42results about How to "Good heat treatment performance" patented technology

The invention provides a critical solid solution and critical multiple cooling variable temperature aging and annealing composite heat treatment method. The method comprises a critical solid solution heat treatment process and a critical multiple-cooling variable-temperature aging and annealing composite heat treatment process. According to the scheme, the problems that existing austenitic stainless steel heat treatment is poor in quality stability, low in qualified rate, low in hardness, low in mechanical property, poor in consistency, poor in discoloration and corrosion resistance, long in heating time, low in efficiency, low in cost and the like can be solved. The heating reliability of heat treatment equipment is poor; the service life of a high-temperature component is short; the cost is high; and the like.

The invention provides an inner conical elastomer for a strain force transducer. The inner conical elastomer comprises a cylindrical base body; the upper part of the base body is provided with a conical concave part; the bottom of the conical concave part is provided with a central hole; and the conical surface of the conical concave part is provided with a strain gauge. The optimization method for the elastomer comprises the following steps of: estimating an initial size; calculating stress of the elastomer under the action of the axial force of a bolt by a finite element method, and adjusting the cone angle of a model until stress on the inner conical surface is distributed uniformly; adjusting the thickness of the base body under the condition of not changing the cone angle to ensure that the stress level on the conical surface meets the requirement; and rounding the model size obtained through finite element calculation, wherein the rounded model size is used as the final size of the elastomer. The inner conical elastomer is a simple revolution solid, and is high in processing and heat treatment manufacturability; the stress of the adhesion part of the strain gauge is distributed uniformly; and the accuracy of the adhesion position of the strain gauge is not required. The axial size of the elastomer is smaller than that of a spoke elastomer, and the elastomer is more suitable for measuring the axial force of the bolt.

The invention provides a rapid solid solution and rapid cooling and heating aging heat treatment method. The method comprises a rapid solid solution heat treatment process and a rapid cooling and heating aging heat treatment process. According to the scheme of the method, the specific heat treatment technical problems of poor quality stability, a low qualified rate, a low hardness, a low mechanical property, poor consistency, long heating time, low efficiency, poor heating reliability of heat treatment equipment, a short service life of high-temperature components, high cost and the like in heat treatment of austenitic stainless steel can be solved.

The invention discloses a carbonitriding heat treatment technique under a new atmosphere. The technique comprises the following steps that (a), a multi-purpose chamber furnace suitable for carburizing treatment is selected; (b), a nitrogen, methyl alcohol, ammonia gas and dimethylmethane carburizing medium is adopted, and an oxygen probe is adopted to control the carbon potential, so that control over the carbon potential of the atmosphere in the furnace is achieved; (c), according to a charging mode, charging layers are chosen according to the heights of workpieces, and gaps are kept between the workpieces of each layer to guarantee the uniformity of infiltration layers; (d), according to technological parameters, the carbonitriding temperature is 815 DEG C-825 DEG C, the carbon potential is 1.20%-1.30%, and strong infiltration is conducted for 3 h-3.5 h; in the diffusion period, the temperature is 815 DEG C-825 DEG C, the carbon potential is 1.10%-1.20%, and diffusion is conducted for 3 h-3.5 h; KR-218 fast bright quenching oil is used for quenching, and cooling is conducted for 8 min-15min; and air cooling is conducted after tempering; and (e), steel foil is used for carbon determination during strong infiltration of each furnace. According to the carbonitriding heat treatment technique under the new atmosphere, a carbonitriding layer with a certain depth can be obtained in a relatively short time, and higher hardness is achieved.

The invention discloses Co-free composite reinforced secondary hardening ultrahigh-strength steel and a preparing method and belongs to the technical field of alloy steel. The Co-free composite reinforced secondary hardening ultrahigh-strength steel comprises, by weight, 0.20-0.50% of C, 1.0-5.0% of Cr, 10.0-30.0% of Ni, 0.50-3.0% of Al, 1.0-5.0% of Mo, 2.0% of W or less, 0.30% of V or less, 0.20% of Nb or less, and the balance Fe and unavoidable impurities. The vacuum induction technology, the vacuum arc remelting or vacuum induction technology and the electroslag remelting technology can be adopted in the alloy. Compared with the prior art, the Co-free composite reinforced secondary hardening ultrahigh-strength steel has the beneficial effects that the comprehensive performance is good, ultrahigh strength and good ductility and toughness are achieved, the heat treatment technology is superior in performance, high temper resistance and overaging resisting capability are achieved, the content of the strategic resource of the Co element is saved, and the economical efficiency is improved.

The invention discloses a roller sleeve for large forged alloy steel carrying roller and a manufacturing method thereof. The roller sleeve for large forged alloy steel carrying roller comprises following chemical constituents in percentage by mass: 0.40-0.80% of C, 0.20-1.20% of Si, 0.20-1.00% of Mn, 3.00-8.00% of Cr, 0.15-1.50% of Mo, 0.05-0.40% of V, Ni<=0.80%, P<=0.02%, S<=0.02% and the balance of Fe and ineluctable impurities. The manufacturing method for the roller sleeve for large forged alloy steel carrying roller comprises four steps, including refining steel ingot, forging roller sleeve base, pre-heating and machining and final heat treatment. The product of the invention is excellent in anti-contact fatigue performance, abrasion performance and roller shape retention, so that a complex carrying roller can satisfy rolling requirements of high-accuracy plates. According to the invention, the complex carrying roller obviously precedes conventional carrying rollers in contact-fatigue performance, roller shape retention and anti-mechanical and anti-thermal impact performances, and has especially excellent performance when being used as a sleeve for a convexity-changeable complex carrying roller.

The invention relates to a high-performance heat-resistant cast magnesium alloy and a preparation method thereof. The magnesium alloy comprises the following components in percentage by mass: 5-8% of Zn, 1.5% of Si, 3% of Sn, 0.5% of Sr, 0.5% of Bi and the balance of Mg. The method comprises the following steps: preparing raw materials according to the mass percent; smelting Mg with an iron crucible in a crucible resistance furnace until the Mg is molten, adding Zn, Si, Sn, Sr and Bi, smelting at 720-750 DEG C by using an N2-SF6 gas mixture as a protective gas, and casting the obtained liquid metal at 730 DEG C; and carrying out solid solution on the obtained cast ingot at 350 DEG C for 24 hours, heating to 450 DEG C, carrying out solid solution for 12 hours, and aging the cast ingot at 200 DEG C for 36-60 hours. The room-temperature tensile strength of the obtained high-performance heat-resistant cast magnesium alloy is greater than or equal to 320 MPa, and the percentage of elongation is greater than or equal to 6%. The tensile strength at 200 DEG C is greater than or equal to 220 MPa, and the percentage of elongation is greater than or equal to 9%. The high-performance heat-resistant cast magnesium alloy has favorable comprehensive mechanical properties, and can be widely used in commercial parts, including automobile parts, electronic product components and components for aviation and aerospace.

The invention provides a critical solid solution and critical heating aging heat treatment method. The critical solid solution and critical heating aging heat treatment method comprises a critical solid solution heat treatment process and a critical heating aging heat treatment process. The scheme has technical feasibility, process adaptability, quality reliability, economic rationality and use safety, and can effectively enhance the advantages and avoid the disadvantages of a traditional mainstream heat treatment method of austenitic stainless steel; the problems that existing austenitic stainless steel heat treatment is poor in quality stability, low in qualified product rate, low in hardness, low in mechanical property, poor in consistency, poor in discoloration and corrosion resistance, long in heating time, low in efficiency, heat treatment equipment is poor in heating reliability, high-temperature components are short in service life, the cost is high, and other special heat treatment technology problems are fundamentally solved. The method is particularly suitable for the technical field of hot working engineering such as smelting, steel rolling, forging and heat treatment related to the austenitic stainless steel in steel mills and manufacturers.