43 results about "Residual compressive stress" patented technology

A method for manufacturing high-strength, hydrogen-embrittlement-resistant bolts based on microsphere shot peening, and the bolts themselves, are disclosed. The manufacturing method includes: S1, cold heading and thread rolling of alloy structural steel billets to obtain bolt forming parts; S2, surface cleaning of the bolt forming parts, followed by overall surface peening with microspheres driven by high-pressure air; after overall peening, targeted strengthening peening treatment is performed on stress concentration areas such as thread roots, undercut grooves, and flange transition corners to obtain reinforced bolt parts; S3, the reinforced bolt parts are cleaned, dried, and phosphated to obtain finished bolt parts. This design, through a "overall + targeted" composite microsphere shot peening strategy, introduces a uniform residual compressive stress field and a micron-level fine-grained plastic deformation layer on the bolt surface, forming a thicker strengthening layer in stress concentration areas, significantly improving the fatigue strength and delayed fracture resistance of high-strength bolts, while ensuring uniform surface roughness and stable assembly friction coefficient.

The present application relates to injection molding machine template casting heat treatment technical field, disclose a kind of gradient composite heat treatment process for injection molding machine template casting, comprising: the injection molding machine template casting austenitizing heating of including nodular cast iron matrix and carbon fiber reinforced phase;Periodically modulate induction current in preset austenitizing temperature interval, utilize the thermal expansion difference of matrix and reinforced phase to generate alternating mismatch strain field, drive interface microzone local plastic deformation to induce dislocation multiplication, build dislocation strengthening interface layer, adjust interface stress to be residual compressive stress distribution;Injection molding machine template casting is implemented gradient cooling quenching, the present application utilizes interface dislocation strengthening mechanism to convert microcrack tensile stress into residual compressive stress, effectively passivates interface stress concentration effect, improves the fatigue resistance of casting under alternating load, cooperates and optimizes hardness gradient and inhibits interface peeling.

This invention relates to a method for predicting the wear performance of aluminum alloy surfaces using self-lubricating composite ultrasonic shot peening. The method first pre-treats the aluminum alloy surface, then textures the surface using laser processing, fills it with a self-lubricating material, and finally performs ultrasonic shot peening to form a mechanically interlocking structure that enhances the bonding strength of the filler layer. Ultrasonic shot peening creates a fine-grained strengthening layer and a residual compressive stress field on the substrate surface, significantly improving surface hardness and fatigue resistance. Simultaneously, this invention provides a wear performance prediction method based on ABAQUS simulation. By simulating the ultrasonic shot peening process using DEM-FEM coupling, a fretting wear model is constructed, and energy wear theory is used to predict the friction coefficient and wear rate. This method achieves four benefits for aluminum alloy surfaces: lubrication and friction reduction, mechanical interlocking, surface strengthening, and fatigue resistance. It can also predict wear performance in advance, guide process optimization, significantly improve R&D efficiency, and reduce experimental costs.

This application discloses a composite shot peening strengthening method for aerospace load-bearing structural components. The method includes dividing the shape-dependent regions or areas with high tensile stress distribution of the aerospace load-bearing structural components into regions and designing composite shot peening paths; designing process parameters for CNC mechanical microparticle shot peening and laser shot peening; performing CNC mechanical microparticle shot peening and laser shot peening; and finally, inspecting the shot peening strengthening quality of the aerospace load-bearing structural components. This application provides a composite shot peening strengthening method for aerospace load-bearing structural components, which can achieve composite shot peening strengthening of aerospace load-bearing structural components, increasing the residual compressive stress layer on the surface of the structural components while reducing surface roughness, effectively and quickly realizing composite shot peening strengthening of load-bearing structural components.

This invention discloses a lightweight manufacturing method for axles with built-in axle boxes, belonging to the field of rail transit axle technology. Based on the existing axle box-integrated alloy steel quenched and tempered axle design, this invention enlarges the central through-hole of the axle; then, the axle surface undergoes induction hardening treatment; followed by tempering treatment and grinding of the axle end faces and outer surfaces. This invention enables lightweight axle design and manufacturing, reducing the overall axle weight by 96.2 kg. The induction hardening treatment of the axle surface in this invention improves surface hardness and strength, enhancing resistance to external impacts and wear; the introduction of residual compressive stress on the axle surface can prevent or inhibit crack propagation; therefore, the method of this invention can achieve lightweighting while improving the axle's overall service life safety.

This invention discloses a manufacturing equipment and method for hot roughing universal joints used in metallurgical steel rolling. The equipment includes a worktable with four support legs at its bottom and a central control system at its top. It also includes a speed-changing support mechanism mounted on the top of the worktable, with two fixing mechanisms on the mechanism. The two fixing mechanisms respectively fix the universal joint and a flange. This supports the universal joint and the flange, enabling synchronous rotation and position adjustment, providing stable support for subsequent welding, straightening, and other processes. This device significantly improves welding quality by refining grains and dispersing impurities through multi-field coupling; avoiding surface damage through non-contact creep straightening; achieving micron-level straightening through ultrasonic rolling; forming a deep residual compressive stress layer to improve fatigue resistance; reducing human error through automated closed-loop control; adapting to various workpiece specifications; and significantly improving efficiency and reducing costs through integrated processing.

This invention discloses a method, device, terminal equipment, and storage medium for preventing tooth breakage based on laser peening, belonging to the field of gear surface strengthening technology. The method involves: acquiring the pulsed laser parameters and impact path of the gear to be treated during laser peening; providing an energy absorption layer at the root of the gear tooth, which is covered by a constraint layer; generating a laser scanning command based on the pulsed laser parameters and impact path, and sending the laser scanning command to a laser generator to control the laser beam to scan, so that the laser beam penetrates the constraint layer and irradiates the energy absorption layer; after being irradiated, the energy absorption layer absorbs laser energy to form plasma, and the plasma generates an inwardly propagating shock wave under the constraint of the constraint layer, inducing plastic deformation at the gear tooth root position and forming a residual stress layer on the surface of the gear tooth root. Therefore, by implementing this invention, the problem of insufficient depth of the residual compressive stress layer on the tooth root surface in the prior art can be solved.

The application discloses an ultrasonic rolling and dynamic stress real-time regulation integrated device and belongs to the technical field of ultrasonic rolling, which comprises a machine tool, a horizontal sliding table slidingly arranged along the length direction of the machine tool, and a sliding seat slidingly assembled on the top of the horizontal sliding table. The horizontal sliding cooperation of the mounting block and the sleeve pipe, in combination with a special counterweight mechanism composed of a limiting ring, a counterweight ring, a plug rod and a supporting plate, can provide constant and accurately adjustable static pressure for the rolling process. In addition, the adaptability of the limiting ring from top to bottom with the gradual change of the inner diameter and the outer diameter of the counterweight ring enables the automatic increase and decrease of the counterweight by controlling the lifting height of the guide block two, without the need for complex manual operation. The application solves the problems of over-processing of the convex area and insufficient processing of the concave area caused by the linear correlation between the traditional spring elastic force and the deformation amount, ensures the uniform distribution of the residual compressive stress on the workpiece surface, significantly improves the strengthening consistency of ultrasonic rolling, and adapts to complex working conditions with different topography errors and material hardness.

Provided are a hard coating film which has a new composition and has excellent wear resistance and anti‑adhesion properties to a wide range of workpieces, and a tool coated with the hard coating film. A hard coating film according to the present invention has features such as improved wear resistance, high hardness, and excellent lubricity, owing to not only refinement of crystal particles in a composition A and a composition B but also to the fact that the crystal structures thereof have a cubic rock salt type structure. In addition, the hard coating film includes interfaces AB at which layers composed of the composition A and layers composed of the composition B are in contact with each other. Since each of the layers composed of the composition A is adjacent to the corresponding layer composed of the composition B, AlCrN particles having a cubic rock salt type crystal structure are surrounded by a thin BNx structure phase, whereby the hardness of an AlCrN layer that is a characteristic of the composition B can be increased while reducing the compressive residual stress of an AlCrBN layer that is a characteristic of the composition A. Therefore, the relationship between the hardness and the toughness of the coating film can be controlled, and the wear resistance can be further improved.

This application discloses an in-situ non-destructive method for repairing and reinforcing fatigue cracks in steel structures based on laser technology, relating to the field of steel structure building technology. The method includes the following steps: initial flaw detection of the area to be repaired in the steel structure to obtain the crack size of the fatigue crack; cleaning the area to be laser-repaired and reinforced; scanning and repairing along the crack trajectory using laser remelting technology to allow the fatigue crack to heal naturally; secondary flaw detection of the remelted repair area after laser remelting; if the test is qualified, the repair process is completed; if the test is unqualified, the residual crack depth is obtained, and the following steps are continued; reinforcing auxiliary materials are printed on the surface of the steel structure using laser cladding technology to form a cladding layer covering the remelted repair area; a residual compressive stress layer is introduced onto the surface of the cladding layer. This application eliminates the need for beveling and milling of the original steel structure, enabling direct repair of fatigue cracks, and also allows for the addition of external reinforcing auxiliary materials to effectively integrate with the original steel structure to achieve the reinforcement purpose.

The application provides a 2Cr13 forging method for improving corrosion fatigue resistance of a last-stage blade of a steam turbine, which can realize grain refinement, carbide distribution optimization, surface integrity improvement and favorable residual compressive stress introduction by optimizing temperature gradient between forging heats and inserting surface treatment and heat treatment procedures in the whole forging process, so as to systematically improve service performance of the blade under corrosion-fatigue coupling conditions. The 2Cr13 forging method for improving corrosion fatigue resistance of a last-stage blade of a steam turbine comprises the following steps: top forging, first heat forging of a blank; the temperature of the first heat forging is 1135-1145 DEG C; pre-forging, second heat forging of the first intermediate blank after the top forging, the temperature of the second heat forging is 1125-1135 DEG C, and the second heat temperature is less than the first heat temperature and forms a gradient temperature difference of 5-20 DEG C; finish forging, third heat forging of the second intermediate blank after the pre-forging, the temperature of the third heat forging is 1030-1040 DEG C, and a blade forging piece is obtained.

The application discloses a process control method for mechanical shot peening and deep rolling composite strengthening of AISI 4340 ultra-high-strength steel, and belongs to the technical field of metal surface strengthening. The application is aimed at the problems that surface deformation strengthening of AISI 4340 ultra-high-strength steel is difficult at normal temperature, damage control is difficult, and existing composite process parameters are wide, equipment is complex, and cost is high. The application adopts mechanical shot peening and deep rolling step-by-step composite, matches key process parameters such as shot peening strength, rolling force, feed amount and rolling pass, induces a continuous gradient structure with significantly increased depth on the surface layer of AISI 4340 ultra-high-strength steel, and significantly reduces surface roughness, improves residual compressive stress and increases surface layer dislocation density. The experimental results show that the fatigue life of the sample is significantly improved after the method is processed, and the crack initiation on the surface of the component is effectively inhibited. The application has low cost and is easy to industrialize, and is suitable for anti-fatigue manufacturing of key load-bearing components in aerospace.

The application discloses a kind of low-temperature vacuum pressing preparation no-coating zirconium alloy anticorrosion pipe fittings and method thereof, belong to material surface treatment technical field, the method is in the vacuum softening annealing process of no-coating industrial grade zirconium alloy seamless pipe fittings Synchronous implementation ironing pressure, specifically at 400~550 under vacuum softening annealing 2h, ironing pressure processing is carried out simultaneously, ironing pressure vibration amplitude 15~25, feed 750~850, ironing pressure cutter head temperature is 400~550, workpiece rotating speed 100~800.The method is in the vacuum softening annealing process by ironing pressure optimization no-coating industrial grade zirconium alloy seamless pipe fittings surface structure and introduce residual compressive stress, significantly improve its surface density and oxidation resistance, so that no-coating industrial grade zirconium alloy seamless pipe fittings in chemical corrosion environment greatly enhance the service life and safety.

The application discloses a heat treatment process of a firing pin of a nail gun and the firing pin. The thickness distribution of a plating layer is accurately controlled according to a bevel angle, the gradient diffusion mechanism of carbon elements in a heat treatment process is utilized, the hardness gradient distribution from a tip to a root is formed in a bevel area, the differentiated requirements of different areas on hardness and toughness are met, the included angle between a projectile jet flow and the normal direction of a bevel impact surface is controlled, the projectile impact energy is effectively transmitted along the direction of the geometric characteristics of the bevel, the surface residual compressive stress distribution is optimized, the interface bonding strength of the gradient hardened layer is enhanced, the crack initiation and expansion are inhibited, the accurate regulation of the microstructure and the residual stress field of the bevel area is realized, the thermal stress inhomogeneity caused by the geometric shape difference in the heat treatment process is effectively compensated, the stress distribution state of the bevel angle firing pin under high-frequency impact load is obviously improved, and the stress concentration problem caused by the performance mutation in the traditional process is avoided.

To alleviate stress exerted on a thread portion of a threaded steel pipe or tube during use to prevent fatigue fracture, there is provided a threaded steel pipe or tube having a female thread portion on an inner peripheral surface of at least one end, wherein a maximum value of residual compressive stress at a position of 0.4 mm in a depth direction from a thread bottom of the female thread portion is 100 MPa or more and less than or equal to tensile strength of a material of the threaded steel pipe or tube.

This invention discloses an ultrasonic-assisted roller pressing laser deposition additive manufacturing fatigue performance control system, belonging to the field of additive manufacturing composite process technology. The system includes a machine bed, with a rotating module mounted on the bed for clamping and driving the substrate shaft. The ultrasonic-assisted roller pressing laser deposition additive manufacturing module integrates a laser cladding device and an ultrasonic roller pressing device, both mounted on a feed module via a connecting plate and a fixed frame. The feed module drives the composite module to move horizontally. This invention applies ultrasonic vibration and mechanical roller pressing to the high-temperature deposited layer simultaneously with laser cladding, utilizing the ultrasonic cavitation effect to refine grains and eliminate porosity, while simultaneously introducing residual compressive stress. This system achieves microstructure optimization and active fatigue performance control during the additive manufacturing process, significantly improving the mechanical properties and reliability of the formed components.

This invention discloses a heat treatment process for structural steel used in wind turbine towers, comprising the following steps: heating the steel plate as a whole to 880~920℃, austenitizing and holding at that temperature for 1.0~2.0 min / mm plate thickness; dividing the steel plate into three virtual regions—a surface region, a transition region, and a core region—symmetrically on both sides along the thickness direction, and cooling each region independently; heating the steel plate to 450~550℃, holding for 1~3 hours, and then slowly cooling it in the furnace to below 300℃ before air cooling. This invention employs gradient zone cooling of the steel plate, achieving "one steel for three uses" under the conventional Q345 / Q355 composition system simply by differentiating heat treatment parameters. This avoids the complexity of procuring different grades of steel for different tower sections. Furthermore, the gradient transition region eliminates the interface of abrupt performance changes, and the residual compressive stress field introduced by the rapid cooling of the surface layer significantly improves the hardness, fatigue limit, and elongation after fracture of the steel plate.

This invention relates to the field of steel ball manufacturing technology, and particularly to a high-efficiency quenching process for steel ball manufacturing. The process sequentially includes raw material pretreatment, segmented preheating, induction heating, three-dimensional flow-guided quenching, two-stage tempering, surface residual compressive stress strengthening, online detection, and quenching medium circulation regeneration. This ensures that the internal structure of the steel ball is fully austenitized before entering the quenching tank. A high-speed circulating polymer aqueous solution quenching structure is used, allowing the steel ball to achieve a rapid and uniform cooling rate under the action of three-dimensional eddies, effectively reducing quenching cracks and microstructure inhomogeneity. Two-stage tempering combined with high-pressure rolling strengthening forms a deep compressive stress layer on the surface. Through closed-loop control of temperature, flow rate, vacuum degree, and data acquisition, this process significantly improves the hardness consistency of the steel ball, reduces the probability of quenching deformation and defects, and produces products with high precision, dense microstructure, and long fatigue life. It overcomes the problems of high energy consumption, low efficiency, and unstable quality associated with traditional intermittent quenching.

The application relates to an ultrasonic impact strengthening device and method based on reverse elastic preloading, and belongs to the technical field of metal surface treatment. The device comprises a rotary driving device for driving a shaft workpiece to rotate around an axis thereof; a clamping swing device for clamping the shaft workpiece; the clamping swing device comprises a base plate, a first swing assembly, a second swing assembly, a first clamping assembly and a second clamping assembly; a reverse pre-bending device for applying a reverse pre-bending load to both ends of the shaft workpiece; the reverse pre-bending device comprises a horizontal telescopic driving mechanism, a tension sensor, a first pull rod and a second pull rod, the first pull rod is used for pulling the first clamping assembly, and the second pull rod is used for pulling the second clamping assembly; and an ultrasonic impact device for performing ultrasonic impact strengthening on the shaft workpiece. The application can apply a reverse pre-bending opposite to the ultrasonic impact direction to the shaft workpiece, obtain a better residual compressive stress field, improve the overall stability of a surface strengthening layer, and prolong the fatigue life.

This invention relates to a fracture-resistant worm gear for RV reducers and its surface strengthening method. The outer diameter of the overtravel zone is equal to the root circle diameter of the helical tooth. A large fillet is formed between the helical tooth and the overtravel zone. The end of the overtravel zone and the journal form a flared section with gradually increasing radial dimensions. The outer surface of the flared section is a concave arc surface formed by rotating an elliptical arc. Both the outer surface of the flared section and the outer surface of the overtravel zone are rolled to form a reinforced outer surface layer. This reinforced outer surface layer includes a mechanically plastically deformed layer and a residual compressive stress layer beneath the plastically deformed layer. The fact that the outer diameter of the overtravel zone is equal to the root circle diameter of the helical tooth completely eliminates the traditional right-angle step and removes a major stress concentration source. The large fillet design significantly reduces the stress concentration factor and greatly inhibits fatigue cracking. The flared section forms a streamlined, expanded-diameter transition zone, improving the worm gear's resistance to bending fatigue. Controllable plastic deformation forms a reinforced outer surface layer, increasing surface hardness and strength.

This invention proposes a composite surface treatment and heat treatment process for a wheel hub adapter, belonging to the technical field, and includes the following steps: Step 1, workpiece pretreatment; Step 2, multi-stage temperature-controlled tempering heat treatment; Step 3, laser shock peening pretreatment; Step 4, graded controllable gas nitriding treatment; Step 5, preparation of a surface nano-protective layer. This invention proposes a composite surface treatment and heat treatment process for a wheel hub adapter, forming a gradient structure of "high toughness in the core, high hardness in the surface layer, and corrosion resistance" through multi-stage tempering heat treatment, laser shock peening, graded nitriding, and nano-coating. The core hardness reaches 34-38 HRC, and the impact energy is ≥65 J; the residual compressive stress depth of the surface layer reaches 1.2 mm, with a peak value of -700 MPa; the nitrided layer depth is 0.35 mm, and the hardness reaches 850 HV. 0.3 The nano-coating has a friction coefficient ≤0.12 and withstands a 600-hour salt spray test. The synergistic effect of each process significantly improves overall service performance.

This invention provides a non-contact, adjustable alternating magnetic field-eddy current coupled laser shock strengthening device and method for improving hydrogen embrittlement resistance. The device includes a laser shock strengthening unit, a magnetic field generating unit, a driving unit, and a position adjustment unit. The magnetic field generating unit has alternating N and S pole permanent magnets, which are driven to rotate by the driving unit. This induces an alternating magnetic field and closed eddy currents within the metal workpiece. The magnetic field strength, eddy current density, and temperature rise are synergistically controlled by adjusting the air gap and rotation speed. This invention couples a multi-directional alternating electromagnetic field during laser shock, promoting the activation of multiple slip systems and dislocation dispinning, improving the surface microstructure uniformity and residual compressive stress distribution, effectively inhibiting hydrogen intrusion and enrichment, delaying the initiation and propagation of hydrogen-induced cracks, and improving the workpiece's resistance to hydrogen embrittlement. The device has no contact electrodes and is suitable for complex curved surfaces and large-area workpieces.

This invention relates to the field of metal pressure processing, specifically to a precision drawing method for reducing residual stress in wire. It includes surface pretreatment, initial drawing, intermediate anti-tension drawing, and final precision drawing steps. The process is carried out in series using a continuous wire drawing machine. The key is that the reduction rate of each pass decreases progressively, and the final pass uses a small reduction rate of 3%–5% combined with a large working cone angle of 14°–18°. Its core is to confine plastic deformation to the surface layer of the wire by utilizing the large cone angle and small reduction rate, while leveraging the elastic restraint of the deep core metal to introduce microscopic residual compressive stress into the surface layer. This invention effectively solves the problems of warping and stress corrosion cracking in downstream wire processing by transforming the residual tensile stress accumulated in traditional processes into compressive stress, significantly improving forming quality while maintaining high tensile strength.

The present application relates to a kind of orifice chamfering reinforcement forming tool and method thereof.It includes support seat, conical surface pressure head, roller and cage;The orifice chamfering reinforcement forming tool is used to roll the orifice edge into target orifice chamfer;Support seat lower part is support platform, and support shaft is vertically extended on support platform;Conical surface pressure head is rotary body, and central shaft hole is opened, and the lower end of the conical surface pressure head forms outer conical surface, and the conical surface angle of outer conical surface is identical with the chamfer angle of target orifice chamfer;Ring groove is opened on the outer conical surface, and cage and multiple rollers are arranged in the ring groove, and the spacing between the roller is kept under the limitation of the cage, while rolling in the ring groove in ring direction.The beneficial residual compressive stress is generated in the surface layer and subsurface of orifice chamfer after rolling extrusion, and the hardness of metal surface, the strength of material and surface finish are improved.

This invention relates to the field of grinding technology, and discloses a precision grinding device and method for a fatigue-resistant special steel spindle for aircraft. The device includes: multiple coaxially spaced positioning components with placement grooves; a moving component that drives a connecting seat to move axially, with a vertical telescopic component mounted on the connecting seat via a bracket; a grinding wheel assembly connected to the output end of the vertical telescopic component via a strain gauge force sensor; a control component that adjusts the extension and retraction of the vertical telescopic component based on the force sensor signal and a PID algorithm to maintain constant contact pressure, adapting to minor ellipticity or local protrusions of the spindle, avoiding impact scratches and stress concentration; and also includes an infrared thermal imager, an electrolyte spraying device, and a laser alignment device to achieve constant pressure flexible grinding, active alignment, and temperature-graded protection, effectively preventing surface burns and micro-cracks, and inducing beneficial residual compressive stress.

The present application relates to the technical field of surface strengthening technology of sports equipment, in particular to a kind of ice skate blade multi-field composite strengthening method.The method comprises the following steps: adjusting laser head, so that laser beam covers the top surface and chamfer of ice skate blade;adjusting ultrasonic rolling device, so that rolling head is located at both sides of ice skate blade;according to the material properties of ice skate blade, determine the required laser energy and rolling force;while laser shock peening is carried out, double-sided rolling ultrasonic rolling strengthening is carried out on the side surface of ice skate blade.Through laser shock peening on the top surface of blade and double-sided rolling ultrasonic rolling, deformation and layer cracking can be avoided, at the same time, multiple energy fields are combined, the dynamic yield strength of the material is reduced, the material is more prone to plastic deformation and strengthening effect, deeper residual compressive stress is achieved, and the strengthening effect of the chamfer part is particularly beneficial.

This invention discloses a wide-range gradient controllable residual stress calibration block and its preparation method, belonging to the field of stress calibration technology. The preparation method includes processing a carburized steel substrate into a blank and sequentially performing carburizing and quenching, shot blasting, grinding to remove the surface oxide layer, and shot peening. The shot-peened blocks are divided into at least two groups, and tempered in different temperature ranges to obtain blocks with different residual compressive stress levels. The different temperature ranges are selected from at least two of the following: 50-150℃, 150-250℃, and 350-450℃. At least a portion of the tempered blocks undergoes surface corrosion treatment to remove the deformation layer of a predetermined depth and fine-tune the residual stress value. Finally, the blocks are rust-proofed and stored. This invention solves the problems of existing calibration blocks having single stress values, poor stability, and short shelf life. It achieves the acquisition of stable calibration blocks with different stress gradients within the same material batch.

The application discloses a kind of electric locomotive complex shape skin laser impact forming device, including solid laser, laser controller, laser ranging sensor, part clamping robot, part clamping robot control system, water spraying robot, water spraying robot control system, high-speed laser profiler detection device, first forming plate fastening arc clamping plate, second forming plate fastening arc clamping plate, third forming plate fastening arc clamping plate, data acquisition card, computer integrated control system, laser focal point indicator and forming simulation system.The application also discloses a kind of electric locomotive complex shape skin laser impact forming method, based on laser impact forming numerical simulation plug-in, corresponding forming data is obtained;Different forming areas are clamped and different process parameters are applied respectively, to realize excess-free laser impact forming;Finally, the adhesive remaining on the surface of the formed skin is removed.The application accurately forms the complex shape skin of locomotive, and forms residual compressive stress with a certain depth.

The application discloses high-speed train axle steel with high corrosion fatigue resistance and a stable residual stress layer, which is prepared by adopting a high-silicon-medium-chromium-rare earth composite alloying design and combining an innovative heat treatment process of incomplete quenching and two-stage tempering, so that the prepared axle steel has excellent conventional mechanical properties, Rm is greater than or equal to 750 MPa, Rp0.2 is greater than or equal to 600 MPa, and -40 DEG C KV2 is greater than or equal to 60 J, has super-high corrosion fatigue resistance, and has a beneficial surface residual compressive stress, and thus can meet the use requirements in a corrosive environment such as a coastal area and a high-humidity environment.

The application relates to the field of bearing machining, and particularly discloses a machining process for a bearing outer ring, which comprises the following steps: S1. pretreatment; S2. surface nanocrystallization treatment; S3. rough grinding; S4. fine grinding; S5. superfinishing; and S6. cleaning. The surface nanocrystallization treatment is added before grinding, the raceway surface layer is subjected to severe plastic deformation through high-speed projectile impact, a gradient nanocrystalline structure layer which is gradually changed from the surface nanocrystalline to the coarse grain in the center is formed, the structure layer can improve the surface hardness and strength, reduce the subsequent grinding force and grinding heat, inhibit thermal damage and organizational phase change, deep stable residual compressive stress is introduced into the surface layer, the tensile stress generated during grinding is offset, the raceway is finally in a beneficial compressive stress state, and therefore, a high-hardness and low-damage high-quality surface layer is obtained, and the bearing matching precision, running stability and service reliability are improved.