WO2004046395A1 - Method of setting ultrasonic shock treatment conditions for metal material - Google Patents

Abstract

A method of setting ultrasonic shock treatment conditions for a metal material for determining treatment conditions, particularly, a treatment temperature range according to the degree of a target reformation of the treated metal material when the metal material surface layer part is subjected to an ultrasonic shock treatment, characterized by comprising the steps of selecting, as a required effect by the ultrasonic shock treatment, one or a plurality of effects from the improvement of fatigue strength, reformation of surfaces, and improvement of weld cracking in the treated metal material, determining an ultrasonic shock treatment temperature for each effect, setting the conditions for the ultrasonic shock treatment, and finally determining the efficient combination of these steps.

Description

Setting method of ultrasonic shock treatment conditions for metallic materials

Technical field

 According to the present invention, when performing an ultrasonic impact treatment on the surface layer of a metal material, the processing conditions, particularly the processing temperature, are adjusted according to the target modification degree of the target metal material.

It relates to a method of setting ultrasonic impact processing conditions that determine the range and combinations thereof. Rice field

Background art

 The durability of metal products is often determined by fatigue and corrosion. Various approaches have been taken to improve these. In order to improve fatigue, it has been practiced to improve the toe shape to reduce stress concentration and to apply compressive residual stress by using grinding and various kinds of peung. As for corrosion, coatings such as painted ones, non-conductive coatings such as stainless steel, and protections such as weathering steel that provide protection 鲭 to reduce the amount of corrosion have become practical. I have.

 As described above, to improve the durability of metal products, it can be said that at present, there are two methods that can be roughly divided into post-processing after production and methods for improving the material itself.

Of these, regarding the improvement of materials and their performance, recently, according to the Journal of Material Science Technology. Vol. 15, No. 3, 1999, the crystal structure of the surface layer of a metal material was changed to nanometer (nm). By obtaining a so-called nanocrystalline structure with an appropriate size in units of, for example, 100 to ⁹ m), for example, 100 nm or less, superior In order to obtain a metal material having this nanocrystalline structure, it is known to obtain properties such as ultra-high strength. For example, the metal material is made into an amorphous state and then subjected to a low-temperature heat treatment. is there. In order to obtain the amorphous state, there are methods such as rapid quenching of a metal material or sputtering film formation. In this case, a variety of manufacturing methods are required to obtain a widely used shaped body or structure. There are restrictions. In addition, the powder of the metal material is treated with a pole mill or the like, and the surface of the metal material is subjected to strong working, thereby converting the metal material into an amorphous form and then heat-treating the amorphous material. A metal powder having a nanocrystalline structure can be obtained. This metal powder can be pressed at a high temperature or subjected to a treatment such as welding to form a structure. However, since the nanocrystalline structure grows and disappears through the high-temperature heat treatment process, it is difficult to obtain a molded product or a structure utilizing the characteristics of the nanocrystalline structure. .

On the other hand, in the technology belonging to the post-processing among the above-mentioned methods for improving the durability, the surface of the metal material is subjected to an ultrasonic impact treatment to give a plastic deformation to the surface or to release the residual stress. For example, a method of applying ultrasonic impact treatment to a welded portion of a metal material to release residual stress in the welded portion, reduce minute defects such as voids and abnormal grain boundaries, and improve fatigue performance. Methods of improvement, for example, Transactions of the Japan Society of Mechanical Engineers (C), Vol. 67, No. 657 (2001-5), Japanese Unexamined Patent Application Publication No. Hei 9-234, 855, Japanese Unexamined Patent Application Publication No. And US Patent No. 6,338,765. In addition, as a device for performing the above-described ultrasonic shock treatment, a transducer that generates an ultrasonic wave, a waveguide for guiding the ultrasonic wave to the tip, and a vibration provided by the ultrasonic wave provided at the tip. U.S. Patent Application Launches Ultrasonic Shock Processor with Head to Hold Rotating Shock Pins It is known from US Pat. No. 2,002,000. However, in this force method, the temple B (Journal of Material Science Technology. Vol. ID, No. 3, 1999, Institute of Solid-State Physics, Academy of Science of the USSR. No. 7, pp. 14 -16, July, 1988, it is also known to improve the surface crystallographic structure, meaning that this technique has the property of improving the material as well as being a post-treatment.

 However, conventional ultrasonic impact treatment mainly focuses on improving fatigue strength and reducing minute defects.Even if the material properties and surface modification of the surface layer of a metal material are improved, it is a byproduct, its range and degree This has occurred in situations where there is a great deal of variation, and it has not yet reached the point of independent control and improvement according to the purpose.

 The studies of the effects using the various ultrasounds described above have been performed independently and individually for each effect, and despite the fact that the processing is performed using almost the same equipment, The necessary conditions and effects for these treatments have not been treated in a unified design concept, and the necessary effects for the metal workpiece to be treated have not been properly and selectively obtained. In particular, with regard to the temperature among the conditions, only the rough high-temperature state “during welding” and the normal temperature were examined, and this is the situation that narrowed the possibility of this ultrasonic impact treatment.

 As a result, it can be said that the current situation regarding fatigue and corrosion of metal products has the following issues.

 1) When metal materials are welded, the characteristics made with steel materials are often impaired at the welds. In such cases, the welds are supplemented by means such as painting.

2) When using ultrasonic waves to reduce residual stress during welding solidification, the effect of improving fatigue strength is limited, and the effect of improving the toe shape is limited. can not see.

 3) Although ultrasonic impact treatment has the effect of improving fatigue strength, high-strength steel is more plastic in terms of toe shape improvement effect, although high-strength steel is more advantageous in terms of residual stress improvement effect. It tends to be less deformable, and the treatment efficiency tends to decrease, and the effect of the treatment layer thickness in the depth direction tends to decrease.

 4) In aircraft, etc., technology to restore the accumulated dislocation by heating by inserting the part where fatigue occurs into the furnace and heating it, but it is impractical to apply such technology to large structures such as bridges. It is.

 In this way, regardless of the size of the structure in the atmosphere, the desired fatigue strength, and the high-strength part, there is no description of the combination of the target for reforming the target metal material and the processing conditions including the processing temperature range. It is not clear yet. Disclosure of the invention

 The present invention relates to a method for setting ultrasonic impact processing conditions for determining a processing condition including a processing temperature range in accordance with a target degree of modification of a target metal material when performing an ultrasonic impact treatment on a metal material surface layer. The purpose is to provide. The present invention has been made to solve the above problems, and the gist thereof is as follows.

 (1) For the metal material to be treated, any one or more of the effects of fatigue strength improvement, surface modification, and welding crack improvement are selected as the effects of the required ultrasonic impact treatment. After determining the ultrasonic shock treatment temperature according to each effect, set the conditions of the ultrasonic shock treatment, and finally determine the efficient combination of those treatments. How to set sonic impact processing conditions.

(2) The ultrasonic impact treatment aims to improve the fatigue strength of newly-formed workpieces. If the welding toe treatment is inefficient, determine the ineffectiveness of the weld toe treatment based on the metal strength of the new workpiece. If not, determine the processing temperature from the temperature dependence of the metal strength. Efficient conditions to improve the toe shape by performing ultrasonic shock treatment at the temperature determined in the lowering process and to apply compressive residual stress again at room temperature if you want to apply compressive residual stress again (1) The method for setting ultrasonic shock treatment conditions for a metal material according to (1).

 (3) If the ultrasonic impact treatment is intended to improve the fatigue strength of the existing work, it is determined whether the weld toe treatment is inefficient based on the metal strength of the existing work. After determining the ultrasonic impact treatment temperature from the temperature dependence of the metal strength, heating to the determined temperature, ultrasonic impact treatment is performed to improve the toe shape, and compressive residual stress is applied If desired, the ultrasonic impact treatment is performed again at room temperature under conditions necessary to introduce compressive residual stress. The method for setting the ultrasonic impact treatment conditions for a metal material according to (1), wherein:

 (4) If the ultrasonic impact treatment is intended to recover the accumulated fatigue of the existing workpiece, a process appropriate for the recovery of the transition accumulated due to the repeated stress from the state diagram of the metal material of the existing workpiece. After the temperature is determined, the ultrasonic impact processing conditions are determined from the relationship between the processing temperature and the processing pattern, and the ultrasonic impact processing is performed by judging the processing under heating or at room temperature (1). A method for setting the ultrasonic impact processing conditions of the metal material described.

(5) If the ultrasonic impact treatment is for surface modification, determine whether alloying is necessary from the surface state of the metal material to be treated, or if necessary, the alloy component to be supplied, Next, after the processing temperature is determined from the phase diagram of the alloy, the ultrasonic impact processing conditions are determined from the relationship between the processing temperature and the processing pattern, and the combination of processing under heating or normal temperature is determined to perform the ultrasonic impact processing. (1) The metal material described in (1) How to set ultrasonic shock treatment conditions.

 (6) If the ultrasonic impact treatment is aimed at improving welding cracks, select the treatment temperature from the welding conditions for the target metal material and the state diagram of the target metal material, and then apply the ultrasonic impact from the relationship between the treatment temperature and the treatment pattern. It is characterized in that the processing conditions are determined and the ultrasonic impact treatment is performed by judging the combination of the temperature drop after welding and the ultrasonic impact treatment at room temperature. How to set sonic impact processing conditions. BRIEF DESCRIPTION OF THE FIGURES

 FIG. 1 is a diagram showing a flow of a method for setting ultrasonic shock processing conditions according to the present invention.

 Fig. 2 shows an example of an ultrasonic impact processing machine. Fig. 2 (a) is a schematic configuration diagram of an ultrasonic hammering impact processing machine used in the present invention, and Fig. 2 (b) is an ultrasonic impact processing machine used in the present invention. FIG. 2 is an enlarged view of a tip portion of the sonic shot peening impact processing machine. BEST MODE FOR CARRYING OUT THE INVENTION

 First, the ultrasonic impact processing in the present invention will be described.

 This ultrasonic impact treatment enables the following (a) to (d) and enables efficient processing of a wide area.

 (a) Multi-axial ultrasonic impact treatment promotes nano-crystallization.That is, it is difficult to obtain a nano-crystalline structure by uniaxial treatment. is necessary.

(b) By making the structure capable of controlling the temperature of the metal material surface, various characteristics of the surface layer obtained by ultrasonic impact treatment can be selected. Deformation is large but residual stress is small. Conversely, treatment at low temperature gives small deformation but large residual stress. Therefore, the degree of nanocrystallization and the state of the structure around the nanocrystal structure change, so that the processing conditions can be selected according to the required characteristics.

 (C) At least a structure capable of controlling the atmosphere of the treated surface, suppressing the formation of an oxide layer, achieving a good metal surface state, and further enabling the formation of an alloy layer. If the surface atmosphere is an oxidizing atmosphere, oxides generated on the material surface will be caught in the surface layer, causing surface defects and impairing the strength and corrosion resistance. By controlling the atmosphere, not only such a decrease in the surface material can be avoided, but also, by setting the atmosphere to a specific atmosphere, for example, a nitrogen atmosphere, it is possible to infiltrate the surface layer with nitrogen to improve the characteristics. Can also improve

(d) A structure capable of supplying an alloy component to the metal material to be treated, so that an alloy layer can be formed on the surface layer, that is, the metal component is applied to the place to be treated simultaneously with the ultrasonic impact treatment. Supplying powder, that is, providing an impact by using the pin itself as a specific metal material, and simultaneously supplying metal powder or small pieces of the pin to the surface of the material to be treated, and making the surface layer a desired alloy layer Can be. As a result, a new function can be added to the metal material surface.

In general, the above-mentioned ultrasonic impact treatment is generally performed as a micronization phenomenon in the surface layer of a metal material as a treatment thickness of 10 to 200 m, and a plastic deformation / molding depth direction range of 1 to 1 m. It is said to introduce up to 5 mm and compressive residual stress of about 1 to 3 mm. The present inventors have found through research that all of these phenomena are closely related to the processing temperature. In other words, since the phenomena and effects obtained in the processing temperature range are different from each other, setting the processing conditions in accordance with the target level of metal material reforming is directly possible with the above-mentioned ultrasonic impact processing. Get the full effect It can be demonstrated. The processing temperature range and the phenomena and effects obtained are described below, especially for steel, which is one of the most commonly used metal materials.

 ① V recrystallization region (about 850 ° C or more)

 Although the effect of miniaturization on the surface of the metal material is small, fine ferrite grains are generated by recrystallization miniaturization in the core and the toughness is increased, and the residual tensile stress due to fluidization during the solidification process is reduced on the plastic deformation Z-formed surface. Reduced and improved fatigue strength.

© ₁ unrecrystallized area (approximately 780 ° J ~ 850 ° 0

 In the core of the metal material, fine frit grains are formed by recrystallization refinement to increase toughness, and on the plastic deformation surface, particularly solidification cracks of the weld metal and cooling cracks can be prevented.

 ③ α · γ 2 phase region (approx.

 The crystal grains can be refined (nanosized) by the multiaxial treatment of the surface layer of the metal material, and at the same time, fine ferrite grains can be formed by recrystallization and refinement in the core, thereby increasing the toughness. In addition, on the plastic deformation molding surface, the fatigue strength can be improved because the welding toe can be efficiently molded. Furthermore, when high-strength steel is machined, it can be subjected to plastic deformation forming similar to mild steel at low temperatures.

 温度 Temperature range below A i point (approximately 400 ° C to 65 ° C)

 The crystal grains can be refined (nanosized) by the multiaxial treatment of the surface layer of the metal material, and at the same time, the structure can be refined by utilizing the reverse transformation behavior accompanying the decrease in the transformation temperature. In addition, on the plastically deformed Z-formed surface, the fatigue strength can be improved by efficiently forming the weld toe. Furthermore, on the weld surface, residual stress during multiple passes of welding and compressive residual stress due to cooling cracks can be reduced.

⑤Intensity expression area (below 400 ° C) The crystal grains can be refined (nanosized) by the multiaxial treatment of the surface layer portion of the metal material, and at the same time, the structure can be refined by utilizing the reverse transformation behavior accompanying the decrease in the transformation temperature. Also, plastic deformation can be expected to improve fatigue strength and reduce compressive residual stress.

 As described above, in the present invention, the treatment temperature is determined based on the required effects of the ultrasonic impact treatment, for example, the effects of improving the fatigue strength, modifying the surface, and improving the weld cracking in the target metal material. It is characterized in that conditions for ultrasonic shock processing are set. Of course, in the case of metal materials other than copper material as well, the above-described arrangement can be reasonably facilitated by utilizing the phase diagram obtained from the component composition, the temperature-strength relationship, and the like. These basic data can be easily collected in the literature including those at the textbook level, and can be applied to various metallic materials by utilizing the data in the method of the present invention. The procedure for setting the specific conditions will be described with reference to FIG.

 In Fig. 1, after determining the target of the metal material to be subjected to the ultrasonic impact treatment (working), it is necessary to determine what improvement effect should be given to the target by improving the fatigue strength, surface modification and welding cracking. Choose from improvements. For example, if the main purpose is to improve the fatigue strength, either the provision of the fatigue strength of the virgin material or the recovery of the fatigue strength of the existing material is used. Determine whether the treatment is inefficient and determine the treatment temperature from the temperature dependence of metal strength. On the other hand, in the case of existing materials, the appropriate processing temperature for recovery is determined from the phase diagram of the metal material. Next, for both cases, a work flow can be designed in which the ultrasonic impact processing conditions are determined from the relationship between the processing temperature and the processing pattern, and the processing under heating or normal temperature is determined and the ultrasonic impact processing is performed.

For example, when surface modification is the main purpose, alloying is necessary based on the surface condition of the target metal material, and if necessary, it should be supplied. After determining the gold component, and then determining the processing temperature from the target alloy phase diagram, the ultrasonic impact processing conditions are determined from the processing temperature-processing pattern relationship, and processing under heating or normal temperature is determined. A work flow for performing ultrasonic impact treatment can be designed.

 Furthermore, for example, if the main purpose is to improve weld cracking, after selecting the processing temperature from the welding conditions for the target metal material and the state diagram of the metal, determine the ultrasonic impact processing conditions from the processing temperature-processing pattern relationship, It is possible to design a work flow in which ultrasonic impact processing is performed by judging processing under heating or normal temperature.

Of course, in the ultrasonic shock treatment under heating, it is a matter of course that issues such as welding, heat source, temperature sensor, supply of metal components, and shield gas are taken into account. In addition, since the above-described ultrasonic impact treatment can provide an added effect by performing the treatment multiple times for each temperature range, the same processing or different processing may be appropriately performed multiple times in accordance with the above work flow. It is natural that the sonic impact treatment is performed. As an example of this ultrasonic impact treatment, for example, in a multi-pass welding process, the ultrasonic impact treatment is performed in a temperature range of 670 ° C to 750 ° C, and then the ultrasonic impact treatment is performed again at room temperature. As a result, a metal material having both high toughness and high fatigue strength can be obtained. In addition, in the repair welding of existing piers in use, the first pass bead is subjected to ultrasonic impact treatment at a temperature range of 850 ° C or higher to prevent hot cracking due to stress fluctuation. In subsequent lamination welding, ultrasonic impact treatment was performed in the temperature range of 400 ° C to 65 ° C to prevent lamellar tearing, and finally the toe after welding was completed was kept at room temperature. High fatigue strength can be imparted by ultrasonic impact treatment. Further, the surface of the steel material during or after use is subjected to ultrasonic impact treatment at the above-mentioned arbitrary temperature range to nanostructure the surface layer structure, and when the complementation of the alloy is required, the ultrasonic impact treatment is applied. It is necessary to supply alloy from outside. Regeneration can be achieved by adding necessary characteristics.

 Next, an ultrasonic impact machine used in the present invention will be described with reference to the drawings.

 Figure 2 (a) shows the outline of the equipment used for ultrasonic hammering impact processing, and (b) shows the outline of the equipment in which only the tip of (a) is changed to ultrasonic shot peening impact processing. FIG. In FIG. 2 (a), an ultrasonic hammering impact machine 1 has a transducer 2 that emits ultrasonic waves, and a cylindrical shape attached to the front of the transducer 2 and guides the ultrasonic waves generated by the transducer 2 to the tip. It comprises a wave guide 3 and a head 4 attached to the end of the wave guide 3, that is, the side facing the object to be processed. The head 4 has one or more holes 5 at its end, and a rod-shaped pin 6 inserted in the up and down direction of the hole 5, and between the upper end of the pin 6 and the end of the wave guide 3. It consists of a holder 9 that contains the provided space 8 and is housed.The holder 9 is detachably connected to the outer periphery of the wave guide 3 by an annular metal fitting 10, and can be replaced including the pin 6. It is configured as possible. The diameter, number, arrangement, material, shape, etc. of the pins can be changed as necessary.

 In addition, a resin cover 11 surrounding the outer periphery of the wave guide 3 with a gap provided therebetween is provided in the middle of the wave guide 3 to cool and lubricate the wave guide and the head having the vibrating section. The porous body 12 for holding the lubricant to be filled can be filled. In this case, an opening 13 is provided between the lower end of the cover 11 and the wave guide 3, and the lubricant coolant is supplied to the head 4 via the opening 13. However, this is not required. In addition, a water-cooled or air-cooled device may be provided to cool the transducer 2.

Transducer 2 converts electrical energy to ultrasonic energy For conversion, a magnetic or electric transducer can be used. The former can be increased in capacity and operate with high stability over a wide range of acoustic loads, but on the other hand are heavy and require cooling. The latter has a small capacity but is highly efficient, generates less heat, can reduce cooling, and is excellent in portability. However, on the contrary, the stability to the addition of sound is low. Therefore, a magnetic or electric transducer may be arbitrarily selected depending on processing conditions and purposes.

 The number of pins 6 stored in the head 4 may be one, but by arranging a plurality of pins in one or more rows, processing efficiency and processing area can be doubled. The pin 6 is generally vibrated in one axial direction, but the pin 6 itself may rotate or move in an arbitrary direction within the processing area. For example, when the pin 6 itself is to be rotated, a gear is attached to the root of each pin, and the motor is rotated 100 times Z seconds by the rotation driving force of an externally provided motor through the gear. In addition, it is also possible to wind an electromagnetic coil around each pin in the holder 9 and rotate it by electromagnetic force.

 When the transducer 2 emits ultrasonic waves, the generated ultrasonic waves are transmitted to the wave guide 3 connected thereto, and the velocity is denatured by the reduced diameter of the wave guide 3. The ultrasonic wave reaches the head 4 from the tip of the waveguide 3 and vibrates the pin 6 in contact therewith. Due to this vibration, the tip of the pin 6 strikes the surface of the object 14 to be subjected to impact processing. The processing conditions are preferably an amplitude of 20 to 60 μπι, a frequency of 15 kHz to 60 kHz, and an output of 0.2 to 1 kW.

On the other hand, the outline of the equipment used for ultrasonic shot peening impact processing is shown in Fig. 2 (b), which is partially enlarged, as shown in the ultrasonic hammering impact processing shown in Fig. 2 (a). Substitute for pin 6 in processing machines In addition, small particles 15 such as steel balls and cut wires or small particles 15 such as sapphires are stored in the head 4 by the ultrasonic waves emitted from the tip of the wave guide 3. The processed plate 8 is vibrated, the hard small-diameter steel material 15 in contact with the plate 8 is vibrated, and the surface of the object 14 to be processed is hit, thereby performing impact processing. The processing conditions may be the same as those when using the ultrasonic hammering impact machine described above. The material of the small particles of shots Biningu is, in the present invention using Safuaiya ball weighing approximately 7 mg, copper spheres mentioned above other, ultra copper balls, Serra Mi click Ssu, alumina (A1 ₂ 0 _3), Jirukonia (Zr0 _2), silicon nitride _{(S i 3 N 4),} S i C, S i O 2, Saiaro down like can be used. As the type of shot binning to be used, it is preferable to appropriately select and use the type, hardness, and ultrasonic oscillation power of the material to be treated. Further, it is more preferable that the diameter and area of the ultrasonic vibration plate are changed depending on the relationship between the small particles and the material to be treated. Industrial applicability

 According to the present invention, the temperature range of the ultrasonic impact treatment is selected according to the desired effect (improvement of fatigue strength, surface modification, and improvement of weld cracking) to be imparted to the target metal material. The desired effect can be obtained by performing this process, and a combined effect can be obtained by arbitrarily combining this treatment multiple times.Furthermore, the surface state of the steel material during or after use can be changed to a nanostructure. This has the effect that new characteristics can be added.

In addition, the surface of the stress-concentrated part where the fatigue strength is a concern in large-sized structures where the metal material to be treated is large and cannot be treated in a normal treatment furnace, should be repaired and treated periodically and repeatedly. In this way, the surface state of the steel material can be converted into a nanostructure to provide a property recovery effect. Change In addition, the effect of recovering the fatigue characteristics can be obtained by minimizing the deformation of the weld toe and by mainly converting the surface structure of the material to nano to eliminate the transition in the surface layer.

Claims

1. For the metal material to be treated, select one or more of the effects of fatigue strength improvement, surface modification, and weld crack improvement as the effects of the required ultrasonic impact treatment, and then After determining the ultrasonic impact treatment temperature in accordance with each of the above effects, setting conditions for the ultrasonic impact treatment, and finally determining an efficient combination of those treatments, How to set ultrasonic shock treatment conditions for materials.  2. If the ultrasonic impact treatment is intended to improve the fatigue strength of the newly-formed workpiece, determine whether the weld toe treatment is inefficient based on the metal strength of the newly-formed workpiece. Determines the processing temperature from the temperature dependence of the metal strength range, improves the toe shape by performing ultrasonic impact treatment at the temperature determined during the temperature drop process after welding, and further compressive residual stress The method for setting the ultrasonic impact treatment conditions for a metal material according to claim 6, wherein the ultrasonic impact treatment is performed again at room temperature under conditions effective to introduce the compressive residual stress, if it is desired to apply the ultrasonic impact treatment.  3. If the ultrasonic impact treatment is intended to improve the fatigue strength of the existing work, determine whether the weld toe treatment is inefficient based on the metal strength of the existing work. Determines the ultrasonic shock treatment temperature from the temperature dependence of the metal strength, heats it to the determined temperature, performs ultrasonic shock treatment to improve the toe shape, and applies compressive residual stress 2. The method according to claim 1, wherein the ultrasonic impact treatment is performed again at room temperature under conditions necessary for introducing the compressive residual stress. 4. If the ultrasonic impact treatment aims at recovering the accumulated fatigue of the existing workpiece, a process appropriate for the recovery of the transition accumulated due to the repeated stress from the state diagram of the metal material of the existing workpiece. After determining the temperature, The ultrasonic impact processing condition of a metal material according to claim 1, wherein ultrasonic impact processing conditions are determined based on a processing pattern relationship, and the ultrasonic impact processing is performed by judging a process under heating or normal temperature. How to set.  5. If the ultrasonic impact treatment is intended for surface modification, alloying is necessary based on the surface condition of the metal material to be treated, or if necessary, alloy components to be supplied are determined. After determining the processing temperature from the phase diagram of the alloy, determine the ultrasonic impact processing conditions from the relationship between the processing temperature and the processing pattern, determine the combination of processing under heating or normal temperature, and perform the ultrasonic impact processing. 2. The method for setting ultrasonic shock treatment conditions for a metal material according to claim 1, wherein:  6. If the ultrasonic impact treatment is intended to improve weld cracking, select the processing temperature from the welding conditions for the target metal material and the state diagram of the target metal material, and then use the ultrasonic impact The ultrasonic impact of the metallic material according to claim 1, wherein the treatment conditions are determined, and the ultrasonic impact treatment is performed by judging a combination of the temperature drop after welding and the ultrasonic impact treatment at room temperature. How to set processing conditions.