158results about How to "High fatigue limit" patented technology

A metal gasket capable of preventing the occurrence of cracks in a stopper while employing a wave-shaped stopper, improving the contact pressure balance around the bead to enhance the engine performance, and improving the durability of the stopper. The metal gasket is constituted by a gasket component sheet having an opening formed to face a combustion chamber, and the gasket component sheet is provided with a combustion chamber bead surrounding the opening. An inner circumference side stopper lower than the height of the combustion chamber bead is formed along the combustion chamber bead in a portion between the combustion chamber bead and the opening such that at least a section of each wave where stress amplitude is large becomes thin, a thin portion and a thick portion are arranged alternately in each wave, and the hardness of the thin portion is higher than that of the thick portion.

The invention belongs to the field of squeezing and relates to an assembly method capable of achieving hole and bush extrusion strengthening twice. The assembly method comprises the steps that firstly, strengthening is conducted on a hole (4) for the first time by means of an extrusion bar (3) with certain extrusion capacity through an extrusion drawing gun (1); secondly, a bush (5) manufactured according to requirements is placed in the hole (4); and thirdly, strengthening is conducted on the hole (4) again by means of the extrusion bar (3) with certain extrusion capacity through the extrusion drawing gun (1), and assembly of the bush (5) is completed at the same time.

The invention provides a carburizing and quenching process of an automobile gear. By adopting a pit-type gas carburizing furnace to perform carburizing treatment on the automobile gear, the carburizing and quenching process comprises the following steps: a) performing primary preheating, namely, gradually raising the temperature in the furnace to 880 +/-5 DEG C and then putting the automobile gear in the furnace, gradually reducing the temperature in the furnace to 750 +/-5 DEG C, preserving the heat for 30 minutes. The carburizing and quenching process of the automobile gear disclosed by the invention adopts a manner of repeatedly preheating and diffusing, so that the depth of an effective carburizing layer of the automobile gear is 1.1-1.2mm after carburizing to obtain a finished product, and the surface hardness is 58-62HRC, and therefore, the wear resistance, the strength and the fatigue limit of the components are improved, and the mechanical performances of the gear material are sufficiently brought into play. Moreover, distortions such as diameters changes, uneven changes in an addendum circle and an inner hole, plane warpage as well as dimension changes between gears are not produced, so that the reliability and the service life of the automobile gear are guaranteed.

The invention relates to vanadium-containing steel for a motor train unit axle and a production method and a heat treatment process thereof. The vanadium-containing steel is prepared from, by weight, C 0.24-0.30%, Si 0.20-0.40%, Mn 0.70-1.00%, Cr 0.90-1.20%, Ni 0.70-1.30%, Mo 0.20-0.30%, Cu 0.10-0.60%, Zr 0.01-0.04%, V 0.05-0.10%, Ca 0.001-0.005%, P 0.010% or below, S 0.008 % or below, [N] 0.0040-0.0070%, T[O] 0.0015 % or below, Als 0.015-0.045% and the balance Fe and other inevitable impurities. A steel structure includes tempered sorbite + a small amount of lower bainite, wherein the tempered sorbite content, close to the surface, of the axle is 100%, and the tempered sorbite content at 1/2 radius position of the axle is 80-90%. The plasticity and toughness of the steel are obviously better than those of commercial steel, the fatigue limit of the steel is remarkably higher that that of the commercial steel, and the steel has good strength toughness matching and excellent anti-fatigue performance.

The invention discloses a ceramic material and a preparation method thereof, which belong to the technical field of ceramic materials. The ceramic material is made of, by weight, 89.2-93.6% of alumina powder, 6-10% of zirconia powder and 0.4-0.8% of yttria powder. By adding the yttria into the ceramic material, dynamic performance of the ceramic material is improved, voidage of the ceramic material is decreased, and high fatigue limit can be achieved in stress alternative circulation. Further, owning to adding of the zirconia, the alumina ceramic material is reinforced, the fracture way of the ceramic material turns to be transcrystalline rupture with no crystalline grain pulled out, and accordingly abrasive wear is reduced, the ceramic material which is high in wear resistance, high in toughness and low in friction is obtained, and application range of the ceramic material in engineering is widened.

The invention relates to a magnesia-alumina-silica -lithium rare earth alloy, and the component consists of the following elements (mass %): 10-11.5 % aluminum, 0.1-1.0 % manganese, 0.1-0.8 % Lanthanun, 1-2 % lithium, 0.1-0.8 % cerium, 0.05-0.3 % praseodymium, 0.1-0.5 % Zn, 0.2-1.5 % strontium, 0.08-0.1 % silicon, and the residues are magnesium and uncontrollable impurity. The raw materials are: manganese adopts aluminium-manganese middle alloy, Lanthanun, praseodymium and cerium adopt magnesium-Lanthanun enriched,magnesium - praseodymium enriched, magnesium-cerium enriched and magnesium-Lanthanunpraseodymiumcerium enriched hardener with 15-25% rare-earth content and in magnesium-Lanthanun-praseodymium-cerium enriched hardener the proportion of Lanthanun, praseodymium and cerium is 5.5-6.5:2.5-3.5:1. The specific industrial process of this method includes: first melting magnesium, aluminum, lithium and silicon in smelter with protective atmosphere of 1.3-1.7:1 carbon dioxide and nitrogen, then adding magnesium-Lanthanun, magnesium- praseodymium, magnesium-cerium and magnesium - Lanthanunpraseodymiumcerium hardener, aluminum-manganese hardener and Znic, finally adding metallic strontium, when the temperature reduces to 710 DEG C+-10 DEG C, skimming, ingoting or diecasting. The alloy of this invention has good corrosion resisting property.

The invention discloses an alloy material characterizing in that it is composed of titanium(Ti), niobium(Nb), zirconium(Zr) and palladium(Pd). The weight percentages of the components are as follows: Nb 22-32%, Zr 4-12%, Pd 0.1-0.2%, Ti(the rest). The advantages of the product provided by the invention over the prior part are as follows: 1. favorable biocompatibility 2.low elastic modulus(30%-35%), better biomechanics compatibility 3. favorable comprehensive mechanical properties, wherein, the impact toughness(a#-[k]) is as high as 40%, the endurance limit(ªÊ#-[-1]) is as high as 12%, the fracture toughness(K#-[1]c) is high as 10% 4. better processing properties, the heat processing temperature is as low as 150íµí½200íµ, the expansion rate (ª€)is as high as 30%, the shrinkage rate after cut(ªŽ) is as high as 40%. 5.excellent corrosion proof property: the corrosion velocity is less than 0.0001mm/a in normal saline

The invention relates to a compound reinforcement method for a gear surface. The compound reinforcement method comprises the following steps: firstly, the gear surface is subjected to shot blasting with steel shots with particle size being 0.6-1 mm; then molybdenum disulfide is mixed with particles with particle size being 0.05-0.1 mm, the mixture is used for performing shot blasting continuously on a gear, and the gear with compound reinforced surface is obtained. By means of the coupled effect of two processes including powerful shot blasting and molybdenum disulfide and particle mixed shot blasting, amplitude of tooth surface compressive stress deeper than the stress in single surface treatment process is obtained, and tooth surface hardness is improved substantially. Meanwhile, the lubricity of the gear surface is improved, the friction coefficient of the tooth surface is reduced, the lubricating capacity and the surface smoothness are improved, and gear meshing vibration noise is reduced. The effect of prolonging both the flexible life and contact fatigue life of the gear simultaneously is realized. The method adopts simple process and flexible conditions, can realize batch production and has good application prospect.

The invention relates to niobium-containing steel for a motor train unit axle and a production method and heat processing technology thereof. The niobium-containing steel is prepared from, by weight, 0.24-0.30% of C, 0.20-0.40% of Si, 0.70-1.00% of Mn, 0.90-1.20% of Cr, 0.70-1.30% of Ni, 0.20-0.30% of Mo, 0.10-0.60% of Cu, 0.01-0.04% of Zr, 0.015-0.050% of Nb, 0.001-0.005% of Ca, 0.0040-0.0060% of [N] and 0.015-0.045% of Als, and the balance Fe and unavoidable impurities, the weight percentage of P, the weight percentage of S and the weight percentage of T[O] are smaller than or equal to 0.010, 0.008 and 0.0015 respectively. The steel tissue includes tempered sorbite and a small amount of lower bainite, wherein the content of the tempered sorbite on the near surface of the axle is 100%, and the content of the tempered sorbite at the 1/2 radius position of the axle is 80-90%. Plasticity and tenacity of the niobium-containing steel are obviously higher than those of commercial steel, the fatigue limit is remarkably higher than that of commercial steel, and the niobium-containing steel is good in strength and tenacity match and excellent in fatigue resistance.

The invention relates to a treatment method for a brass texture antifatigue aluminum alloy panel, which is characterized in that multiple times of warm rolling is performed on an aluminum alloy hot rolling material until reaching the designed thickness of the aluminum alloy panel, and after annealing treatment and solution treatment, short-term artificial aging is performed. According to the invention, a treatment process of multiple times of warm rolling and annealing is adopted; by virtue of warm rolling, grains of the alloy can be effectively refined, the return process of alloy can be promoted, deformation energy storage can be reduced, and recrystallization can be inhibited; and by virtue of primary annealing treatment, annealing temperature and heat insulation time can be controlled, grains cannot grow up, and a deformation texture can be retained, thus obtaining a relatively strong deformation texture. The treatment method is simple in process method and convenient to operate, can effectively improve the composition and the volume fraction of the texture in an aluminum alloy matrix, can effectively prolong the fatigue life of the aluminum alloy on the premise of ensuring that aluminum alloy strength and ductility meet alloy performance requirements, is suitable for industrial application, and provides a feasible technical solution for preparation of aluminum alloy material for aviation and spaceflight.

The invention discloses a coating material and process method for repairing a main bearing of a shield tunneling machine, and belongs to the technical field of surface treatment. The coating materialfor repairing the main bearing of the shield tunneling machine is prepared from the following components in percentage by mass: 0.53-0.60% of C, 0.8-1.1% of Si, 0.5-0.8% of Mn, 0.9-1.2% of Cr, 0.15-0.30% of Mo, 0.10-0.20% of W, 0.05-0.1% of Cu and the balance of Fe and inevitable impurities, wherein the mass percentage of the components adds up to 100%. The powder is used for repairing the main bearing of the shield tunneling machine through a laser cladding process, so that an abrasion-resistant, corrosion-resistant and fatigue-resistant coating is laser-clad on the raceway surface of the main bearing, the service life of the main bearing is prolonged, the service life of the shield tunneling machine is prolonged, and a good effect is played on reducing the production cost.

The invention relates to a three-element mixed protective gas for aluminum alloy MIG welding and a welding method. The three-element mixed protective gas comprises helium, argon and a small amount of nitrogen, wherein based on the volume percentage, the helium accounts for 20-40%, the argon accounts for 59.974-79.995%, and the argon accounts for 0.005-0.026%. The welding method comprises the following steps: adopting a meltable welding wire as an electrode, taking an electric arc between the continuously feed-in welding wire and a welded workpiece as a heat source to melt the welding wire and a base metal, as the welding wire is continuously molten, using a molten drop manner to transit the welding wire to a welding pool, fusing the welding wire with the molten base metal, forming weld metal after condensing, and continuously delivering the three-element mixed protective gas through a welding gun nozzle to the welding area, so as to prevent the electric arc, the molten pool and the adjacent base metal from harmful action of the ambient air. The three-element mixed protective gas and the welding method can improve anti-fracture performance and fatigue performance of the welding structure, obtain larger welding penetration under the same welding heat input, and reduce the welding heat input.

The invention relates to a heat treatment technology for niobium and titanium-containing steel for a motor train unit axle. The technology comprises the following steps of 1, normalizing, wherein the niobium and titanium-containing steel for the high-speed motor train unit axle is heated to the temperature of 870 DEG C to 900 DEG C, the heating and heat preservation time in the temperature section is calculated according to 1.2 min/mm-1.7 min/mm, and air cooling is conducted; 2, quenching, wherein vanadium-containing steel for the high-speed motor train unit axle is heated to the temperature of 860 DEG C to 890 DEG C, the heating and heat preservation time in the temperature section is calculated according to 1.5 min/mm-2.0 min/mm, and then water quenching and oil cooling are conducted; 3, tempering, wherein the niobium and titanium-containing steel for the high-speed motor train unit axle is heated to the temperature of 620 DEG C to 680 DEG C, the heating and heat preservation time in the temperature section is calculated according to 2 min/mm-2.5 min/mm, and then the treated steel is air-cooled to room temperature. Compared with the prior art, the treated steel has the advantages of being high in strength and excellent in anti-fatigue performance.

The invention discloses a mending method for mechanism processing compression spring that includes the following steps: taking spring backfire and controlling the rigidity at HRC44-HRC48; strutting every pitch of the spring; taking heating process of to the spring and ensuring the rigidity between HRC50-HRC53 after heating process; snapping 24hours and finishing mending. The invention could improve mechanism processing compression spring yield and sharply decrease produce cost.

The invention discloses a gradient copper-based alloy cable conductor, which consists of a core layer and a skin layer, wherein the core layer and the skin layer form a double-metal concentric circle structure; the core layer is a copper-based alloy; the skin layer is pure copper; and the conductor is cast by a double-layer composite material one-step coating device. With the double-metal concentric circle structure, the gradient copper-based alloy cable conductor has high interface metal atom lattice distribution transitivity, high crystal bonding strength, ordered crystalline phase structure, high purity, high electrical performance, tight core layer and skin layer bonding strength and high mechanical performance compared with the conventional non-gradient copper-based alloy cable conductor such as copper clad steel, copper clad aluminum and aluminum clad steel.

The invention discloses a 3D printing and forming integrated program-controlled valve group. The advantage of quick and precise forming of a 3D printing technique is used, so that the integrated program-controlled valve group in which a flow channel is integrated is obtained; multiple complex pipelines and valve components are integrated with the integrated program-controlled valve group in the mode of unit blocks in the prior art, so that an onsite valve area of an adsorption processing system has the advantages of the compact structure, small size and convenience in modularization, skid mounting, equipping and vehicle mounting. Additionally, for the integrated program-controlled valve group, a novel 3D printing and forming process in which a printing and forming process, a permeating process and a sintering process are combined is provided, the quick forming characteristic of 3D printing is taken, after a workpiece is formed, the surface of the inner wall of a complex flow channel issmooth and has excellent antiwear cavitation resistant capability, and the problems of difficulty in processing and forming and poor surface performance of the wall of the flow channel after formingwhen the integrated level of the designed flow channel is overhigh in the skid mounting design process of the valve area of the adsorption processing system are completely solved.

The invention discloses a modular space truss structure light semi-submersible suspension cable deep sea net cage. The net cage is characterized in that a net cage framework is modularly constructed and expanded by truss nodes and truss rod pieces, and comprises a top surface truss, a semi-submersible truss arranged on the top surface truss, and a bottom surface truss; the top surface truss and the bottom surface truss are multilayer trusses in the inner and outer directions and comprise buoyancy adjustable layers and buoyancy non-adjustable layers; the semi-submersible truss comprises a buoyancy adjustable layer; and a plurality of groups of suspension cables are included and are arranged between the top surface truss and the bottom surface truss. The net cage framework is constructed ina modular design mode, the multi-layer truss structure meets the requirement for good strength and safety, the unit use cost of equipment is greatly reduced, and a road is laid for large-scale offshore culture; through active adjustment of buoyancy adjustable points, the top surface truss and the bottom surface truss have the active approaching and folding functions, rapid contraction of the netting and the culture space is achieved, rapid fish collection or transfer is achieved in cooperation with pumping, and external disasters such as storms are avoided.

The invention relates to a demonstrating device, and particularly to a pressure demonstrating device for physics education. The invention aims to settle a technical problem of providing the pressure demonstrating device for physics education, wherein the pressure demonstrating device has advantages of obvious demonstrating result, low demonstrating difficulty and simple operation. For settling the technical problem, the pressure demonstrating device for physics education comprises an elastic component, a first slide rail, a second slide rail, a second slide block, a first pressure plate, a first piston, etc. A first bracket, a housing, a second slide rail and an elastic component are successively arranged on ground from left to right. The left side of the housing contacts with the first bracket. The right end of the first bracket is provided with a second bracket. The upper end of the second bracket is provided with a cylinder. The pressure demonstrating device realizes effects of obvious demonstrating result, low demonstrating difficulty and simple operation.

The invention discloses a thin-sized hot-continuous-rolled steel for furniture and a method for producing the same. The steel comprises the following chemical components by weight percent: 0.05-0.07% of C, 0.20-0.30% of Si, 1.8-2.0% of Mn, 0.070-0.090% of Nb, 0.0010-0.0020% of B, 0.14-0.20% of Ti, 0.50-0.60% of Cr, 0.01-0.06% of Al, no more than 0.02% of P, no more than 0.010% of S, no more than 0.008% of N and the balance of Fe and inevitable impurities. According to the thin-sized hot-continuous-rolled steel for furniture and the method for producing the same, elements of Cr and Ti are added for compounding, and thermo mechanical control process (TMCP) technological parameters are controlled, thus, a superfine lath bainite structure with excellent comprehensive performance is obtained, the yield strength of the material is enabled not to be less than 800 mega pascals, and moreover, the steel has good ductility and toughness.