67results about How to "Quenching temperature is low" patented technology

A duplex heat treating process for workpiece includes such steps as heating to austenite state, penetrating C or C and N to obtain a prepenetrated layer, lowering temp to 620-720 deg.c, penetrating N or N and C, direct quenching, and having time effect at 200-300 deg.c or isothermal quenching at 200-300 deg.c. Its advantages are high hardness (greater than 900 HV) and lower deformation.

The invention discloses an automobile gearbox gear carburizing and quenching heat treatment method. The method comprises the following steps: 1, carburizing: placing a gear in a heating furnace, and rising temperature of the heating furnace from room temperature to 900+/-5DEG C for carburizing for 3-4h, wherein the carbon potential CP in a strong carburizing stage is 1.06+/-0.3C%, and the carbon potential CP in a diffusion stage is 0.85+/-0.03C%; 2, quenching: cooling the obtained carburized gear to 830+/-5DEG C, samming for 25-35min, and quenching in 90+/-10DEG C quenching oil; and 3, tempering: tempering the obtained quenched gear at 165+/-5DEG C for 2-3h. The proper reduction of the carburizing temperature and the quenching temperature, the rising of the temperature of the quenching oil and the proper rising of the carburizing carbon potential are carried out on the premise of guaranteeing the quality of a carburized layer, so the carburizing time is not prolonged, and the energy consumption is reduced; and the appearance of black microstructures is prevented, so the surface hardness, the wear resistance and the fatigue strength of the gear are obviously improved, deformation is reduced, the driving balance of the gear is improved, noises are reduced, and the service life of the gear is prolonged.

The invention discloses a more than 630MPa level high strength steel bar comprising the following components: by weight, 0.28%-0.38% of carbon, 0-0.35% of silicon, 0-0.90% of manganese, 0.80%-1.50% of Cr, 3.00%-4.00% of nickel, 0.40%-0.60% of molybdenum, 0-0.015% of P, 0-0.015% of sulfur, 0-2.0ppm of hydrogen, 0.10%-0.20% of vanadium, 0-0.025% of titanium, 0-0.20% of copper, 0-0.05% of aluminum, 0-0.50% of residual elements and the balance of Fe; the invention also designs an application method of the more than 630MPa level high strength steel bar in reinforced concrete; and the more than 630MPa level high strength steel bar has the advantages of high strength, steel saving, no pollution, good hardenability, low tendency to crack and low relaxation degree.

The invention relates to a method for preparing manganese chilled bainitic steel, belonging to the field of alloy steel. Firstly, after smelted by the normal steelmaking process, steel is forged, rolled or cast into a product, the product is air-cooled to 480 to 700 DEG C, is processed by water-cooling or oil cooling or salt-alkali solution cooling until 200 to 250 DEG C (or the product is reheated to a temperature of 30 to 50 DEG C higher than the austenitic transformation critical point, is air-cooled to 480 to 700 DEG C and then is processed by water-cooling or oil cooling or salt-alkali solution cooling until 200 to 250 DEG C), and then is taken out to be air-cooled or slowly cooled to room temperature; and the product is heated to 200 to 600 DEG C and then is tempered after the temperature is preserved for 1 to 5 hours. Compared with other types of steel with the same strength, the manganese chilled bainitic steel of the invention has the advantages of low alloy cost, increased performance and no complex working procedure in the whole production technology, thereby obviously reducing the production cost.

The invention relates to a processing method for a gear, especially to a processing technology for a gearbox gear. The processing technology comprises the following steps: step 1, blanking and forging so as to obtain a cylindrical blank; step 2, homogenization treatment of components of the forged blank and drilling of a center hole through lathing; step 3, gear hobbing out of the cylindrical blank via a hobbing machine; step 4, carbonization of a workpiece; step 5, cooling and quenching after carbonization; and step 6, machining of the workpiece so as to form the gear. The processing technology provided by the invention has the following beneficial effects: a, carburizing temperature and quenching temperature are reduced, carburizing time is not prolonged, and energy consumption is reduced; b, generation of a black structure is prevented, a uniform carburizing layer is obtained, the microstructure of the carburizing layer having undergone carbonization and quenching is improved, an optimal metallographic structure is obtained, and thus, surface hardness, wear resistance and fatigue resistance of the gear are obviously improved; and c, deformation is reduced, gear processing and assembling dimension precision of the gear is improved, gear transmission balance is enhanced, noise is reduced, and the service life of the gear is prolonged.

The invention discloses a thermal treatment method for carburizing and quenching of gearbox gears. The thermal treatment method includes the steps of A, carburizing, B, quenching and C tempering. In the step of A, carburizing, the gears are placed in a heating furnace, the temperature of the heating furnace is increased from the room temperature to the temperature of 850-900 DEG C for carburizing, and carburizing time is 2-5 h; the carburizing process includes a beginning stage, a strong carburizing stage and a diffusion stage; the carbon potential (CP) of the beginning stage is 0.9-1 C%, the CP of the strong carburizing stage is 1-1.1 C%, and the CP of the diffusion stage is 0.8-0.9 C%; the time of the beginning stage is 12-15 min, the time of the strong carburizing stage is 200-220 min, and the time of the diffusion stage is 20-40 min. In the step of B, quenching, the carburized gears are cooled to 810-850 DEG C, then temperature equilibrium is carried out for 20-40 min, and then the gears are quenched in quenching oil with the temperature being 85-95 DEG C. In the step C, tempering, the quenched gears are subjected to tempering at the temperature of 155-170 DEG C for 1-2 h.

The invention provides a heat treatment process for surface hardening and carbonitriding of hydraulic parts, which includes the following steps: a washing the hydraulic parts preparing for heat treatment to remove greasy dirt; b warming a carburizing multi-purpose furnace, and performing pre-carburizing treatment; c putting the hydraulic parts washed cleanly through the step a in the carburizing multi-purpose furnace, and performing strong carburizing; d adjusting carbon potential after the strong carburizing to perform diffusion; e putting the hydraulic parts after carbonitriding in the stepd in a quenching chamber of the carburizing multi-purpose furnace to be quenched, filtering oil and discharging from the furnace; and f washing the hydraulic parts of the step e, and putting the hydraulic parts in a tempering furnace to be tempered to obtain products.

The invention discloses a heat processing method for carburizing and quenching. The method comprises the following steps: A) a carburizing step, placing a gear in a heating furnace, and rising temperature of the heating furnace from room temperature to 850-900 DEG C for carburizing for 2-5 h, wherein the carbon potential CP in a strong carburizing stage is 1.02-1.1C%, and the carbon potential CP in a diffusion stage is 0.8-0.9C%; B) a quenching step: cooling the obtained carburized gear to 810-850 DEG C, equalizing the temperature for 20-40min, and quenching in 85-95 DEG C quenching oil; and C) a tempering step: tempering the obtained quenched gear at 155-170 DEG C for 1-2 h. The proper reduction of the carburizing temperature and the quenching temperature, the rising of the temperature of the quenching oil and the proper rising of the carburizing carbon potential are carried out on the premise of guaranteeing the quality of a carburized layer, so the carburizing time is not prolonged, and the energy consumption is reduced; and the appearance of black microstructures is prevented, so the surface hardness, the wear resistance and the fatigue strength of the gear are obviously improved, deformation is reduced, the driving balance of the gear is improved, noises are reduced, and the service life of the gear is prolonged.

The invention discloses a manufacturing method of an FB2 valve forged piece for an ultra-supercritical turbine. The method comprises the following steps of smelting, forging, valve forged piece heat treatment, machining and heat treatment. The invention further discloses a valve forged piece manufactured by the adoption of the manufacturing method of the FB2 valve forged piece for the ultra-supercritical turbine. According to the manufacturing method, operation is reasonable, effective boron is contained, hardenability of the forged piece reaches the standard, the grain size of the final forged piece is larger than or equal to the grade 3, and according to the manufacturing method of the FB2 valve forged piece for the 625 DEG C ultra-supercritical turbine and the FB2 valve forged piece, the situation that Y-shaped cracks appear in the center of the forged piece is avoided.

The invention relates to a low alloy die steel material which comprises the following components by weight: 0.68-0.78% of C, 0.7-1.0% of Si, 0.7-1.1% of Mn, not more than 0.02% of P, not more than 0.02% of S, 2.2-2.5% of Cr, 0.2-0.3% of Mo, 0.15-0.35% of V, 0.3-0.4% of Ni, the balance of Fe and inevitable impurities. The manufacturing method comprises the following steps: performing smelting and casting of the components to obtain a steel ingot; adding the steel ingot into a radial forging machine heating furnace at 600-800 DEG C, heating to 1200-1230 DEG C with a heating speed of 60-120 DEG C/h, then performing thermal insulation for 3-5 hours; forging in a forging machine to obtain steel materials with an initial forging temperature of 1050-1100 DEG C and a final forging temperature of not less than 850 DEG C. After the obtained die steel is subject to quenching at 910-950 DEG C and tempering heat treatment at 160-200 DEG C, the impact toughness is above 135 J/cm2, and the hardness HRC is above 62.

The invention relates to a method for an optimized quenching process for obtaining 8Cr4Mo4V steel. The method comprises the following steps of (1) determining a heating solution process; (2) determining the time point of the highest hardness of isothermal hardening; (3) carrying out composite quenching treatment on the basis of the step (2); (4) selecting an optimized composite quenching process sample; and (5) carrying out tempering treatment on the optimized composite quenching process sample obtained in the step (4) at 510-550 DEG C for 1.8-2.5 h for 3-4 times, and obtaining the 8Cr4Mo4V steel subjected to final optimized heat treatment. The method has the advantages of scientificity, feasibility, simplicity in operation and the remarkable effect, and a space for improving the performance of the 8Cr4Mo4V steel is enlarged.

The invention provides a seamless steel tube and a preparation method of the seamless steel tube. Relative to the total weight of the seamless steel tube, the seamless steel tube is prepared from thefollowing components in percent by weight: 0.18-0.32% of C, 0.15-0.50% of Si, 0.35-0.65% of Mn, 0.40-0.85% of Cr, 0.50-1.00% of Mo, 0.05-0.15% of V, 0.01-0.05% of Al, less than 0.015% of P, less than0.003% of S and the balance Fe and inevitable impurities. By strictly controlling the chemical constituent contents of raw materials, the chemical components are reasonably proportioned, so that the strength, toughness and hydrogen sulfide stress corrosion resistance of the obtained seamless steel tube can meet the exploiting demands on high-pressure and high-temperature oil and gas fields in severe corrosive environments.

The invention relates to high-toughness cold-work mould steel and a preparation method thereof, belonging to the technical field of alloy steel manufacturing processes. The steel comprises the following chemical components in weight percentage: 0.5%-0.72% of C, 0.6%-0.8% of Si, 0.6%-1.0% of Mn, 2.0%-2.4% of Cr, 0.15%-0.25% of Mo, 0.1%-0.25% of V, 0.5%-0.8% of Ni and the balance of Fe. The preparation method of the cold-work mould steel comprises the following steps of: mixing the raw materials according to the a formula, smelting and pouring the batch mixtures in an induction furnace, and then carrying out electroslag remelting; and then forging and annealing, heating the mixtures to 850-930 DEG C for austenitization, and then carrying out secondary annealing at 180-200 DEG C after oil quenching to finally obtain the high-toughness cold-work mould steel. The cold-work mould steel has higher toughness matching and higher hardness and is a steel type suitable for manufacturing precise complex moulds.

The invention discloses Cu-reinforced Co-free secondary-hardening ultrahigh-strength steel and a preparation method, belonging to the technical field of alloy steel. The steel comprises the following chemical components in percentage by weight: 0.20-0.50% of C, 1.0-5.0% of Cr, 8.0-30.0% of Ni, 1.0-5.0% of Mo, 1.0-5.0% of Cu, 0-3.0% of Al, 0-2.0% of W, less than or equal to 0.30% of V, less than or equal to 0.20% of Nb and the balance of Fe and unavoidable impurities. According to the preparation method, the vacuum induction and vacuum consumable remelting technology or the vacuum induction and electroslag remelting technology can be adopted. Compared with the prior art, the Cu-reinforced Co-free secondary-hardening ultrahigh-strength steel has the advantages of good comprehensive performance, higher strength, good plasticity and toughness, good heat treatment process performance and higher tempering resistance and overaging resistance; the content of strategic resource Co element is saved and the economical efficiency is remarkably improved.

The invention discloses a method for the heat treatment of a 65Mn steel-made electronic scale sensor elastic body, which completes the heat treatment on a heat treatment continuous production line and which comprises the following specific steps: stamping molding material of the 65Mn steel-made electronic scale sensor elastic body is heated to 830 DEG C, quenching the material for 5 minutes in hot oil at 100 DEG C after heat preservation is performed for 15 to 30 minutes, then cleaning and drying the material; subsequently heating at 400 DEG C and preserving the heat for 80 minutes, followed by tempering; after the tempering, rapidly hydrocooling and drying, and detecting product; in the method according to the invention, the tempering temperature is raised to 400 DEG C, the resultant hardness is in a range of 43+/-1.5, so the demand of linearity can be met; plasticity and toughness of parts are enhanced by increasing the proportion of tempered sorbite; the method according to the invention rapidly hydrocools the material after tempering to prohibit harmful impurity elements such as P, S O, etc. in the material from grain boundary segregation, thereby suppressing temper brittleness.

A three-element (B, C and N) co-osmosizing process for metal surface includes such steps as loading the solid boronizing agent in carburizing furnace but isolating from the workpiece, dropping the co-osmosizing C-N liquid in the carburizing furnace, co-osmosizing at 780-880 deg.c and 0.15-0.2 mm/hr of speed, and cooling in oil or water. Its advantages are low co-osmosizing temp and quenching temp. less deformation of workpiece, and high effect on improving performance of workpiece.

The present invention provides a novel 9SiCrAlBN alloy tool steel, which contains C, Si, Mn, Cr, Al, B, Na, Mg, N and a nitride, wherein the improvement comprises that the tool steel comprises, by mass, 0.8-1.0 part of C, 0.3-1.8 parts of Si, 0.3-1.8 parts of Mn, 0.6-1.4 parts of Cr, 0-0.006 part of Na, 0-0.003 part of Mg, 0.8-1.8 parts of Al, 0-0.10 part of B, 0.01-0.10 part of N, 0.01-0.08 part of a nitride, and the balance of Fe and unavoidable impurities. Compared with the 9SiCrAlBN alloy tool steel in the prior art, the novel 9SiCrAlBN alloy tool steel of the present invention has the following excellent effects that: mechanical properties of the cold work mold steel Cr12 and Cr12Mo1V1 are maintained, a quenching temperature is substantially reduced, and a lot of energy sources are saved.

A joint outer ring (4) of a constant-velocity joint (1) has a stem portion (10) protruding from of a cup portion (9) and inserted to a through hole (31) of a hub (27) in a bearing device (2). The joint outer ring (4) has an abutment face (9aa) abutting against an end face of a bearing inner ring (28) fitted to an outer periphery of the hub (27) in an outer bottom face (9a) of the cup portion, and is composed of a forged product of a steel material. The joint outer ring (4) has a base material portion composed of a standard structure and an outer surface layer partially formed as a non-standard structure portion (30). The non-standard structure may be any one of an upper bainite structure, a lower bainite structure and a tempered martensite structure, or a mixed structure of at least two of the structures.

The invention discloses a surface induction hardening inductor for a V-shaped roller cross linear guide rail, which comprises an inducing conductor, a magnetizer and a fixing piece, wherein the inducing conductor made of a hollow copper tube adopts a door-type structure adapting to the cross section of the V-shaped roller cross linear guide rail; the magnetizer adapting to a V-shaped raceway surface of the V-shaped roller cross linear guide rail is arranged on the inducing conductor; and the fixing piece is arranged on the inducing conductor. The surface induction hardening inductor can achieve surface induction heating on the raceway surface and the bottom surface of the guide rail at the same time under different temperatures, different surface hardness and different hardening layer depths, ensures that a hardening layer with high hardness and high strength is formed on the raceway surface and the hardening layer has the bottom surface with certain hardness at the same time, and satisfies the requirements of quenching deformation of the guiding rail and the mounting hole processing.

The invention relates to smelting of metal components on a chute, and provides a high-manganese medium carbon steel wear-resisting chute lining plate. Steel materials are smelted through an electric-arc furnace and then transferred into a finery, the component proportion of the molten steel is adjusted, and then the steel is discharged. The molten steel is subjected to vacuum degassing and then full mold casting, and an obtained casting is subjected to heat treatment including water quenching and oil quenching to obtain a finished part. The components of the molten steel include, by weight, 0.54-0.58% of C, 12-16% of Mn, 1.5-3.5% of Cr, 2.5-3.5% of Al, 0.15-0.25% of Nb, 0.60-0.80% of Ti, 0.5-2.5% of B, 0.05-0.07% of Zr, less than 0.04% of P, less than 0.5% of Si and the balance Fe.

Novel 5CrW2SiBAlN shock-resisting tool steel is provided. The tool steel comprises C, Si, Cr, W, B, Al, Mg, N and nitrides (BN, AlN and/or TiN). An improvement of the tool steel is that: the tool steel comprises 0.40-0.60 part by mass of the C, 0.30-1.20 parts by mass of the Si, less than 0.40 part by mass of Mn, 1.00-1.60 parts by mass of the Cr, 2.00-3.00 parts by mass of the W, 0-0.008 part by mass of the B, 0-0.80 part by mass of the Al, 0-0.005 part by mass of the Mg and 0-0.10 part by mass of the N, with the total content of the nitrides being 0-0.80 part by mass and with the balance being Fe and unavoidable impurities. Compared with the prior art, beneficial effects of the novel 5CrW2SiBAlN are that the tool steel achieves mechanical performance of middle-chromium high alloy cold work die steel (with a code LD), largely reduces the quenching temperature and saves a large amount of energy.