68results about How to "Reduce quenching stress" patented technology

The invention discloses high strength strapping steel with tensile strength over 1,100 MPa and a manufacturing method thereof. The high strength strapping steel comprises the following components in percentage by weight: 0.25 to 0.35 percent of C, 1.0 to 2.0 percent of Mn, less than or equal to 0.45 percent of Si, less than or equal to 0.04 percent of S, less than or equal to 0.04 percent of P, and the balance of Fe and inevitable impurities. The manufacturing method comprises a steel smelting process, hot rolling process, cold rolling process and ferrite-austenite two-phase region quick quenching and annealing heat treatment process for smelting pure steel while controlling the state of impurities. The method can realize the excellent combination of strength and plasticity, realizes the clean production of the high-strength strapping steel which has a tensile strength over 1,100MPa and an elongation over 10 percent, and has the advantages of easy-to-implement production operation, high production efficiency, low production cost, light environmental pollution. Thus, the method has a good application prospect.

The invention discloses a slitting cutting disc and a preparation method thereof, which belong to the process field of cutters. The slitting cutting disc is of a circle blade, and comprises a center hole, a cutter disc and a blade, wherein the center hole is arranged in the center of the cutter disc, the blade is arranged on an outer ring of the cutter disc, a blade opening is arranged on an outer ring of the blade, and the opening angle delta ( ) of blade opening is 23-27 degrees. The opening thickness h of the blade opening is 0.24-0.26mm. The materials which are made into the slitting cutting disc comprise components with percentage by weight: carbon (C) 1.15-1.33%, nitrogen (N) 0.2-0.4%, manganese (Mn) 0.30-0.40%, silicon (Si) 0.52-1.20%, chromium (Cr) 8.50-10.50%, tungsten (W) 1.50-2.50%, vanadium (V) 0.35-0.50%, molybdenum (Mo) 0.25-0.4%, nickel (Ni) 0.30-0.40%, copper (Cu) <=0.30%, sulphur (S)<=0.020% and phosphorus (P)<=0.027%, and the allowance is ferrum (Fe). The slitting cutting disc has the advantages that the slitting cutting disc is excellent in abrasive resistance and is not easy to deform, and the blade opening resists abrasion, not easy to crack, long in service life and easy to make.

The invention relates to a process for carrying out heat treatment on spring steel PAG of an automobile steel plate spring SiMn system through a water-soluble quenching medium. The process utilizes the reversibility of an aqueous solution of a PAG polymer; when hot metal is immersed and quenched in quenching liquid, a coating layer enclosed by the metal-rich PAG polymer controls the radiation speed of the surface of the metal; the aim of the process is to solve the increase of hardenability of the spring steel of the SiMn system with thick specification in quenching, thereby ensuring that large quench hardening depth is obtained in quenching while the thermal stress and the structural stress of a workpiece are smallest.

The invention relates to a composite carburizing and quenching heat treatment method of a gear, and belongs to the technical field of heat treatment. The method comprises the steps of carburization, cooling, heating, quenching and tempering. The composite carburizing and quenching heat treatment method can effectively refine grains and martensite needles, improves the gear surface hardness, further improves the wear resistance, the fatigue strength and the corrosion resistance of the gear, and improves comprehensive mechanical performance of the gear.

The invention discloses a quenching-tempering heat treatment method for large-scale module die steel. The method comprises the following steps of carrying out heating; carrying out heat preservation;carrying out water-cooling and air-cooling alternate quenching multiple times; and carrying out high-temperature tempering. The method has the advantages that a water-quenching air-cooling mode is adopted, water-lifting air-cooling is carried out multiple times, self-tempering is carried out, the surface structural transformation stress is eliminated, the cooling strength is within oil quenching and water quenching, and therefore through quenching of a large-scale module is ensured, and meanwhile, water-quenching cracking is avoided; the perlitic transformation caused by water quenching is avoided, then water lifting is carried out multiple times to decrease the cooling speed, so that the quenching stress is decreased, and therefore the cooling speed of a high-temperature section is increased, and meanwhile, quenching cracking is also prevented; and when the temperature of martensite cooled to 1.2738 begins to change temperature, air cooling is carried out, so that the forming speed ofthe martensite is decreased, and therefore the structural stress can be greatly decreased, and cracking of a low-temperature section can be avoided.

The invention discloses an isothermal transformation thermal treatment method for superhigh-intensity steel, which comprises the following steps of: directly quenching rolled steel material, wherein the initial quenching temperature is 850-900DEG C, and the final quenching temperature is 150-250DEG C; preserving the temperature of the quenched steel material for 0.1-0.5min/mm, wherein the mm is the unit of the thickness or the radius of the steel material; heating and tempering the steel material of which the temperature is preserved, wherein the on-line tempering temperature preservation temperature range is 200-350DEG C, the tempering temperature preservation time is 2-6min/mm, and the mm is the unit of the thickness or the radius of the steel material; and after tempering treatment, cooling the steel material to the room temperature.

The invention discloses a niobium micro-alloyed wear-resisting cast steel material, application thereof and a preparation method thereof, and the niobium micro-alloyed wear-resisting cast steel material is suitable for manufacturing a niobium alloying effect based wear-resisting cast steel part of a ball mill lining plate. The niobium micro-alloyed wear-resisting cast steel material comprises alloy components, and a thermal treatment process, and belongs to the technical field of metal material processes. The niobium micro-alloyed wear-resisting cast steel material consists of the following components in percentage by mass: 0.45-0.55% of C, 0.95-1.05% of Si, 1.5-1.6% of Mn, 4.2-4.8% of Cr, 0.75-0.80% of Mo, 0.15-0.20% of Nb, less than or equal to 0.02% of S, less than or equal to 0.03% ofP and the balance of Fe. An element niobium is added to obtain fine discontinuously-distributed niobium carbide, so that the effects of solid solution strengthening and grain boundary pinning are achieved, and therefore, hardness, impact toughness and tensile strength of the material are matched and improved very well, a wear-resisting lining plate material with stable performance is obtained under an air-cooling way, and the process is simple and environmentally friendly.

The present invention discloses a chromium-molybdenum low-alloy zinc-plating steel strand manufacturing method, wherein the chromium-nickel-molybdenum alloy structure steel comprises, by mass, 0.28-0.38% of carbon, 0-0.35% of silicon, 0-0.90% of manganese, 0.80-1.50% of chromium, 3.00-4.00% of nickel, 0.40-0.60% of molybdenum, 0-0.015%of phosphorus, 0-0.015% of sulfur, 0-2.0 ppm 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. According to the chromium-molybdenum low-alloy zinc-plating steel strand manufacturing method designed by the present invention, the prepared chromium-molybdenum low-alloy zinc-plating steel strand has characteristics of high strength, good hardenability good, cracking resistance, low relaxation degree, and smooth and uniform surface zinc plating.

The invention discloses a cold rolling roller with an ultra-deep hardening layer and a manufacturing method of the cold rolling roller. The cold rolling roller comprises, by mass, 0.85%-0.95% of C, 0.60%-0.80% of Si, 0.60%-0.80% of Mn, 4.80%-5.80% of Cr, 0.30%-0.50% of Ni, 0.40%-0.60% of Mo, 0.05%-0.15% of V, 0-0.015% of P, 0-0.015% of S, and the balance Fe and inevitable impurities. The manufacturing method of the cold rolling roller comprises the process steps of smelting quenching and tempering, finish heat treatment and the like. The surface hardness of the manufactured cold rolling roller is 92-99 HSD, the hardening layer with the hardness being over 90 HSD is over 45 mm in depth, and the cold rolling roller is provided with the ultra-deep hardening layer.

The invention provides a heat treatment process of alloy spring steel. The process comprises the steps of performing preheating, heating, isothermal spheroidizing annealing, quenching, cooling, medium-temperature tempering, two times of shot blasting treatment and processing inspecting on a steel billet. According to the method, the temperature of isothermal spheroidizing annealing is controlled to be 650-700 DEG C, and the annealing time is 2-3 hours, so that the phenomenon that part of carbide cannot be fully spheroidized is avoided, the hardness of the spring steel is reduced to 32-48 HRC,the problem that deforming or cracking is prone to occur in subsequent heat treatment is solved, the corresponding tensile strength is reduced to 1810-1930 MPa, the using stress amplitude is improvedby 10 %-15 % compared with that of spring steel prepared through a traditional technology, and the novel spring steel has higher ductility and toughness; the quenching temperature is controlled to reduce the quenching stress and reduce the deformation, so that a high yield ratio and good comprehensive mechanical properties are obtained; and the cooling mode is controlled, and the two times of shotblasting treatment is adopted, so that the surface of the spring steel is strengthened, the surface quality of the spring steel is improved, the residual compressive stress is generated on the surface, and the the spring steel is improved in fatigue strength and prolonged in service life.

The invention discloses a manufacturing method of a high-yield non-bonding prestress steel bar. The steel bar has the advantages of bringing convenience to manual construction, being low in cost, high in strength, good in ductility and high in delayed fracture and saving steel, has ideal insulation effects, and can reduce environment pollution. According to the manufacturing method, steel structure anticorrosive paint is adopted, good mechanical performance and excellent anti-corrosion performance are achieved, stability for weather, oil water mixtures and the like is good, various colors can be mixed according to needs, the steel bar can have good visual effects after the steel anticorrosive paint is used, attractiveness and elegance in decoration are achieved, and cost can also be saved due to the fact that the paint has long anti-corrosion time.

The present invention discloses 600 MPa-grade-and-above high strength steel bars and a reinforced concrete application method thereof. According to the present invention, 0.4-0.65% by weight of Mn, 0.6-0.7% by weight of Cr, 0.15-0.3% by weight of Mo, 0.5-0.65% by weight of Ni, and 0.25-0.4% by weight of V are added to the steel bar component so as to improve strength, toughness, corrosion resistance, wear resistance and impact resistance of the steel bar, make the steel bar be compact, improve hardenability of the steel, and improve atom activities of the elements such as C and N, such that deformation and cracking can be reduced; and the application method of the diameter 6 mm and diameter 22 mm 600 MPa-grade-and-above high strength steel bars in the reinforced concrete has advantages of steel bar consumption reduction, carrying capacity increase, and crack extension resistance.

The invention discloses a heat treatment deformation control method for a 23Co14Ni12Cr3MoE steel large part. The heat treatment deformation control method comprises the steps of stress relief tempering, gas-cooled quenching, ice-cold treatment, low-temperature tempering, correction, final tempering and the like. According to the heat treatment deformation control method, vacuum gas-cooled quenching is adopted to replace oil-cooled quenching with a relatively high cooling speed, the hardness, tensile strength, yield strength, fracture toughness and the like of the part after heat treatment allmeet the technical standard requirements, moreover, the generation of quenching stress can be reduced, the part is basically not deformed after heat treatment, and the size precision meets the designrequirements.

The invention relates to an isothermal quenching heat treatment process method for third-generation bearing steel. The isothermal quenching heat treatment process method comprises the following stepsthat A, solution treatment is carried out; B, isothermal quenching is conducted, specifically, when the thickness h of a steel block is smaller than or equal to 20 mm, constant-pressure and constant-flow-speed gas quenching is adopted, specifically, the pressure is 0.2-1.5 MPa, the flow speed is 0.1-0.8m/s, the cooling time is smaller than or equal to 15 min, the cooling speed is 60-100 DEG C/min,and heat preservation is conducted for 1-2 h after the steel block is cooled to the isothermal temperature of 140-280 DEG C; then air cooling is carried out to room temperature; and when the thickness h of the steel block is larger than 20 mm and smaller than or equal to 50 mm, high-pressure high-flow-speed gas quenching and low-pressure low-flow-speed gas quenching are adopted for segmented circulating cooling. By adopting the isothermal quenching heat treatment process, the plasticity and toughness of the third-generation bearing steel can be improved, so that the structure components are uniform and environment-friendly.