24 results about "Surface fatigue" patented technology

This invention provides a rapid assessment method for fatigue cracks and scratches on the surface of metal components. It is a detection and analysis method for distinguishing between fatigue cracks and micro-scratches on metal surfaces, and for analyzing and predicting defect development. Its key feature is that it differentiates between fatigue cracks and micro-scratches by detecting and identifying the shape of the opening extending along the depth direction of the defect. This invention utilizes a large amount of data analysis to determine the shape of the defect opening edge, achieving clear differentiation and significantly reducing safety hazards caused by missed detections.

To provide a steel part with excellent surface fatigue strength and a method for manufacturing the same. [Solution] The device comprises a steel core, a compound layer containing iron nitride, and a nitrogen diffusion layer between the steel core and the compound layer, wherein the steel core has the following composition by mass%, C: 0.05~0.30%, Si: 0.05~2.00%, Mn: 1.50~3.00%, P: 0.030% or less, S: 0.100% or less, Cr: 0.05~2.00%, V: 0.02~1.30%, Al: 0.100% or less, and N: 0.0250% or less. A steel part and a method for manufacturing the same, having a chemical composition containing the following, with the remainder being Fe and impurities, a compound layer thickness of more than 3 to 30 μm, the compound layer containing more than 50% γ' phase by area ratio, with the remainder being ε phase, containing 5 to 40% γ phase by area ratio in the region up to 10 μm from the surface of the nitrogen diffusion layer, and having a Vickers hardness of 580 HV or more at a depth of 0.05 mm from the surface of the nitrogen diffusion layer.

The invention discloses a subsurface contact fatigue damage calculation method considering surface integrity characteristic parameters, relates to the technical field of mechanical part fatigue analysis in engineering, and solves the problem that existing mainstream fatigue analysis software lacks a subsurface contact fatigue analysis module. The method comprises the steps of finite element model input and subsurface layer adaptive grid generation, surface integrity characteristic parameter gradient curve characterization, surface integrity characteristic parameter coupling effect model establishment, and subsurface fatigue damage and danger depth prediction. The core of the method is to generate a sub-surface layer adaptive grid, characterize a gradient curve of surface integrity characteristic parameters changing along the depth, and establish a coupling effect model of each characteristic parameter to sub-surface contact fatigue damage, thereby realizing damage prediction and dangerous area positioning functions.

The embodiment of the present application belongs to the field of rail transit technology, and discloses a locomotive wheel surface fatigue damage prediction method and equipment. The corresponding method comprises the following steps: determining a first relationship parameter between a surface length and an internal length and a second relationship parameter between the internal length and an internal depth according to the surface length, the internal length and the internal depth of the pre-acquired crack of the locomotive wheel; generating a wheel-rail contact damage prediction model under the amplitude load condition according to the damage index distribution inside the wheel-rail contact spot under the static wheel load, the first relationship parameter and the second relationship parameter; generating a lateral damage index distribution of the locomotive wheel according to the wheel-rail contact damage prediction model; and predicting the surface fatigue damage condition of the locomotive wheel according to the lateral damage index distribution. The method provided by the present application can more accurately calculate the surface fatigue damage condition of the wheel under different operation lines, and obtain more reliable data.

The present application is a kind of traditional and fast grinding combined rail corrugation grinding method, which is suitable for the field of rail corrugation engineering technology.The method comprises the following steps: special detection is carried out on the rail before grinding, a corresponding rail corrugation treatment scheme is formulated according to the special detection result, the rail profile is ground by a traditional grinding car first, the wave length below 300mm is mainly treated, the surface fatigue disease is removed, and the rail head hardening layer is eliminated;then, the fast grinding car is operated, the wave length not less than 300mm is mainly treated, and the overall smoothness of the rail line is improved;the grinding operation scheme is designed, the corrugation mode process is optimized;the grinding operation is carried out according to the designed operation scheme, and the quality acceptance after grinding is carried out.The present application realizes efficient, high-quality and high-economy treatment of rail corrugation, is suitable for both ordinary speed railway and high-speed railway, can improve the wheel-rail contact relationship, prolong the service life of the rail, and improve the safety and stability of vehicle operation.

To provide a steel part with excellent surface fatigue strength and a method for manufacturing the same. [Solution] The invention comprises a steel core and a hardened layer on the steel core, wherein the steel core has the following composition in mass%, C: 0.30~0.60%, Si: 0.05~2.00%, Mn: 1.50~3.00%, P: 0.030% or less, S: 0.100% or less, Cr: 0.05~2.00%, Mo: 0.12~1.30%, V: 0.02~1.30%, Al: 0.005~1.000%, and N: 0.0 A steel part and a method for manufacturing the same, having a chemical composition containing 250% or less of [unspecified element] with the remainder being Fe and impurities, a microstructure at a depth of 0.10 mm from the surface containing 40% or less by volume of retained austenite, an average N concentration in the region from the surface to a depth of 0.10 mm being 1.80 atomic percent or more, and a Vickers hardness at a depth of 0.10 mm from the surface being 650 HV or more.

This invention provides a cracked control surface fatigue and functional reliability testing system, belonging to the technical field of cracked control surface testing. The system includes a test support frame, a deformation support device, a gravity-eliminating follow-up loading device, and a test control device located outside the test support frame for test control. Multiple sets of gravity-eliminating follow-up loading devices are provided, with one or more sets on both the upper and lower control surfaces. This system employs dual follow-up loading devices to solve the problem of dual-control surface follow-up loading, meeting the requirements of tensile and compressive bidirectional loading and large-range motion following. Furthermore, the follow-up loading device is capable of eliminating the non-axial component of gravity, eliminating additional accessory loads, improving test loading accuracy, and achieving accurate simulation of aerodynamic loads on the control surface.

The invention provides a wind power bearing yaw gear ring friction surface fatigue life detection device and a detection method thereof, and relates to the field of gear ring friction surface detection. Four detection brackets are fixedly mounted at the top of the detection seat; four limiting shells are mounted on the outer side of the detection seat; when a clamping block matched with a new gear ring is selected for installation, a plug pushes a detection sliding block to overcome the resistance of a spring to stably move backwards, a limiting head is forced to completely retreat from a fixing hole, through the coherent action, it is confirmed that the installation of the clamping block reaches the preset positioning precision, and a road is more smoothly fastened and paved through a fixing screw; the problems that a common detection device is not provided with a good auxiliary mechanism, the installation position of a fixing mechanism cannot be detected in the fixing mechanism replacing process, deviation occurs when the fixing mechanism clamps a gear ring, and the friction face fatigue life detection precision is reduced are solved.

The invention discloses a power transmission line spacer fatigue performance comprehensive evaluation method under a simulated natural environment, and belongs to the technical field of power transmission line detection, and the method comprises the steps: S10, carrying out the simulation of related environments, including climate, wind power and vibration, of a spacer; the climate comprises environment temperature, air humidity and sunlight intensity; and S20, a monitoring interval is set based on the climate, the monitoring interval comprises setting of climate changes with a basic value as a setting target, and the basic value comprises the environment temperature of 0 DEG C. By simulating climate (temperature, humidity and sunlight), wind power, vibration and other conditions in the natural environment, the stress condition and fatigue performance of the spacer in actual operation can be reflected more truly, and then the feature change of the fatigue crack on the surface of the spacer can be analyzed in detail so as to accurately predict the initiation and extension path of the crack and the fatigue life.

To provide a steel component which is excellent in surface fatigue strength.SOLUTION: A steel component includes a steel core part, a compound layer, and a nitrogen diffusion layer existing between the steel core part and the compound layer, wherein the steel core part has a predetermined chemical composition, thickness t of the compound layer is 5 to 30 μm, an area ratio of a γ' phase in the compound layer at a depth of 0 to t / 2 from the surface of the compound layer is 70% or more, the remainder is an ε phase, an area ratio of the ε phase in the compound layer at a depth of t / 2 to t from the surface of the compound layer is 70% or more, the remainder is the γ' phase, Vickers hardness at a depth position of 0.05 mm from the surface of the nitrogen diffusion layer is 630 HV or more, and Vickers hardness at a depth position of 1.00 mm from the surface of the nitrogen diffusion layer is 210 HV or more.SELECTED DRAWING: None

The utility model discloses a buffer structure of a discarded bottle rack, which relates to the field of glass bottle production and has the technical key points that the buffer structure comprises a base and a discarded bottle rack body arranged at the top of the base, a discarded bottle cavity is formed in the discarded bottle rack body, a discarded bottle opening communicated with the discarded bottle cavity is formed in one side of the discarded bottle rack body, and the discarded bottle opening is communicated with the discarded bottle cavity. A connecting groove communicated with the bottle abandoning cavity is formed in the other side of the bottle abandoning frame body and communicated with an external bottle abandoning channel, and the purpose is to solve the problem that when a glass bottle enters from the bottle abandoning opening, the falling process of the glass bottle is lack of effective buffering, so that the glass bottle directly impacts the inner bottom face of the bottle abandoning frame with large impact force, and the bottle abandoning efficiency is improved. The technical problems that due to the fact that the bottom face in the bottle abandoning frame bears instantaneous impact loads for a long time, local stress is concentrated, fatigue cracks on the surface of a material are accelerated, bottom face breakdown in the bottle abandoning frame is caused, finally defective glass bottles overflow from a breakdown opening, and use is inconvenient are solved.

The utility model provides an eutectic welding structure of a multi-chip integrated LED patch, which comprises an LED welding circuit board, the LED welding circuit board comprises a substrate body, a plurality of supporting strips are arranged at the bottom of the substrate body, a bottom plate is arranged among the four supporting strips, and a welding groove is arranged in the bottom plate. The welding points are separated from the substrate body through the supporting strips and the bottom plate which are arranged under the substrate body, so that the LED patch body is separated from the welding points of the substrate, and the situation that heat is directly transmitted to the substrate body, the substrate body is heated unevenly, so that a welding layer is cracked or an interface is layered, the structural reliability is reduced, and the service life of the substrate is prolonged is avoided. Especially under a temperature cycle working condition, fatigue accumulation of a welding surface accelerates damage of a substrate body.

To provide a carburized component for a machine structure which has excellent surface fatigue strength and in which heat treatment strain is suppressed.SOLUTION: A carburized mechanical structural component according to the present invention satisfies the chemical composition described in the specification, and 1A defined by Formula (Fn1A) is 0.27 to 0.35, and Fn1A and Fn2A defined by Formula (2A) satisfy Formula (3A). Fn1A = exp (-0.01 * (170 - 45 * Mn - 15 * (Cr + Mo))) (1A) Fn2A = 20.0 * C + 10.0 * Si + 30.0 * Mn - 10.0 * Cr -0.5 * Mo + 2000.0 * N (2A) Fn1A * Fn2A ≥ 20.1 (3A) SELECTED DRAWING: None

The invention provides a cracking type control surface fatigue and functional reliability test system, and belongs to the technical field of cracking type control surface tests. The system comprises a test support integral frame, a deformation support device, a plurality of sets of follow-up loading devices for eliminating gravity influence and a test control device which is arranged outside the test support integral frame and is used for performing test control, and the upper control surface and the lower control surface are respectively provided with one or more follow-up loading devices for eliminating gravity influence. According to the system, the problem of double-control-surface follow-up loading is solved by adopting a double follow-up loading device, and the requirements of tension-compression two-way loading and wide-range movement follow-up are met; and the follow-up loading device is a follow-up loading device capable of eliminating a gravity non-axis component, so that an additional accessory load is eliminated, the test loading accuracy is improved, and accurate simulation of the aerodynamic load of the control surface is realized.

The application discloses a method for comprehensively evaluating fatigue performance of a spacer of a power transmission line in a simulated natural environment, and belongs to the technical field of power transmission line detection. The method comprises the following steps: S10, simulating relevant environments of the spacer, wherein the relevant environments include climate, wind power and vibration; the climate includes environmental temperature, air humidity and sunshine intensity; and S20, setting a monitoring interval based on the climate, wherein the monitoring interval comprises setting changes of the climate with a basic value as a setting target, and the basic value includes an environmental temperature of 0 DEG C. The application can more truly reflect stress conditions and fatigue performance of the spacer in actual operation by simulating conditions such as climate (temperature, humidity and sunshine), wind power and vibration in the natural environment, and can accurately predict crack initiation, an expansion path and fatigue life by analyzing characteristic changes of surface fatigue cracks of the spacer in detail.

To provide a steel material in which excellent surface fatigue strength can be obtained in a component for a vacuum carburized machine structure used as a stock and produced, and also, heat treatment strain upon vacuum carburizing and quenching treatment is reduced.SOLUTION: The steel product according to the present invention satisfies the chemical composition described in the description, Fn1A defined by Formula (1A) is 0.27 to 0.35, and Fn1A and Fn2A defined by Formula (2A) satisfy Formula (3A). Fn1A = exp (-0.01 * (170 - 45 * Mn - 15 * (Cr + Mo))) (1A) Fn2A = 20.0 * C + 10.0 * Si + 30.0 * Mn - 10.0 * Cr -0.5 * Mo + 2000.0 * N (2A) Fn1A * Fn2A ≥ 20.1 (3A) SELECTED DRAWING: None

The present application relates to a kind of high-hardness material large-size turbine disc mortise processing process method, step one: cutting test before processing;Step two: formal part processing step three: through magnetic abrasive process, remove the 0.003mm thickness remelt layer after electric spark cutting 1 repair 3;Step four: through shot peening strengthening effect, improve surface fatigue performance, the technical scheme of the present application is verified by designing fatigue performance test, performance reaches practical demand, solidifies each process flow and parameter, and is regularly checked, guarantee processing quality stability.The present application adopts precision wire electrical discharge machining technology, combines low-cost surface defect post-processing and strengthening technology to ensure product performance.

The invention discloses a three-dimensional eddy current thermal imaging detection device and method for fatigue cracks on the surface of a steel rail, and belongs to the field of material science, and the device comprises hardware equipment which comprises a detection motion platform, a mechanical arm device, a central control box, a three-dimensional eddy current thermal imaging module and an induction heating module; the mechanical arm device and the central control box are mounted at the top end of the detection motion platform, and the three-dimensional eddy current thermal imaging module and the induction heating module are both mounted at the output end of the mechanical arm device; the induction heating module is used for carrying out induction heating on the surface of a steel rail test block; the three-dimensional eddy current thermal imaging module is used for simultaneously acquiring infrared thermal image information and structured light three-dimensional information of the surface of the steel rail; and the software analysis system runs in the data acquisition and analysis module and is used for processing infrared thermal image information and structured light three-dimensional information through a three-dimensional eddy current thermal imaging crack detection algorithm and outputting a detection result. Infrared and structured light imaging results are fused, the detection precision is high, and the method is suitable for steel rail early-stage fatigue defect detection.

The wear-resistant stainless steel screw rod comprises a stainless steel screw rod body, a connecting rod is integrally formed at the middle end of the right side of the stainless steel screw rod body, a screw rod main body is integrally formed on the right side of the connecting rod, external threads are arranged on the surface of the screw rod main body, and a first wear-resistant layer is arranged on the outer surface of the external threads. A second wear-resistant layer is arranged on the outer surface of the first wear-resistant layer, and a third wear-resistant layer is arranged on the outer surface of the second wear-resistant layer. Three wear-resisting layers, namely the first wear-resisting layer, the second wear-resisting layer and the third wear-resisting layer, are arranged on the surface of the screw rod main body through the external threads. The three abrasion-resistant layers form a composite abrasion-resistant protection system through different material characteristics and structural design, friction, abrasion and surface fatigue can be effectively resisted, the abrasion resistance of the lead screw in long-term use is remarkably improved, and the service life is prolonged.

The invention provides a welding structure surface fatigue crack propagation life evaluation method and system, and relates to the technical field of crack life evaluation and prediction.The method comprises the steps that generalized structural stress in a tensile load mode and generalized structural stress in a bending load mode are calculated through numerical simulation; a welding seam gauge is used for actually measuring the geometrical characteristics of the welding joint, and geometrical characteristic parameters of the welding joint are extracted; generating a tensile load geometric correction factor and a bending load geometric correction factor associated with the crack characteristic parameters through multivariate nonlinear regression analysis; constructing a stress intensity amplification factor correction model in a shallow surface crack stage, and further generating a full-thickness stress intensity amplification factor in the shallow crack stage; and iteratively calculating the evolution of the crack depth, and outputting a fatigue life prediction result of the welding joint. According to the method, the stress intensity factor of the crack on the surface of the welded joint is accurately solved, and the efficiency of crack propagation life evaluation is improved.

To provide a steel bar that exhibits superior surface fatigue strength.SOLUTION: A steel bar having a chemical composition comprising, in mass%: C: 0.30-0.50%, Si: 0.05-0.25%, Mn: 1.50-2.60%, P: 0.030% or less, S: 0.100% or less, Cr: 0.50-0.95%, Mo: 0.02-0.35%, V: 0.02-0.35%, Al: 0.005-1.000%, and N: 0.0250% or less, wherein the contents of Si, Mn, Cr, V, and Al satisfy the following formula (1) (where each element symbol in the formula indicates the content of the corresponding element in mass%), the remainder being Fe and impurities; the metallographic structure contains 30% or more in area fraction of bainite and martensite in total; and the Vickers hardness is from 180 to 300 HV. Formula (1): 24≤(Mn+3Cr+2 V+6Al) / Si.SELECTED DRAWING: None

The invention relates to the technical field of fatigue monitoring, in particular to an unmanned aerial vehicle vision-based aircraft surface fatigue crack inspection device, which comprises an unmanned aerial vehicle, an image acquisition module, a clamping structure, an air bag, a flow guide box, an air pump and an air flow triggering assembly, and is characterized in that the image acquisition module is arranged on the unmanned aerial vehicle, and the clamping structure is arranged at the bottom of the unmanned aerial vehicle; the air bag is arranged on the side, attached to the fuselage, of the clamping structure. The flow guide box is arranged at the top of a fuselage of the unmanned aerial vehicle, and an airflow inlet and an airflow outlet are formed in the flow guide box; the air pump is arranged in the flow guide box, the output end of the air pump communicates with the air bag, and the airflow triggering assembly is used for triggering a power source of the unmanned aerial vehicle to be communicated with the air pump in the flow guide box under the airflow effect to inflate the air bag when the aircraft taxies and takes off. According to the method, the fatigue cracks of the fuselage of the aircraft are visually monitored in the taxiing stage before the aircraft takes off, the monitored unmanned aerial vehicle is ejected when the aircraft takes off, and flight of the aircraft is not affected.

The invention discloses rare earth element doped and multi-component microalloyed cylinder sleeve cast iron based on Tarkall-C alloy and a preparation method of the rare earth element doped and multi-component microalloyed cylinder sleeve cast iron, and belongs to the field of ship low-speed engines. The invention aims to solve the problems that the gray cast iron is easy to abrade and damage due to surface fatigue under the working conditions of high cylinder temperature, high load and low speed. The rare earth element doped and multi-component microalloyed cylinder liner cast iron based on the Tarkall-C alloy is composed of rare earth elements, Ni, Cr, Mo, V, Nb, C, Si, Mn, P, S, Cu and the balance Fe. The method comprises the steps of 1, modeling; 2, weighing; 3, smelting; 4, inoculation; and 5, pouring. The rare earth element doped and multi-component microalloyed cylinder sleeve cast iron based on the Tarkall-C alloy and the preparation method of the cylinder sleeve cast iron are provided.

The application provides a rail surface fatigue damage degree evaluation method based on a rating atlas, relates to the field of railway maintenance technology, and comprises the following steps: preparing a rail surface fatigue damage rating atlas; obtaining a photo of the rail surface of a rail to be evaluated; comparing the photo with the rail surface fatigue damage rating atlas; and determining the rail surface fatigue damage degree grade of the rail to be evaluated according to the rail surface fatigue damage rating atlas. The rail surface fatigue damage degree evaluation method based on the rating atlas can quickly determine the rail surface fatigue damage degree at a maintenance site, and provides a scientific decision basis for subsequent polishing and maintenance processes.