JPH09268315A - Surface finishing method for metallic member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a surface finishing method for a metallic member capable of surely improving the surface roughness with efficiency and furthermore capable of controlling the residual stress. SOLUTION: Melting under heating in which only the surface of the surface finish desired part 20 in a metallic member 2 is melted to form a surface melted layer is executed, next, the surface melted layer is cooled to form a resolidified layer, and after that, the surface finish desired part 20 is reheated. The melting under heating and the reheating are executed preferably by the irradiation of high density energy beams.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method of finishing a surface of a metal member (a method of improving surface roughness) and a method of controlling residual stress associated therewith.

[0002]

2. Description of the Related Art Conventionally, the following method has been known as a surface finishing method for improving the surface roughness of a metal member and smoothing it. For example, surface polishing is performed by polishing the projections existing on the member surface with abrasive paper or polishing powder, burnishing is performed by crushing the projections existing on the surface of the member with a roller, and the surface of the member is polished by a metal brush. There is known a method such as buffing for finishing so that the convex portions existing in the are rounded.

In all of these surface finishing methods, the convex portions existing on the surface of the member are removed by mechanical means, and they are efficient treatment methods as compared with chemical polishing or the like. However, under the present circumstances, further reduction of processing time is strongly desired. Further, in the above mechanical means, there is a problem that tool management for maintaining accuracy is very troublesome.

On the other hand, as a method of solving the problems of the surface finishing method by the mechanical means and performing the surface finishing of the metal member with high processing capacity, only the surface of the desired surface finishing portion of the metal member is heated and melted. A method has been proposed in which the state is set and immediately after that, solidification is performed (Japanese Patent Application No. 8-44).
107).

According to this method, the surface of the desired portion is brought into a molten state, the surface roughness is rapidly improved by the action of the surface tension of the molten portion, and then solidification is performed in that state. It Therefore, smoothing of the surface is achieved in an extremely short time without the need for special tools.

[0006]

However, the above-described conventional surface finishing method for metal members has the following problems.
That is, according to the method of finishing the surface in the molten state, the excellent surface finishing effect (surface roughness improving effect) is obtained, while tensile residual stress is generated during resolidification of the surface molten layer. This tensile residual stress not only causes distortion after the surface finishing treatment, but also easily causes cracks and breakage.

The present invention has been made in view of the above conventional problems, and the surface roughness of a metal member capable of improving the surface roughness efficiently and surely and controlling the residual stress. It is intended to provide a finishing method.

[0008]

According to a first aspect of the present invention, melting heating is performed to melt only the surface of a desired portion for surface finishing of a metal member to form a surface molten layer, and then the surface molten layer is cooled to re-solidify the layer. Is formed, and then the desired portion for surface finishing is reheated, which is a surface finishing method for a metal member.

What is most noticeable in the present invention is that the above-mentioned melt-heating forms the above-mentioned surface-melted layer, which is then cooled and re-solidified, and then the above-mentioned re-heating is further performed. Examples of the metal member targeted by the present invention include a member made of an iron-based metal such as steel and a non-ferrous metal such as aluminum or an aluminum alloy.

The above-mentioned melting and heating is performed at a temperature at which only the surface of the metal member is melted as described above. However, only the surface portion is melted. When the metal member is entirely melted, its shape, mechanical properties, etc. are entirely changed, which is not preferable. Therefore, in the above-mentioned melting heating, only the surface of the metal member is melted, and the lower portion is heated so as not to melt.

Next, the cooling rate after formation of the surface molten layer is not particularly limited. However, in the case of materials that are hardened by rapid cooling, such as steel and heat-treatable aluminum alloys, cooling at a certain cooling rate or more can improve the surface roughness as well as the surface roughness. it can.

The reheating is performed at a lower temperature than the melting heating. That is, it is performed at a temperature at which the surface does not melt. Further, the lower limit of the reheating temperature may be higher than or equal to the temperature at which residual stress can be relaxed. In this case, for example,
When the metal member is a steel material, it can be carried out at the same temperature as tempering after usual quenching.

Next, the operation of the present invention will be described. In the surface finishing method for a metal member of the present invention, a desired surface finishing portion of the metal member is melt-heated to form a surface-melted layer, and then the re-heating is performed after the surface-melted layer is re-solidified. Therefore, it is possible to surely and quickly improve the surface roughness of the desired portion of the surface finish of the metal member and to sufficiently remove the residual stress.

That is, the surface melting layer is formed by the melting and heating, and the surface tension of the molten state flattens the surface of the surface melting layer. Next, the flattened surface-melted layer is cooled and resolidified while maintaining its flat state. As a result, the surface roughness of the desired surface finish portion is improved in an extremely short time. On the other hand, in this state, as described above, during the re-solidification,
Tensile residual stress is generated by solidification shrinkage.

Next, the desired portion for the surface finish is reheated. The reheating temperature is lower than the melting heating temperature and is a temperature at which residual stress can be relaxed. for that reason,
The tensile residual stress is surely removed from the reheated portion. Therefore, the tensile residual stress can be reliably removed while maintaining the surface roughness improved state.

Next, as in the invention of claim 2, the reheating is partially performed on the desired portion of the surface finish,
It can be performed so that the reheating part which reheats and the non-reheating part which does not reheat are formed adjacent to each other. This is effective in the following cases. That is, for example, when the metal member is a quench-hardenable material, it is possible to improve the surface hardness in addition to improving the surface roughness by quenching after melting and heating.

In this case, the effect of improving the surface hardness is reduced by performing the reheating. Therefore, while the reheating is partially performed on the desired portion of the surface finish to form the reheating portion in which the residual stress is relaxed, the remaining non-reheating portion is in a state in which the hardness improving effect remains. To do. By forming the reheated portion and the non-reheated portion so as to be adjacent to each other, it is possible to balance the overall residual stress while maintaining the hardness improving effect.

Next, as in the third aspect of the invention, it is preferable that the melting heating and the reheating are performed by irradiating a high density energy beam. As a result, it is possible to perform the melting heating and the reheating with good response, and it is possible to efficiently improve the surface roughness and remove the residual stress particularly in the desired surface finishing portion of the metal member.

Therefore, the method using the high-density energy beam is particularly effective when it is desired to finish only the desired surface finish portion of the metal member. Examples of the high-density energy beam include an electron beam,
There are laser beams and high-density energy such as high-frequency heating that is not a beam. In the present invention, these are collectively called high-density energy beams.

The electron beam is generated by applying a high voltage to the electron beam gun. Also, the laser light is
It is generated by applying a high voltage to the laser oscillator. Then, the high-density energy beam is added to a desired surface finishing portion of the metal member, and is individually and partially irradiated at each time of the melting heating and the reheating.

Next, as in the invention of claim 4, the high-density energy beam is first melted by using the melting heating beam for performing the melting heating and the reheating beam for performing the reheating. Surface finishing with a beam for melting and heating Melting and heating to melt only the surface of the desired part to form a surface-melted layer, and then the re-solidified layer formed by cooling the surface-melted layer is irradiated with the beam for re-heating. There is a method to do by doing.

In this case, in order to irradiate the desired portion for surface finishing of the metal member with the melting heating beam and the reheating beam sequentially or intermittently, the two heat treatments (the surface melting layer) are performed. And the reheating of the resolidified layer) can be continuously performed. Therefore, the formation of the surface-melted layer and the reheating of the re-solidified layer can be performed more responsively.

The cooling of the surface molten layer can be achieved by providing a slight time interval between the irradiation of the melting heating beam and the irradiation of the reheating beam. That is, during this time interval, the heat applied to the desired portion for surface finishing by the beam for melting and heating is rapidly transferred into or out of the metal member, and the metal member is rapidly cooled. The time interval may be equal to or longer than the time for the surface molten layer of the metal member to resolidify.

Further, as in the fifth aspect of the invention, the high-density energy beam can be irradiated by dividing the beam emitted from the beam generating source at one location into a plurality of locations. In this case, one high-density energy beam is divided into a plurality of beams by a deflection control device or the like. This gives 1
The high-density energy beam of the book can be simultaneously distributed and irradiated to desired plural portions of the metal member, and the irradiation equipment can be downsized.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 A surface finishing method for a metal member according to an embodiment of the present invention will be described with reference to FIGS. That is, as shown in FIG. 1, the surface finishing method of the metal member of this example is such that the desired surface finishing portion 20 of the metal member 2 as the material to be treated is used.
Is melted and heated to form a surface melted layer 21, and then the surface melted layer 21 is cooled to form a re-solidified layer, and then the surface finishing desired portion 20 is reheated.

That is, as shown in FIG. 2, the desired surface finishing portion 20 is once heated to a temperature 31 above the melting temperature T ₃ , then cooled, and then reheated 32 above the residual stress releasable temperature T _2. It is heat-treated by the heat pattern of being reheated to.

Further, as shown in FIG. 1, the fusion heating and the reheating in the present example are performed by the high density energy beam 11,
It is carried out by irradiating with 12. In other words, Figure 1
As shown in (a) and (b), a high-density energy beam 10 is emitted from a high-density energy beam source 1, and this beam is distributed to a melting heating beam 11 and a reheating beam 12 by a deflection lens.

The irradiation of the beams 11 and 12 is as follows.
As shown in FIG. 1, this is performed while moving the metal member 2 in the direction of the arrow in the figure. As a result, first, the beam 11 for melting and heating is applied to the desired surface finish portion 20,
The irradiated portion 21 is melted and heated to form a surface melted layer.

Next, the surface-melted layer is cooled by self-cooling and changes into a re-solidified layer. Then, by further moving the metal member 2 in the direction of the arrow in FIG. 1, the resolidification layer of the surface melting layer 20 is irradiated with the reheating beam 12,
The irradiated portion 22 is reheated.

As described above, according to the method using the high-density energy beam of this example, a series of treatments in which a surface melting layer and a resolidification layer are sequentially formed on a desired portion of the surface finish and then reheating is performed is extremely short. Can be done in time. Therefore, the surface roughness of the desired surface finish portion 20 is improved and residual stress is removed in an extremely short time. Further, the troublesomeness of tool management, which is required in the conventional mechanical means, is eliminated. Therefore, surface finishing without residual stress can be performed very efficiently.

Further, by using the high-density energy beam, it is possible to surface-finish not the entire metal member 2 but only the desired surface-finishing portion 20 and reheat to remove the residual stress. . That is, only a part of the metal member 2 can be surface-finished without generating residual stress.

Embodiment 2 As shown in FIG. 3 and FIG. 4, this embodiment is the same as the above-described method for finishing the surface of the metal member of Embodiment 1, except that the metal member 2
A heat treatment apparatus and method for continuously irradiating the ring-shaped surface finishing desired portion 20 (FIG. 4) of the metal member 2 with the melting heating beam 11 and the reheating beam 12 while rotating the Is.

The metal member 2 as the material to be treated in this example is a steel material and is a lock-up clutch piston of a component for a torque converter. This piston has a dish shape (see FIGS. 3 and 10). Then, a ring-shaped surface finish is applied to a part of it (Fig. 4).

As shown in FIG. 3, the heat treatment apparatus includes a processing chamber 19 in which the metal member 2 is placed, a source 1 for irradiating the processing chamber 19 with the melting heating beam 11 and the reheating beam 12, It has deflection coils 111 and 112 for distributing the high-density energy beam 10 from the beam generation source 1 to the melting heating beam 11 and the reheating beam 12.

Further, it has a vacuum exhaust device 16 for reducing the pressure in the processing chamber 19, and a high-speed deflection control device 110 for the high-density energy beams in the deflection coils 111, 112. The outputs of both beams can be arbitrarily distributed by changing the frequency and the waveform of the current flowing through the deflection coils 111 and 112. A rotation motor 150 for rotating the mounting table 15 for the metal member 2 is provided below the processing chamber 19. These devices are integrated control unit 17
Is controlled by

In performing the surface finishing method for the metal member by the heat treatment apparatus, first, the rotary motor 150 is driven to rotate the metal member 2 in the direction of the arrow in FIG. Further, the inside of the processing chamber 19 is evacuated by the vacuum exhaust device 16.

Then, as shown in FIGS. 3 and 4, the metal member 2 is irradiated with the beam 11 for melting and heating, followed by the beam 12 for reheating with a slight time difference. As a result, as shown in FIG. 4, the metal member 2 can be subjected to a ring-shaped surface finish in which residual stress is sufficiently removed. Also, in this example, the same effect as that of the first embodiment can be obtained.

Embodiment 3 As shown in FIGS. 5 and 6, this embodiment uses the heat treatment apparatus and the surface finishing method shown in Embodiment 2 to carry out the above reheating to the desired surface finishing portion 20 of the metal member 2. Partial heating was performed so that a reheating portion A that reheats and a non-reheating portion B that does not reheat are formed adjacent to each other. Others are the same as the second embodiment.

Specifically, the reheating beam 12 generated in the heat treatment apparatus was repeatedly turned on and off at regular intervals. That is, as shown in FIG. 5, the portion corresponding to the reheating portion A is irradiated with the reheating beam 12,
In the portion corresponding to the non-reheating portion B, the reheating beam 12
Irradiation was stopped. As a result, as shown in FIG. 6 (b), the reheating part A is subjected to the above-mentioned melting heating and reheating to perform surface finishing and removal of residual stress, while the non-reheating part B is subjected to the above-mentioned melting. Only the heating is applied and only the surface finish is applied, resulting in a tensile residual stress state.

On the other hand, the metal member 2 which is the non-treated material of this example
Is a steel material as described above. Further, the self-cooling after the melting and heating is performed at a sufficiently high cooling rate after the heating is completed, because the melting and heating is performed only on a part of the metal member 2 for a short time. Therefore, while the surface-melted layer changes to the resolidified layer, the resolidified layer and a portion of the lower layer having a certain depth undergo a transformation from austenite to martensite and are hardened. On the other hand, when the cured desired surface finish portion 20 is reheated, residual stress is removed and the curing effect is lowered.

That is, the reheating section A is shown in FIGS.
As shown in (b), the surface finish is performed in the state 82 (FIG. 7 (b)) in which the residual stress is removed, and a relatively soft portion is formed. On the other hand, the non-reheating part B is shown in FIG. 6 and FIG.
As shown in FIG. 7, the surface finish is performed in the state 81 (FIG. 7A) in which the residual tensile stress is left, and the portion has a relatively high hardness.

Therefore, by forming the reheated portion A and the non-reheated portion B adjacent to each other, as shown in FIGS.
As shown in, when the entire surface finishing desired portion 20 is viewed,
A state 83 (FIG. 7C) in which the residual stress is small on average is obtained, and the state of high hardness can be finished on average. Therefore, it is very effective when processing a metal member that requires a surface finish and requires a certain degree of hardness. In addition, the same effects as those of the second embodiment can be obtained.

Embodiment 4 In this embodiment, as shown in FIGS. 8 and 9, the reheating portion A and the non-reheating portion B are arranged vertically and horizontally adjacent to each other in a checkered pattern in the embodiment 3. That is, by using the same apparatus and method as in the third embodiment, a plurality of ring-shaped surface finishes are sequentially shifted in the radial direction for each rotation with respect to the desired surface finish portion 20 of the metal member 2. went. Others
This is the same as the third embodiment.

In this case, the reheating part A and the non-reheating part B are arranged in a good balance in both the vertical and horizontal directions, and the effects of the third embodiment can be made more effective.

Embodiment 5 This embodiment is a specific example using the surface finishing method and apparatus for metal members shown in Embodiment 1 and Embodiment 2. That is, the metal member 2 as the article to be processed in this example is as shown in FIG.
As shown in 0, it is the lock-up clutch piston 41 used in the torque converter. The lockup clutch piston 41 is made of steel.

This lockup clutch piston 41
In the torque converter, is partially caulked and fixed to a damper device for absorbing fluctuations in transmission torque. Reference numeral 43 in the figure is a mounting hole. As shown in FIG. 10, the damper device includes a driven plate 51 that is rotated integrally with the turbine liner.
And springs 52, 53 and the like.

Here, as shown in FIG. 10, the spring 5
2 is for the first stage, which is arranged at eight locations in the circumferential direction of the lockup clutch piston 41,
Further, the spring 53 is the lockup clutch piston 4
1 for the second stage, which is arranged at four locations in the circumferential direction of 1, and this spring 53 is
Every two of them are arranged in two. In addition, the spring 5
3 has a diameter smaller than that of the spring 52 and is set to be shorter. The torsion angle of the spring 52 reaches a set value, and the transmitted torque starts to bend after reaching the bending point torque.

Therefore, the rotation transmitted from the front cover via the friction material is transmitted to the turbine hub via the damper device. At this time, the springs 52 and 53 contract and the transmission torque of the transmission torque is transmitted. Absorb fluctuations. In addition, it also plays a role of preventing vibration, noise, and the like caused by the transmission of "rapid changes in the output torque of the engine" to a transmission (not shown).

By the way, during the normal drive of the lock-up clutch piston 41 (when the lock-up clutch device is placed in the engaged state and the lock-up clutch piston 41 rotates counterclockwise in FIG. 10) and during the reverse drive. (When the lock-up clutch piston 41 rotates clockwise in FIG. 10 due to engine braking, etc.)
Since the spring 52 is compressed, the spring 52 tends to repeatedly slide on the flat plate portion 411 of the lockup clutch piston 41.

Therefore, there is a problem in that the flat plate portion 411 of the lockup clutch piston 41 causes friction due to sliding with the spring 52. The lock-up clutch piston 41 has a donut-shaped spring receiver 40 portion (hatched portion in FIG. 10) that contacts the spring 52.

The spring receiver 40 of the lock-up clutch piston is required to have low surface roughness and smoothness. Therefore, the spring receiving part (thickness 3mm)
It is necessary to partially apply a surface finish. The material of the above parts is S23C.

Further, in the surface finishing, the electron beam as the high-density energy beam shown in Embodiments 1 and 2 was used for the above melting heating and reheating. The electron beam generator has a maximum output of 5 KW, and can distribute and emit a 3.5 KW electron beam as the melting heating beam 11 and a 1.5 KW electron beam as the reheating beam 12.

Then, the above parts are rotated at 10 rpm, and the melting heating beam 11 and the reheating beam 12 are positioned at a radius 127 mm as shown in the first embodiment.
Was continuously and sequentially irradiated. Also, both beams 11 and 12
The interval between and was 20 mm. That is, in the metal member 2,
The melting heating beam 11 and the reheating beam 12 are
Irradiation was continuously performed at a feed rate of about 8 m / min while maintaining the interval of mm. Further, the surface finish portion of the metal member 2 is sufficiently cooled by self-cooling between the irradiation of the melting heating beam 11 and the irradiation of the reheating beam 12.

The surface thus heat-treated is sufficiently surface-finished and residual stress is removed. The measurement results of the surface roughness of this surface-finished part were measured together with the part that was not surface-finished. The result is shown in FIG. As is known from FIG. 11, it can be seen that the surface-finished portion in this example has a significantly improved surface roughness compared to the other portions. As a result of residual stress measurement, almost no residual stress remained in the surface-finished part.

Embodiment 6 This example shows an example of the locus of the irradiation part of the electron beam in FIG. In this example, the electron beam has two circular deflection trajectories C ₁ , C
Irradiate according to ₂ . In this case, each circular deflection locus C ₁ ,
C ₂ irradiates the heat-treated regions 25 and 26, respectively, that is, the regions corresponding to the melting heating beam irradiating portion and the reheating beam irradiating portion, with an electron beam, during which,
The member to be processed is rotated around its central axis. Accordingly, the trajectory of the electron beam in the heat treatment regions 25 and 26 moves in the direction of arrow H.

The circular deflection loci C ₁ and C ₂ generate sinusoidal deflection waveforms in the x-axis direction and the y-axis direction,
It is formed by the combination of the deflections. Further, since the circular deflection loci C ₁ and C ₂ are switched to alternately irradiate the electron beams in the heat-treated regions 25 and 26, a deflection waveform w ₁ as shown in FIG. 13 is generated, and the deflection waveform w ₁ is generated. ₁
And the deflection waveform in the y-axis direction are superimposed.

Therefore, the time t ₁ when the voltage V _E takes a positive value
Is irradiated electron beam to be heat-treated region 25 between, the voltage V _E electron beam is irradiated to the heat treatment area 26 during the time t ₂ to a negative value. Further, by adjusting the lengths of the deflection waveform w _{1 for} the times t ₁ and t ₂ , it is possible to adjust the irradiation energy to the heat-treated regions 25 and 26.

Embodiment 7 In this embodiment, as shown in FIG.
9 shows another example in which an electron beam is irradiated to the light source. In this case, the electron beam is irradiated by two surface deflection trajectories C ₃ and C ₄ . That is, the electron beam is applied to the regions to be heat-treated 27 and 28 by the respective surface deflection trajectories C ₃ and C ₄ , during which the member to be processed is rotated around its central axis. Therefore, also in this case, the heat treatment region 27,
The trajectory of the electron beam at 28 moves in the direction of arrow H.

The surface deflection loci C ₃ and C ₄ are formed by generating a triangular wave deflection voltage in the x-axis direction and the y-axis direction. Also, each surface deflection locus C ₃ , C ₄
And the electron beam is irradiated to the heat-treated regions 27 and 28, the deflection waveform w ₁ as shown in FIG.
And the triangular waves in the x-axis direction and the y-axis direction are superimposed. Of course, combining circular and surface deflection,
The electron beam can be deflected so as to follow a locus such as an ellipse. Others are the same as those in the sixth embodiment.

By the way, in the above embodiment, an example of treating the lockup clutch piston of the torque converter has been described, but in addition to that, the surface of the oil pump plate, the seal ring, etc. is smoothed while partially controlling the residual stress. The present invention can be applied to any metal member that needs to be formed regardless of its material, shape, size, or the like.

Embodiment 8 As shown in FIGS. 16 and 17, this embodiment is an example in which the outer surface 205 of the rising portion of the round tray-shaped metal member 2 (FIG. 17) is surface-finished by the method of the present invention. . Further, as shown in FIG. 16, the apparatus used in this example has the rotation axis of the rotation apparatus portion of the material to be processed in the second embodiment in the horizontal direction, that is, the rotation axis of the rotation motor 150 and the mounting table 15. Changed to horizontal. Others are the same as the second embodiment.

In this example, the melting heating beam 11 and the reheating beam 1 are rotated while rotating the round tray-shaped metal member 2 with the central axis being horizontal as shown in FIG.
And 2 are sequentially and successively irradiated. As a result, even the outer surface 205 of the rising portion of the round tray-shaped metal member 2 can be easily surface-finished in a short time without residual stress. Others are the same as in the fifth embodiment.

[0063]

According to the present invention, it is possible to provide a surface finishing method for a metal member capable of efficiently and surely improving the surface roughness and controlling the residual stress.

[Brief description of drawings]

FIG. 1A is a side view and FIG. 1B is a plan view showing an irradiation state of a high-density energy beam in a first embodiment.

FIG. 2 is an explanatory diagram showing a heat pattern of a desired portion for surface finishing in the first embodiment.

FIG. 3 is an explanatory diagram of a heat treatment apparatus according to the first embodiment.

FIG. 4 is an explanatory diagram showing an irradiation state of a high-density energy beam according to the second embodiment.

FIG. 5 is an explanatory diagram showing a high-density energy beam irradiation state in the third embodiment.

6A, 6B, 6C, 6D, 6E, 6F, 6C, 6D, 6E, 6F, 6G, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6G, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6E, 6D, 6E, 6D, 6E, and 6D, respectively.
Explanatory diagram showing the arrangement state of.

FIG. 7 (a) non-reheating part in Embodiment 3;
Explanatory drawing which shows the residual stress state in (b) reheating part and (c) whole.

FIG. 8 is an explanatory diagram showing an irradiation state of a high-density energy beam according to the fourth embodiment.

FIG. 9 is an explanatory diagram showing an arrangement state of a reheating unit and a non-reheating unit according to the fourth embodiment.

FIG. 10 is an explanatory diagram of a lockup clutch piston according to the fifth embodiment.

FIG. 11 is an explanatory diagram showing a surface roughness measurement result in the fifth embodiment.

FIG. 12 is an explanatory diagram showing an example of a trajectory of an electron beam irradiation unit in the sixth embodiment.

FIG. 13 is an explanatory diagram showing the irradiation state of a high-density energy beam in the sixth embodiment.

FIG. 14 is an explanatory diagram showing another example of the trajectory of the electron beam irradiation unit in the seventh embodiment.

FIG. 15 is an explanatory diagram showing an irradiation state of a high-density energy beam according to the seventh embodiment.

FIG. 16 is an explanatory diagram of a heat treatment apparatus according to the eighth embodiment.

FIG. 17 (a) of a metal member in Embodiment 8.
The front view, (b) GG line arrow sectional view.

[Explanation of symbols]

 1. . . Source of high-density energy beam, 10. . . High-density energy beam, 11. . . Beam for melting and heating, 12. . . Reheating beam, 2. . . Metal member, 20. . . Surface finish desired part, A. . . Reheating part, B. . . Non-reheating part,

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Takuji Obayashi Takuji Obayashi 10 Takane, Fujii-cho, Anjo-shi, Aichi Aisin AW Co., Ltd. (72) Takatoshi Suzuki 41 Address 1 Toyota Central Research Institute Co., Ltd.

Claims (5)

[Claims] 1. A surface finish of a metal member is performed by melting and heating only a surface of a desired portion to form a surface-melted layer, then cooling the surface-melted layer to form a re-solidified layer, and then the surface. A surface finishing method for a metal member, which comprises reheating a desired portion. 2. The reheating according to claim 1, wherein the reheating is partially performed on the surface finishing desired portion, and a reheating part for performing reheating and a non-reheating part for not performing reheating are adjacent to each other. A surface finishing method for a metal member, the method comprising: 3. The surface finishing method for a metal member according to claim 1, wherein the melting heating and the reheating are performed by irradiating a high density energy beam. 4. The fusion heating beam according to claim 3, wherein the high-density energy beam is a fusion heating beam for performing the fusion heating,
By using the reheating beam for performing the reheating, first, the melting heating beam is used to melt only the surface of the desired portion for surface finishing to form a surface-melted layer,
Then, on the re-solidified layer formed by cooling the surface molten layer,
A surface finishing method for a metal member, which is performed by irradiating the reheating beam. 5. The surface finish of a metal member according to claim 3 or 5, wherein the high-density energy beam is a beam emitted from a beam generation source at one location and is distributed to a plurality of locations for irradiation. Method.