966 results about "Heat-affected zone" patented technology

The invention relates to the technical field of welding processing, and discloses a dissimilar metal welding joint temperature field optimization control method and system. Real-time temperature field scanning is conducted on the dissimilar metal welded joint, image segmentation processing is conducted on a temperature field image obtained through scanning, temperature data of a weld joint area, a heat affected area and a base metal area are extracted, and whether the temperature gradient exceeds a preset threshold value or not is judged; aiming at an area with non-uniform distribution of heat input quantity, analyzing the performance of the welding joint under the combined action of thermal stress and mechanical stress, obtaining the difference between residual stress distribution and plastic deformation capacity, and analyzing a stress concentration area by combining with the yield strength of the material; and a mapping relation between the welding process parameters and temperature field distribution is established, and a welding process parameter adjustment prediction model is obtained through historical welding process parameters and corresponding temperature field data training in combination with heat flux density distribution. The problems of uneven heat input, stress concentration and the like in dissimilar metal welding are effectively solved, and the welding quality and efficiency are improved.

The invention discloses a weldment welding seam automatic detection method and device based on machine vision, and relates to the technical field of machine vision intelligent detection. The weldment welding seam automatic detection method and device based on machine vision comprises the steps that S1, surface images and forming feature data of a weldment are collected and preprocessed to construct a standardized image feature data set; s2, the boundary clearness of the weld joint is evaluated by combining the edge strength and the contour coherence, and the main contour extraction range is dynamically adjusted; s3, analyzing abnormal focusing characteristics of the candidate area, and adjusting a defect labeling range and a detection priority; and S4, integrating the boundary definition and the abnormal focusing features, analyzing the structure abnormality, and dynamically controlling and verifying a resource allocation strategy. The problems that in the weldment detection process, obvious light reflection and texture blurring phenomena exist in a heat affected area at a weld joint, a traditional image enhancement and edge extraction algorithm is difficult to stably recognize microdefects, and the credibility of a detection result is reduced are solved.

The invention discloses a welding path planning method based on machine vision, and relates to the technical field of welding robotics.The method comprises the steps that sample data of various groove types are collected, classified and stored, a groove type database is established, and an extraction condition template is defined; groove section data are obtained through the machine vision technology, a three-dimensional model is constructed after grouping, welding seam, material and heat affected zone characteristics are analyzed, a welding sequence principle is determined, and a comprehensive welding path is generated; key parameters in the welding process are monitored in real time, an early warning mechanism is set, and the optimal path is dynamically adjusted; updating a database according to the path planning efficiency value, comprehensively analyzing candidate paths, and recommending an optimal welding path; the extraction condition template is dynamically adjusted, the precision, adaptability and efficiency of welding path planning can be improved, and the welding quality and stability are ensured; and a plurality of different cross section data are analyzed, the comprehensive welding path is determined, and various different cross section data characteristics can be met at the same time.

The invention relates to the technical field of automatic welding control, and particularly discloses a multi-station automatic welding cooperative control method for electric iron accessories, which realizes full-closed-loop accurate control of a welding process through multi-sensor data fusion and an intelligent optimization algorithm. According to the method, an infrared thermal imager, an acoustic emission sensor and an ultrasonic thickness measuring device are adopted to collect molten pool temperature field, sound wave frequency spectrum and fusion depth data in real time, after feature extraction, the data are input into a multi-target optimization model, and a Pareto optimal solution set is generated with the fusion depth, the width of a heat affected zone and phase change latent heat as optimization targets; dynamically adjusting a segmented welding-back path and process parameters on the basis of an optimization result, and triggering model iterative correction through ultrasonic online monitoring; the central control unit adopts space voxelization monitoring and a three-level collision avoidance strategy to coordinate operation of the multiple mechanical arms, and collision emergency protection is achieved in combination with flexible pressure sensing.

The invention discloses a water jet assisted laser-electrochemical combined machining method which comprises the following steps: pre-treating a nickel-based superalloy to be machined, and fixing the nickel-based superalloy on a machining table; a machining area is positioned, parameters of water jet assisted laser and electrochemical machining are set, so that during laser machining, water jet cools the machining area and removes slag, and an electrolyte does not affect a non-machining area; meanwhile, water jet assisted laser and electrochemistry are started to machine the nickel-based superalloy, and the machining state is monitored in real time; and after composite machining is completed, the nickel-based high-temperature alloy is cooled. By accurately setting laser, water jet and electrochemical machining parameters, the efficient synergistic effect of the laser, water jet and electrochemical machining parameters in a machining area is ensured, the machining precision and the surface quality are effectively improved, the defects of heat affected zones, microcracks, recast layers and the like are remarkably reduced, and the machining quality is improved. And meanwhile, corrosion to a non-machining area is reduced through the mode of spraying the electrolyte in a pulse mode.

The invention discloses a method for homogenizing a microstructure of a low-temperature high manganese steel welding heat affected zone by using pulse current, and belongs to the technical field of welding and postweld heat treatment of high manganese steel for liquefied natural gas (LNG) storage and transportation. The treatment method comprises the following steps: (1) sampling a heat affected zone of the low-temperature high-manganese steel welded joint with microstructure gradient distribution; (2) the low-temperature high manganese steel welding heat affected zone sample is subjected to pulse current treatment at the room temperature, the pulse frequency ranges from 0.6 kHz to 6 kHz, the pulse width ranges from 0.2 ms to 6 ms, the current density ranges from 20 A / mm < 2 > to 200 A / mm < 2 >, and the treatment time ranges from 5 min to 120 min; and (3) grinding and polishing the sample, observing and analyzing the element distribution state in the heat affected zone, and quantitatively representing the grain boundary structure characteristics. According to the method, atomic diffusion, dislocation slippage and grain boundary migration of the low-temperature high-manganese steel welding heat affected zone can be promoted by applying the pulse current, redistribution of segregated atoms and dislocations in grains and at grain boundaries is rapidly achieved, and then the purposes of improving the microstructure uniformity of the low-temperature high-manganese steel welding heat affected zone and improving the impact toughness of the low-temperature high-manganese steel welding heat affected zone are achieved. The method is easy to operate, short in treatment time, environmentally friendly and particularly suitable for postweld treatment of low-temperature high manganese steel parts.

The invention relates to the field of pipeline welding, in particular to a prediction model construction method, system and equipment of a heat affected zone and a prediction method. The method comprises the steps that phase change parameters of a metal microstructure phase change model are corrected based on a thermal simulation test; building a heat affected zone microstructure finite element prediction model according to the circumferential weld simulation calculation finite element model; and correction is carried out based on a heat affected zone hardness test and a small punch test correlation parameter correction method, and the heat affected zone strength prediction model is trained by using the expansion database to obtain the pipeline welding joint heat affected zone strength prediction model. Based on a material performance determination test, a finite element model construction method and a finite element model expansion database mode, the accuracy of the heat affected zone strength prediction model is greatly improved, the research cost is reduced, the prediction from a microstructure to macroscopic performance is realized, and the method is suitable for popularization and application. And the defect that the softening mechanism of the hot area material cannot be clarified by traditional macroscopic mechanical property test analysis is overcome.

The invention relates to the technical field of welding platforms, in particular to a multifunctional welding process experiment platform and a process optimization system.The process optimization method comprises the following steps that a welding process setting module is constructed, and a welding mode, a groove type and a heat input scheme are preset; outputting the initial process configuration parameter set to drive a welding execution unit to perform automatic welding operation according to the initial process configuration parameter set; extracting a multi-dimensional process response vector including a stability index, metal fusion depth distribution and a heat affected zone expansion degree; outputting a welding seam grade result according to a preset quality grading standard, and generating a feedback identifier; and after updating, inputting to the step S2 again to form closed-loop optimization control. According to the method, digital modeling and evaluation of key indexes such as the welding stability, the fusion depth and the heat affected zone are achieved, and the problem that a traditional process depends on visual inspection and experience judgment is solved.

The invention relates to the technical field of laser processing, in particular to a multi-beam intelligent focusing invisible laser cutting device and method. A multi-beam intelligent focusing invisible laser cutting device comprises a laser source, a beam splitting module, a focus control module and a wafer scanning module. The beam splitting module comprises a beam expanding device, a reflecting mirror, a diffraction light splitting device and a collimating mirror group; the laser source emits a light beam to irradiate the beam expanding device; the beam expander is located between the laser source and the reflector; multi-line and multi-layer simultaneous cutting can be achieved through single scanning, repeated positioning is not needed, the wafer invisible cutting efficiency can be greatly improved, and the cutting efficiency is improved by several times compared with a traditional single-layer process. Energy is dispersed by using ultrafast laser and multiple light beams, and the influence of a heat affected zone on the wafer is reduced. The device can adjust different line laser focus positions in real time, and is compatible with different material thicknesses and structures.

The invention belongs to the field of steel rail manufacturing, and discloses a method for improving the impact toughness matching performance of a dissimilar material steel rail welding joint. The method comprises the following steps: carrying out first-stage cooling on a welding joint formed by welding the eutectoid pearlite steel rail and the bainite steel rail; carrying out full-section normalizing heating on the welded joint; the welding joint is subjected to second-stage cooling, a heat affected zone on one side of the heat treatment type eutectoid pearlite steel rail is cooled to 350-400 DEG C at the cooling rate of 4.0-7.0 DEG C / s, and a heat affected zone on one side of the hot rolling type bainite steel rail is cooled to 290-315 DEG C at the cooling rate of 2.0-3.0 DEG C / s; the welding joint is heated to a bainite transformation temperature interval for isothermal treatment; and naturally cooling the welding joint in an air environment. According to the method provided by the invention, the room-temperature impact toughness of the heat affected zone on one side of the hot-rolled bainite steel rail can be obviously improved, so that the performance of the hot-rolled bainite steel rail is better matched with that of a hot-rolled bainite steel rail base material.

The invention belongs to the technical field of chip processing, and discloses a wafer laser cutting device based on chip processing, which comprises a vibration mechanism, the vibration mechanism comprises four sliding blocks, the interiors of the sliding blocks are fixedly connected with first motors, and the first motors are rotatably connected with cams; through cooperation of the cam, the clamping plates and other structures, the laser cutting effect of the wafer is improved, the first motor is started to enable the wafer clamped among the four clamping plates to generate slight vibration in the vertical direction, the slight vibration promotes micro movement of a material in the laser cutting process, better interaction between a laser beam and the material is facilitated, and the laser cutting efficiency is improved. A more uniform and smoother cutting face is achieved, the vibration effect can accelerate the melting or crushing process of materials, the cutting time is shortened, the cutting efficiency is improved, meanwhile, vibration can accelerate airflow on the surface of a wafer, a certain heat dissipation effect is achieved, local overheating of the materials is reduced, expansion of a heat affected zone is avoided, and the flatness of the cutting edge is improved.

The invention belongs to the technical field of laser welding, and discloses a multi-parameter cooperative control laser welding method and system.The method comprises the steps that a laser energy control model is established based on material strength-thickness-gap ternary coupling, and the output power of an optical fiber laser is controlled; coaxial three-layer gradient gas is adopted for protection of a welding area, preheating before welding and double-temperature-zone gradient annealing after welding are adopted, the output power of an optical fiber laser and the three-layer gradient gas protection flow are regulated and controlled in real time through combination of multiple sensors and a control algorithm, the temperature of a heat affected zone is monitored in real time, and a cooling nozzle is controlled for cooling. And continuous parameter optimization is achieved through machine learning, and multi-parameter control laser welding is achieved.

The invention belongs to the technical field of hard and brittle crystal material micropore machining, and particularly relates to an ultra-precision micropore multi-energy field coupling machining method and system.The method comprises the steps that the laser pulse frequency and power are set according to the workpiece material type and the micropore depth-diameter ratio, and a laser focus is positioned at the inner hole bottom of a workpiece; a modified structure extending in the axial direction of a hole is formed by controlling matching of a light spot and a hole diameter and the movement track of the light spot, in the machining process, a plasma nozzle and laser coaxially move, a modified area is removed in real time, a heat affected zone and the hole shape taper are restrained, meanwhile, vibration is applied to a workpiece through an axial ultrasonic vibration device, and machining precision is improved. And chip discharge is promoted, and stress and crack generation are reduced. The problems of serious thermal damage, poor hole shape precision, low machining efficiency and high energy consumption in the micropore machining process in the prior art are solved, and high-quality and high-precision machining of the high-depth-diameter-ratio micropore of the hard and brittle transparent crystal material is achieved.

The invention discloses a connecting method of an FGH99 double-radial-plate turbine disc based on a nanocrystallization high-entropy alloy middle layer, and belongs to the technical field of welding. A high-entropy alloy middle layer is adopted, nanocrystallization treatment is combined to optimize a microstructure, the nanocrystallization high-entropy alloy middle layer is arranged between an upper FGH99 double-radial-plate turbine disc and a lower FGH99 double-radial-plate turbine disc, diffusion connection is conducted in a vacuum diffusion welding furnace, and the welded FGH99 double-radial-plate turbine disc is obtained. Low-damage solid-phase diffusion bonding is achieved at the welding temperature lower than the solid solution temperature of base metal; meanwhile, the nanocrystallization interlayer structure promotes element diffusion, the diffusion welding period can be greatly shortened, the problems of grain coarsening and performance degradation of a heat affected zone caused by long-time heat preservation in a traditional technology are solved, the technical bottleneck of cooperative regulation and control over the strength and toughness of a high-temperature alloy complex component connection interface is broken through, and the application prospect is wide. And a high-reliability solution is provided for efficient manufacturing of the double-radial-plate turbine disc of the aero-engine, and the double-radial-plate turbine disc is particularly suitable for the long-service-life service requirement under the working conditions of extreme high temperature and cyclic loads.

The utility model relates to the technical field of battery manufacturing, and particularly discloses a battery, a battery pack and a power utilization device. The battery comprises a cover body and a shell, the cover body is welded to an opening of the shell and forms a welding seam, a reinforcing boss is arranged in a heat affected zone of the welding seam on the inner wall of the shell, and the reinforcing boss is continuously arranged along the circumferential surface of the inner wall of the shell. According to the invention, the reinforcing boss is additionally arranged in the heat affected zone, which is a certain distance away from the weld joint, of the side wall of the shell, so that the position of the side wall of the shell is thickened and reinforced, the welding strength is effectively improved, and the situation that the area is fragile and cracks before the anti-explosion valve to cause heat diffusion when the battery cell is subjected to emergencies such as thermal runaway and the like is avoided. According to the battery, the welding reliability of the cover body and the shell is improved, and the safety performance of the battery under special conditions is enhanced, so that the production yield is increased, and the production cost is reduced.

The invention discloses a laser pipe cutting machine with a cooling system, which is characterized in that the outer side of a laser cutting head is sleeved with a heat dissipation suite, an inner water cavity and an outer water cavity which are communicated with each other are arranged in the heat dissipation suite, cold air pipelines are arranged in the two water cavities, and the bottom of the heat dissipation suite is connected with an air blowing box; the bottom of the air blowing box is connected with a lantern ring arranged on the lower portion of the laser cutting head in a sleeving mode, and a cold water cavity is formed in the lantern ring. A fixed seat is mounted on the outer side wall of the front chuck, and a water bag for cooling the pipe is arranged on the inner ring of the fixed seat; cold air downwards blows away hot air generated by cutting after cooling the water body, and heat interference is reduced; the outer water cavity accurately controls the water flow direction through the inflation amount of the air bag, closed circulation of extrusion-cooling-backflow-mixing is formed, and therefore the cutting head is always kept in the low-temperature working state, the service life of equipment is prolonged, and the cutting stability is improved. The problems of notch hardening and oxidation of stainless steel, aluminum alloy and other metal pipes are effectively reduced, a heat affected zone is reduced, and the notch quality is improved.

The application discloses a kind of thick gauge 430 ferritic stainless steel laser weld low-temperature rollability processing method, comprising: using-1~‑2mm negative defocusing+8~10kW low-power laser welding, the grain of heat-affected zone is refined;NiCr-3 welding wire is preheated to 300~400℃ and carried out hot wire laser welding, reduces cooling rate;Weld is implemented 700 DEG C / 10-12 seconds short time induction annealing, decomposes martensite and releases residual stress;Weld is inducted to ≥50 DEG C before rolling and restores plasticity;Optimize five rack continuous rolling parameter, and the reduction of first rack is reduced to 15%-20%.The application is by welding-heat treatment-rolling whole process synergic control, makes weld low-temperature cracking rate from 2.6 times / month reduce to 1 times below, and-10 DEG C impact toughness is promoted to 22J, cup convexity qualification rate reaches 95%, and annual economic benefit is greatly improved, applicable to the thickness 3.0~8.0mm 430 stainless steel cold rolling production, solves the technical problem that thick gauge 430 stainless steel weld is easy to crack under low-temperature environment.

The invention relates to the technical field of automobile part machining, and discloses a sheet punching device for automobile part machining, which comprises a punching table, and further comprises a recycling hopper fixedly connected to the bottom of the punching table, and a rectangular hole is formed in the punching table and used for recycling punching leftover materials into the recycling hopper; the support is fixedly connected to the bottom of the recycling hopper and used for supporting the recycling hopper and the punching table; and the moving mechanism is arranged above the punching table and is used for moving a welding gun head mounted on the moving mechanism. The lower adjusting rod driven by the two-way threaded rod and the upper adjusting rod pre-tightened by the spring form'up-down elastic clamping ', and can automatically adapt to a thin plate; in the clamping process, the first spray hole and the second spray hole spray inert gas synchronously, local protective atmosphere is formed on the upper surface and the lower surface of the notch, oxidation ablation is reduced, the hole edge heat affected zone is reduced, and the precision requirement of the high-strength welding hole of the automobile is met.

The invention discloses a three-in-one laser flame composite cutting system with a dual height tracking function, which solves the problem of respective limitations of a traditional laser cutting system and a traditional flame cutting system through technologies of intelligent switching, fault self-inspection, path optimization, cloud linkage and the like, and improves the cutting efficiency, the cutting quality and the equipment reliability. The self-adaptive switching module can automatically select a laser cutting mode, a flame cutting mode or a laser-flame composite cutting mode according to real-time feedback, and it is ensured that the optimal cutting effect is always achieved under different thicknesses and cutting conditions; according to the dual height tracking technology, through cooperative work of a high-precision laser sensor and a flame sensor, accurate control over the height of the cutting head is guaranteed, and the cutting precision and the section quality are optimized. And the fault self-checking module monitors the state of the equipment in real time and automatically switches modes or manually operates in case of faults, so that the production continuity is ensured. The intelligent cutting path optimization module dynamically adjusts the cutting path and speed, reduces deformation of a heat affected zone, and improves the smoothness of the cutting edge.

The invention relates to the technical field of coal mine supporting, in particular to a segmented collaborative welding process of a top beam hydraulic support. The method comprises the following steps: sequentially welding a plurality of rib plates and paired main rib pre-assemblies on the bottom surface of a top plate step by step, wherein the rib plates and the paired main rib pre-assemblies form the supporting rib assembly; and a first cover plate is arranged between the paired main reinforcement pre-assemblies, and welding is conducted along gaps between the first cover plate and the main reinforcement pre-assemblies to preset sub-welding points determined based on the thickness of the column socket base. And the column nest assembly is arranged on the side, away from the supporting rib assembly, of the first cover plate, and then the vertical edge of the column nest base is connected with the main rib pre-assembly in a welded mode. And the second cover plate is arranged between the column nest base and the first cover plate, and welding connection is carried out. And the first cover plate, the second cover plate and the column nest assembly located in the area below the branch welding points are welded to gaps between the main reinforcement pre-assembly. According to the welding process, the welding stress in the supporting rib assembly can be reduced, and the problem that the welding quality is poor due to superposition of heat affected zones of welding joints is solved.

The invention discloses a flange plate welding deformation compensation device, which relates to the technical field of welding, performs targeted constraint force adjustment on a local heat affected zone in a flange plate welding process by virtue of a synergistic effect of a partitioned flexible constraint assembly and an annular supporting and positioning assembly, and is different from a uniform constraint mode of a traditional integral rigid device. In the process, independent pressure control and air pressure adjustment are carried out through all the subarea air cavities, and in cooperation with real-time feedback of a temperature sensor and a laser displacement sensor, the constraining force of different areas can be dynamically changed, so that the restraining accuracy is improved. According to the method, stepped force control from initial pre-constraint to local reinforcement constraint to cooling and pressure maintaining is achieved, the mode can be matched with the local deformation trend generated by non-uniform heating of the flange plate in a more targeted mode, overall and local deformation of the flange plate in the welding process is effectively restrained, and compared with a traditional overall constraint mode, the method is more accurate.

The invention discloses a short pulse laser assisted continuous laser welding device and method. The method comprises the steps that materials are laid; a welding area is divided, and the whole welding area is divided into small areas; performing feature extraction on the small regions; constructing a speed mapping table according to the extracted different features; and planning a laser scanning path according to the speed mapping table. The short-pulse laser-assisted continuous laser welding device and method have the beneficial effects that near-infrared wavelength laser (such as 1064nm) is selected in the whole welding process, and the characteristics of high reflectivity of titanium alloy to the wavelength, high absorptivity of thermoplastic resin, relatively low absorptivity of a resin part in a thermosetting composite material and poor absorptivity of carbon fibers to the wavelength are utilized; laser energy is mainly concentrated on the thermoplastic resin layer, and local heating is achieved. The method comprises the following steps: dividing a region into small regions, extracting features, constructing a speed mapping table, controlling laser energy input, and reducing heat affected zones of the titanium alloy and the thermosetting composite material.

The invention relates to the technical field of diamond saw blades, in particular to a laser welding diamond saw blade for ultra-narrow slit cutting and a preparation method of the laser welding diamond saw blade. The copper-cobalt-tin alloy material comprises the following raw materials: copper-cobalt-tin alloy powder, tungsten carbide powder, titanium-aluminum nitride, spherical cobalt powder, rare earth yttrium powder, ferrophosphorus powder and diamond abrasive particles. According to the preparation method, the core of the preparation method lies in the combination of powder metallurgy prefabrication of the tool bit and the precise laser welding process, especially the innovative laser welding process, and the prepared diamond saw blade is high in welding seam strength, narrow in heat affected zone and extremely small in matrix deformation; the problems of base body deformation, insufficient welding seam strength, short service life and the like of a traditional saw blade in the ultra-narrow seam cutting process are solved, and the saw blade is perfectly suitable for ultra-narrow seam cutting scenes with extremely high requirements for precision and stability.

The invention belongs to the technical field of surface strengthening, and particularly relates to an aluminum alloy friction stir welding seam fatigue-free method based on rolling strengthening. The method comprises the following steps: (1) carrying out a microhardness test and a tensile test on an aluminum alloy matrix to obtain the hardness and tensile strength of the matrix; and (2) friction stir welding is conducted. The tensile strength after friction stir welding is not lower than 65% of the fatigue strength of a base body by adjusting friction stir welding process parameters; and (3) the surface of the friction stir welding part is treated. The surface of the welding seam is polished through an angle grinder and abrasive paper, so that the surface roughness of the welding seam reaches about Ra1.2 microns; and (4) rolling surface strengthening is carried out. Surface strengthening process parameters are adjusted, so that the surface hardness of a heat affected zone of the weld joint subjected to surface strengthening is not lower than the surface hardness of a matrix, the surface roughness Ra is not higher than 0.5 mu m, and the surface residual compressive stress is not lower than 100 MPa; and (5) carrying out a fatigue test.

The invention provides a battery, a battery pack and electric equipment. The battery comprises a shell and a cover plate. The cover plate is welded with the opening part of the shell. The housing includes a short side wall provided with a short wall edge and a long side wall provided with a long wall edge. The short wall edge and the long wall edge constitute at least part of the opening. A first convex part is convexly arranged on the inner side surface of the short side wall towards the battery core. The cover plate comprises a short edge and a long edge. The long edge is welded with the long wall edge, and the short edge is welded with the short wall edge. The size of the first convex part in the second direction is a1, the size of the short side wall in the second direction is a2, the short side length is b1, the long side length is b2, and the hardness of the heat affected zone is c. By selecting the value of the formula within the range of 10 * 10 <-4 > HV-1 to 4500 * 10 <-4 > HV-1, the battery not only has lower cracking risk at the short wall edge and the short edge welding part, but also has lower risk of opening the explosion-proof valve under the unexpected condition.

The invention provides a zirconium alloy metallographic specimen preparation method which comprises the following steps: (1) pretreatment: intercepting a specimen, avoiding a heat affected zone, and removing greasy dirt on the surface of the specimen; (2) mechanical grinding, wherein the mechanical grinding comprises step-by-step grinding by using metallographic abrasive paper; (3) chemical polishing: chemical polishing comprises the steps of preparing a chemical polishing solution, soaking the sample in the solution and cleaning and wiping the sample, and the chemical polishing solution comprises nitric acid, hydrofluoric acid, oxalic acid and deionized water which are mixed and placed in a polyethylene container; and (4) post-treatment: placing the sample in a nitrogen protective atmosphere furnace, forming an oxide layer on the surface of the sample, and removing residual oxide particles. According to the method, nitric acid, hydrofluoric acid, oxalic acid and deionized water are mixed and placed in a polyethylene container, and the sample is chemically polished, so that the metallographic test piece of the zirconium alloy can be safely and effectively treated, and observation and analysis of a metallographic structure are guaranteed.

The invention discloses a thermal-mechanical-metallurgical coupling numerical simulation method for low alloy steel welding and additive manufacturing, which comprises the following steps of: S1, constructing a three-dimensional model of a test piece according to the geometric size and the size of a heat affected zone of the test piece after welding or additive manufacturing, performing grid division to form grid units, and endowing the grid units with material attributes; s2, endowing the grid units with thermophysical attributes, introducing an external heat source model, solving the change of a temperature field along with time by using a finite element method until all the grid units are cooled to a set environment temperature, and exporting a temperature field model; s3, simulating a phase change process under any thermal process; and S4, calculating a stress-strain field and a displacement field by taking the temperature field model in the step S2 and the phase fraction model in the step S3 as driving external force. The temperature, phase fraction, stress-strain and displacement changes in the low alloy steel welding and additive manufacturing process can be predicted and analyzed faster and more comprehensively, the design period is shortened, and the economical efficiency of the implementation process is promoted.

The invention discloses an air cylinder welding device for magnetic resonance equipment, and relates to the technical field of welding equipment.The air cylinder welding device for the magnetic resonance equipment comprises a feeding mechanism and a polishing mechanism, and a welding assembly and a dust removal assembly are arranged on the surface of the polishing mechanism; the feeding mechanism comprises a limiting supporting seat, a limiting round hole is formed in the surface of the limiting supporting seat, a movable supporting ring is rotationally connected to the inner wall of the limiting round hole, and a clamping assembly is arranged on the inner wall of the movable supporting ring. The welding quality can be improved, the segmented skip welding strategy is adopted, the length of a single-section welding seam is smaller than or equal to 5 mm, a heat affected zone in the welding process is effectively controlled, welding deformation is reduced, the welding quality and the overall strength of an air cylinder are improved, the automation degree is high, and the feeding mechanism, the polishing mechanism and the welding assembly are integrated; the automatic production process of the air cylinder from feeding, welding to polishing is achieved, manual intervention is reduced, and the production efficiency is improved.

The invention relates to the technical field of laser cutting equipment, in particular to a laser cutting machine for cutting a machine tool body and a cutting technology.The laser cutting machine comprises a cutting table, a fixing frame arranged at the top end of the cutting table and a laser cutting head arranged at the bottom end of the fixing frame; according to the laser cutting device, when the to-be-cut area of the cover plate is cut, stable and continuous extrusion constraint can be formed, thermal expansion force generated when the long and thin groove is cut is effectively counteracted, groove wall bending and groove width deviation are reduced, and the size precision needed by precise threading and guiding of the long and thin groove is guaranteed; the heat conduction block on the abutting plate can rapidly guide out cutting heat, and in cooperation with directional blowing of the blowing assembly, heat dissipation can be accelerated so as to reduce a heat affected zone, improve the smoothness of a notch, ensure stable and reliable cutting quality, reduce subsequent assembly problems caused by thermal deformation and ensure stable and reliable cutting quality of metal manufacturing equipment during batch machining. And the overall processing efficiency of the metal manufacturing equipment is further optimized.

The invention provides a method for machining a cutting edge through composite laser based on dynamic parameter adjustment and real-time detection, and relates to the technical field of cutter machining. COMSOL is used for conducting simulation of the composite laser reinforced cutting edge, a COMSOL simulation database is established to match preset parameters, and the preset parameters are matched with the COMSOL simulation database; the heat affected zone of the cutter material strengthened by the composite laser and the corrosion amount are directly displayed in a simulation result, so that the efficiency of strengthening the cutting edge of the cutter by the laser is greatly improved; an XZ two-dimensional high-precision micro-motion platform is used, the stability and the machining precision of a laser are guaranteed, meanwhile, a two-dimensional confocal microscope is used for observing and collecting data, the data are fed back to a COMSOL database in real time by adjusting an evaluation model P, machining parameters are continuously corrected, and the machining precision is improved. And meanwhile, the preparation precision of the cutting edge of the cutter can be accurately controlled by dynamically adjusting the threshold value Q, a laser machining parameter feedback mechanism and optimizing current laser machining parameter setting, so that an ideal cutting edge of the cutter is obtained.