pair of ring-shaped nozzle rings 12 and 12 that rotatably support the nozzle vanes 11, and a ring shape for rotating the nozzle vanes 11. The unison ring 13, the plurality of vane arms 14 that rotate the nozzle vanes 11 in accordance with the rotation of the unison ring 13, and the pair of nozzle rings 12, 12 are disposed between the pair of nozzle rings 12, 12. And a plurality of pins 15 that keep the interval constant.

The nozzle vane 11 includes a shaft portion 11b and a wing portion 11a. One end of the nozzle vane shaft portion 11 b is fitted to one end of the vane arm 14, and the nozzle vane blade portion 11 a rotates as the vane arm 14 rotates, so that the opening degree between the adjacent nozzle vanes 11, 11 can be adjusted.
The nozzle ring 12 is fixed to the turbine casing 22 and rotatably supports the shaft portion 11b of each nozzle vane. In the pair of nozzle rings 12, 12, for example, a plurality of through holes 12 a are formed at equal intervals for rotatably supporting the shaft portion 11 b of each nozzle vane. Further, the one 12 and the other 12 of the pair of nozzle rings are supported at a constant interval via a plurality of pins 15. Thereby, the wing | blade part 11a of each nozzle vane can be arrange | positioned between a pair of nozzle rings 12 and 12. FIG.

  The unison ring 13 is disposed on the outer surface side of one of the pair of nozzle rings 12 and is rotatably supported via a plurality of rollers 16. Along the inner surface side of the unison ring 13, a plurality of grooves 13 a that engage with one end side of the plurality of vane arms 14 are formed at equal intervals. Further, on the outer surface side of the unison ring 13, one drive groove 13 b that engages with one end side of the internal crank 17 is formed in order to drive the unison ring 13. As shown in FIG. 10, the internal crank 17 is rotatably held by the center housing, and is arranged so that one end side is engaged with the drive groove 13b and the other end side is engaged with the mounting portion of the drive mechanism (actuator). It is installed. An example of the drive mechanism is an actuator. An actuator rod (not shown) reciprocates due to the operation of the actuator, and the reciprocating motion is caused to rotate the internal crank 17 via an actuator mounting portion on the other end side of the internal crank 17 shown in FIG. In conversion, the unison ring 13 is rotated.

As shown in FIG. 2, the rotation of the unison ring 13 causes the vane arm 14 having one end engaged with the groove 13 a formed on the inner surface side of the unison ring 13 to rotate, and the shaft is fitted to the vane arm 14 accordingly. In addition, the nozzle vane blade portion 11a rotates to change the blade angle of the nozzle vane 11 so that the opening degree between the adjacent nozzle vanes 11 and 11 can be changed.
In the variable nozzle mechanism 23 having such a structure, sliding between the nozzle vane shaft portion 11b and the nozzle ring through hole 12a, sliding between the groove portion 13a of the unison ring 13 and the vane arm 14, and driving groove 13b of the unison ring There are sliding with the internal crank 17, sliding with the internal crank 17 and the center housing, etc., and wear resistance of these sliding parts (including moving parts) in order to improve the reliability of the turbocharger. Is required.

  In the present invention, these turbocharger parts are formed on the surface of the sliding part (including the movable part) in the variable nozzle mechanism 23 by injection molding or compacting, and the hardness after sintering is HRC55 to 65. The sliding members 13aa, 13ba, and 12aa, which are alloy sintered bodies having high hardness and high temperature wear resistance, are integrally joined or fitted together. As a result, a turbocharger part is provided in which a sliding member having high temperature wear resistance is integrated (composited) in the sliding portion, and the high temperature wear resistance of the sliding part of the turbocharger part is improved. .

  FIG. 3 shows an example of the arrangement of the sliding members. As shown in FIG. 3A, a sliding member 13aa is provided at a sliding portion between the groove 13a of the unison ring 13 and the vane arm 14, and a sliding portion between the driving groove 13b of the unison ring 13 and the internal crank 17 is provided. As shown in FIG. 3B, the sliding member 13ba has a cylindrical sliding member 12aa at the sliding portion between the shaft portion 11b of the nozzle vane and the through hole 12a of the nozzle ring 12, respectively. Arranged. In FIG. 3, the sliding member is disposed on the unison ring, but the sliding member may be disposed on the vane arm or on both.

  For example, it is preferable that a sliding member 13ba having a substantially U-shaped cross section as shown in FIG. 4 is integrally joined or fitted to the surface of the driving groove 13b of the unison ring 13. Thereby, the wear of the drive groove 13b of the unison ring that slides with the internal crank 17 that is the counterpart material is reduced. The shape of the sliding member disposed on the surface of the drive groove of the unison ring is not limited to this, but the inner surface shape is excellent in slidability according to the shape of the internal crank that is the counterpart material. Of course, it is preferable to have an outer surface shape that does not easily fall off from the drive groove portion of the unison ring and an outer surface shape that can be easily joined. Thereby, the reliability of the turbocharger can be improved. As the outer surface shape of the sliding member, as shown in FIG. 5A, considering the ease of joining, the ease of manufacture of the unison ring, which is the mating material, and the ease of processing. For example, the curved surface has a radius R, or, as shown in FIG. 5B, a part of the entire unison ring in the circumferential direction is a sliding member, and the outer surface (joining surface) is as straight as possible. And one or both of the ends having a substantially U-shaped cross section are formed in a convex shape, or the outer surface (joint surface) is a combination of a curved surface and a straight line, as shown in FIG. A shape is preferable.

  Further, as shown in FIG. 10, which is a sliding portion between the internal crank 17 and the center housing, a sliding member is formed on the inner surface of a through hole formed in the center housing so that the internal crank 17 can be inserted. Is preferably disposed. The sliding member provided on the inner surface of the through hole of the center housing is preferably provided in the through hole of the center housing by fitting such as press fitting. Thereby, wear of the center housing and the internal crank is reduced. 5 and 10, the sliding member is arranged on the unison ring side or the center housing side. However, the sliding member is arranged on the internal crank 17 side or on both sides. May be.

In addition, by making the sliding member by injection molding or compacting, it is possible to secure a sliding member having a desired dimensional shape with a small amount of processing, high accuracy, and high yield, economically. There is an advantage that it is advantageous. In particular, it is preferable to use injection molding from the viewpoint of enabling thinning with high accuracy and molding into a partially small shape.
The sliding member is made of alloy powder having high temperature wear resistance and further added with a binder such as thermoplastic resin, wax, vegetable oil, etc., and the mixture is heated and injected into the mold in a semi-molten state. Injection molding (metal powder injection molding (MIM)), or alloy powder, lubricant such as zinc stearate, shape-retaining agent such as paraffin wax, or additive materials such as machinability improving particles The mixture that has been added and mixed is charged into a mold and molded into a desired size and shape by compacting to obtain compacts by press molding or the like. The formed sliding member is subjected to a predetermined sintering process, and is made of an alloy sintered body having a hardness of HRC 55 to 65 and having high temperature wear resistance.

The alloy having high temperature wear resistance is preferably a Co-based alloy such as Trivalloy (registered trademark), for example.
Preferred examples of the Co-based alloy include alloys having a composition of Mo: 25 to 32%, Cr: 7 to 10%, Si: 2 to 3%, Fe + Ni: 3% or less, and the balance Co. In the case of this alloy, the sintering treatment is preferably performed at 1200 to 1300 ° C. in a vacuum or an inert atmosphere such as Ar gas. In addition, it is preferable to adjust the material of a sliding member within the range of an above-described composition according to the material of an other party material from a viewpoint of reduction of an opponent attack property.

Moreover, if the hardness of the sintered body is less than HRC55, there is a possibility that desired high temperature wear resistance cannot be ensured depending on the place of use. On the other hand, if the hardness exceeds HRC65, cracking is likely to occur or processing may be difficult, and the other party's aggression may increase.
Further, the material of the turbocharger parts such as the nozzle ring and unison ring is not particularly limited, and any commonly used gray cast iron product and ductile cast iron product can be used. In consideration of the use in a high temperature environment, it is preferable to use a material having excellent heat resistance, such as an austenitic stainless steel plate SUS310, a heat resistant steel plate SUH660, a high chromium cast iron product, or the like.

For gray cast iron products, various FCs specified in JIS G 5501 can be applied, and for ductile cast iron products, various FCDs specified in JIS G 5502 can be applied.
Moreover, high chromium cast iron products are in mass%, C: 1 to 1.4%, Si: 1.8 to 2.1%, Mn: 0.6% or less, Mo: 2 to 2.5%, Cr: 33 to 35%, Ni: 0.5% Hereinafter, it is preferable to use a cast iron product having a composition including the remaining Fe and inevitable impurities.

In the present invention, the sliding member made of an alloy sintered body having the above-described composition and hardness in the above-mentioned range and having high-temperature wear resistance is preferably used as a sliding part and / or a movable part of a turbocharger part. Are integrally joined or fitted to the surface layer of the part.
As a method of integrally joining or fitting the sliding member to the surface of the driving part of the nozzle ring or unison ring, welding such as TIG welding without using a molten material, laser welding, or vacuum or Ar gas is not used. Joining by sintering or brazing in an active atmosphere is suitable, and press-fitting, caulking, etc. are preferred as the method of fitting.

  For example, in the case of integration by sintering, after performing a predetermined sintering process on the sliding member in advance, the outer surface of the sliding member is processed so as to match the shape of the joining portion such as a unison ring, It is preferable that the sliding member is fitted into the joining portion, sintered, and integrally joined. Moreover, in joining by welding, it is preferable from the viewpoint of limiting the influence of welding heat to a narrow range by fitting a sliding member in a joining portion and joining by laser welding.

In addition, in order to reduce the deformation | transformation at the time of welding, it is preferable to make a welding location into the hatching part shown in FIG. 6, FIG. Welding may be performed continuously or in the form of dots. In addition, welding may be performed on both end surfaces of the sliding member or only one end surface, but it is preferable to use only one end surface from the viewpoint of relaxation of stress concentration.
In addition, when integrating by brazing, the outer surface of the sliding member is processed so as to match the shape (surface shape) of the joining part of the sliding part or the movable part, and the sliding part or the movable part is joined. It is preferable that after the brazing material is placed between the portion and the outer surface of the sliding member, the brazing material is heated to a predetermined temperature equal to or higher than the melting point of the brazing material and integrally joined. Alternatively, the outer surface of the sliding member or the surface of the sliding portion or the movable portion is further processed so as to match the shape (surface shape) of the joint portion of the sliding portion or the movable portion, and the sliding member is attached to the joint portion. It is preferable to place the brazing material at a predetermined position so that the brazing can be supplied to the joining interface, and then heat the brazing material to a predetermined temperature equal to or higher than the melting point of the brazing material and integrally bond.

  The brazing material used is preferably a brazing material having a liquidus temperature in the range of 800 to 1150 ° C. When the liquidus temperature is less than 800 ° C., the brazing material softens at the operating temperature of the turbocharger, and the desired joining characteristics cannot be secured. On the other hand, when the liquidus temperature is higher than 1150 ° C., it is necessary to increase the heating temperature for bonding, and the strength of the sliding member and the unison ring may be reduced. In addition, as for the brazing material to be used, it is more preferable that liquidus temperature is 900-1150 degreeC. As such a material, copper and copper alloy brazing, Ni and Ni alloy brazing, Au brazing, Pd brazing and the like are preferable from the viewpoint of heat resistance and corrosion resistance and easy processing into various shapes. The copper and copper alloy brazing are preferably those described as BCu-1 to BCu-4 defined in JIS Z 3262. Moreover, it is preferable to use the Ni brazing filler as described in JIS Z 3265 as BNi-1 to BNi-5. Moreover, you may use the mixed powder which mix | blended the appropriate powder with the appropriate quantity so that liquidus temperature might be the range of 800-1150 degreeC.

Further, the heating temperature for joining by brazing is preferably set to a temperature in the range above the liquidus temperature and 1200 ° C. or less, depending on the liquidus temperature of the brazing material. When the heating temperature exceeds 1200 ° C., the unison ring is deformed, and the dimensional accuracy is lowered and the strength of the sliding member and the unison ring may be lowered. In addition, More preferably, it is 950-1200 degreeC.
In addition, when performing integrated joining by brazing, the outer surface shape of the sliding member and / or the inner surface shape of the unison ring sliding part / movable part are adjusted so that the brazing material can be sufficiently supplied to the joining interface. It is preferable to do. An example of a preferable shape of the sliding member is shown in FIG.

  FIG. 8A shows an example in which a collar 13abc and a protrusion 13abd are provided on the sliding member 13ab. By providing the collar 13abc, it is possible to prevent the member from falling off when fitting the members, and further, the area of the bonding interface is increased and the bonding strength can be improved. Further, by providing the protrusion 13abd, the contact area with the internal crank 17 is increased, and the contact surface pressure can be reduced. Also, by providing the brim 13abc and the protrusion 13abd, it is possible to provide a place for the brazing material, to easily supply the brazing material to the joining interface, and to prevent the brazing material from flowing out during heating. And brazing work becomes easy.

  FIG. 8B shows an example in which a protrusion 13abd is provided on the sliding member 13ab, and a groove 13ac is formed on a part of the inner surface side of the unison ring sliding part / movable part. By providing the groove 13ac, a place where the brazing material can be placed can be secured, and the brazing material can be easily supplied to the joining interface. Furthermore, the groove 13ac and the protrusion 13abd can prevent the brazing material from flowing out during heating, facilitating the brazing operation.

FIG. 9 shows another preferred example in a cross-sectional view at the same position as in FIG.
In FIG. 9A, a groove 13ac is formed on the sliding member 13ab by the protrusion 13abd, a part of the sliding member 13ab, and a part of the unison ring 13 sliding part / movable part on the inner surface side. This is an example. In FIG. 9 (b), a protrusion 13abd is formed on the sliding member 13ab, and a groove 13ac is formed between the sliding member 13ab and the inner surface of the unison ring 13 sliding portion / movable portion. An example in which a shoulder portion 13abc is formed on the moving member 13ab side is shown. In this example, only the sliding member 13ab side needs to be processed, and the processing step can be shortened in that the inner surface side of the unison ring 13 sliding portion / movable portion is not required.

  Hereinafter, the present invention will be further described based on examples.

Example 1
A sliding member (size: outer diameter 33 mmφ × inner diameter 27 mmφ × thickness 7.5 mm) is used as a sliding member that is integrally joined to the surface of the drive groove of a SUS310 unison ring, and the high temperature valve seat wear tester shown in FIG. A test was carried out by inserting the setting plate and sliding the sliding material and the mating material (made of heat-resistant steel) to obtain an example of the present invention. In addition, the sliding material of the example of the present invention includes, in% by mass, a Co-based alloy powder containing Mo: 28.5%, Cr: 8.5%, Si: 2.5%, Fe + Ni: 0.4%, and having a composition composed of the balance Co. A mixture obtained by adding a binder and heating the mixture so as to be in a semi-molten state was molded by an injection molding machine and degreased and sintered to obtain a Co-based alloy sintered body. In addition, the hardness of the sintered compact was HRC57-61. On the other hand, the counterpart material was made of heat-resistant steel and processed into a valve shape. Assuming the case where the sliding member is not joined to the surface of the drive groove of the unison ring, the sliding material is made of SUS310 with nitriding treatment, and the counterpart material is made of refractory steel with nitriding treatment. As an example. The test conditions are as follows.
Test conditions;
Counter material heating temperature: 700 ℃
Counterpart rotation speed: 20 rpm
Spring load: 35 kgf (when set to 345 MPa)
Lift amount: 4.0 mm
Cam rotation speed: 2000 rpm
Test time: 5h
The heat source was LPG + Air, and the amount and amount of cooling water were constant.

After the test, the wear amount of the sliding material and the counterpart material was measured, and the total was calculated. The total amount of wear obtained was compared between the inventive example and the conventional example. As a result, during the test, the examples of the present invention and the conventional example showed changes in wear amount as shown in FIG. And after a test, the abrasion loss of the example of this invention is 1/2 of a prior art example (reference value), and it turns out that high temperature abrasion resistance has improved notably.
(Example 2)
In the variable nozzle mechanism shown in FIG. 1, the sliding member 13ab is integrally joined to the surface of the drive groove 13a of the unison ring made of SUS310.

  The sliding member 13ab is, in mass%, Mo: 28.5%, Cr: 8.5%, Si: 2.5%, Fe + Ni: 0.4%, and a binder is added to and mixed with a Co-based alloy powder having a composition consisting of the remaining Co. After heating the mixture so as to be in a semi-molten state, it is formed into a member shape having a collar and a projection as shown in FIG. The sintered body was brazed (joined). In addition, the hardness of the sintered compact was HRC57-61.

  At the time of joining, a groove portion was previously formed in the drive groove 13a in a shape that can be fitted with the flange 13abc of the sliding member. Then, the brazing material is placed at the position of the arrow in FIG. 8A so that the sliding member 13ab is fitted into the driving groove 13a and then the brazing material is sufficiently supplied to the joint interface between the driving groove and the sliding member. Was placed. The brazing material used was copper brazing (BCu-1) (liquidus temperature: 1083 ° C.). Next, the unit in which the sliding member 13ab was fitted into the driving groove 13a was heated to a heating temperature of 1120 ° C., the brazing material was melted, and the driving groove of the unison ring and the sliding member were integrally joined.

After joining, the joined part was visually observed and cut and inspected to confirm the presence or absence of defects in the joined part. As a result, there were no defects in the joint.
Next, a single fatigue test was conducted using the obtained unison ring as a test material to evaluate the quality of the joint. The test method was as follows.
A test material (unison ring) 13 is fixed to the driving side jig shown in FIG. An internal crank-shaped terminal disposed at one end of the fixed jig is slidably inserted into the driving groove 13b of the fixed test material (Unison ring). Then, a load was applied up to a predetermined number of tests (cycles) so that the internal crank-shaped terminal repeated sliding in the drive groove. The test conditions were as follows.
Test temperature: 25 ℃
Load load: ± 30kgf
Load cycle: 50Hz
Number of tests: 10 ⁷ cycles The material of the internal crank-shaped terminal, which is the sliding counterpart material of the unison ring drive groove, was a SUS310 nitride product.

After the test, the joint between the unison ring drive groove and the sliding member was visually observed for cracks and dropping.
As a result, neither a crack nor a drop was observed at the joint between the drive groove and the sliding member.

DESCRIPTION OF SYMBOLS 10 Variable turbocharger 11 Nozzle vane 11a Nozzle vane blade | wing part 11b Nozzle vane axial part 12 Nozzle ring 12a Through-hole 12aa sliding member 13 Unison ring 13a Groove part 13aa sliding member 13b Driving groove part 13ba Sliding member 14 Vane arm 15 Pin 16 Roller 17 Internal crank 20 Turbine (variable turbine)
21 Turbine wheel 22 Turbine casing 23 Variable nozzle mechanism 30 Compressor 31 Compressor wheel 32 Compressor casing 40 Bearing 41 Turbine rotor

Claims (6)

A turbocharger part having a sliding part and / or a movable part, the surface of the sliding part and / or the movable part is made of injection molding or powder molding , and has a hardness of HRC55 to 65, turbocharger parts sliding member is an alloy steel sintered body having a high-temperature wear resistance, characterized by comprising been integrally morning brazing.   The turbocharger part is one of austenitic stainless steel, high chromium cast iron, gray cast iron, and ductile cast iron, and the sliding member is a Co-based alloy sintered body, The turbocharger part according to claim 1.   When a turbocharger part is joined or fitted to the sliding part and / or the movable part of a turbocharger part having a sliding part and / or a movable part to form a turbocharger part, the sliding member is formed by injection molding or The sliding member is an alloy sintered body which is molded by compacting and has a hardness of HRC 55 to 65 and has high temperature wear resistance, and the outer surface of the sliding member, or further, the sliding portion and After processing the surface of the movable part so that the sliding member can be joined or fitted to the surface of the sliding part and / or the movable part, the sliding member is moved to the sliding part and / or the movable part. A method of manufacturing a turbocharger part, wherein the turbocharger part is integrally joined or fitted to the surface of the turbocharger.   The turbocharger part is one of austenitic stainless steel, high chrome cast iron, gray cast iron, and ductile cast iron, and the alloy having the high temperature wear resistance is a Co-based alloy. A method of manufacturing a turbocharger part according to claim 3.   The method of manufacturing a turbocharger part according to claim 3 or 4, wherein the joining is brazing.   The method for manufacturing a turbocharger part according to claim 5, wherein the brazing material used in the brazing is a brazing material having a liquidus temperature in the range of 800 to 1150 ° C.

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