8567results about How to "Grain refinement" patented technology

The invention relates to a high-conductivity aluminum alloy material for a cable and a preparation method thereof. The aluminum alloy material comprises the following components in percentage by weight: 0.25-0.80 percent of iron element, 0.02-0.15 percent of boron element, 0.1-1.5 percent of rare earth element and the balance of aluminum and inevitable impurities. The aluminum alloy is formed by adding an aluminum alloy intermediate alloy, an aluminum-boron alloy and an aluminum-rare earth intermediate alloy into an aluminum ingot of which the purity is more than 99.80 percent by weight and carrying out a casting process and annealing treatment on the mixture. Compared with a common electric aluminum conductor, the prepared aluminum alloy conductor has more excellent conductive performance and the conductivity reaching or exceeding 62.5 percent IACS (International Annealed Copper Standard); the aluminum alloy conductor treated by using a special process has excellent flexibility and creep resistance; and compared with a common electric aluminum conductor, the prepared aluminum alloy material used as a cable extrusion insulating lead core is more energy-saving and safer.

Disclosed is a titanium carbonitride based metal ceramic material based on a high-entropy alloy binder phase. The binder phase of the titanium carbonitride based metal ceramic material is high-entropy alloy, the hard phase of the titanium carbonitride based metal ceramic material is carbonitride solid solution, the high-entropy alloy binder phase includes at least four of ferrum, cobalt, nickel, chromium, aluminum, vanadium, titanium, copper, zirconium, molybdenum, manganese and rare earth elements, and the molar content ratio of each element ranges from 5% to 35%. In a preparation method, the titanium carbonitride based metal ceramic material based on the high-entropy alloy binder phase comprises raw materials including, in weight percent, 3-30% of the high-entropy alloy binder phase, 0-30% of second carbide powder and the balance carbonitride solid solution powder, the carbonitride solid solution powder includes at least one of Ti (Cx, N1-x), (Ti, M1...) and (Cx, N1-x), the M1 component of the (Ti, M1...) and (Cx, N1-x) includes at least one of W, Mo, Ta, Nb, V, Cr, Zr, Hf, Y and lanthanide, and 0<x<1 in the Ti (Cx, N1-x), (Ti, M1...) and (Cx, N1-x). The preparation method includes the process steps of (1) ball-milling mixing, (2) forming and (3) low-pressure sintering.

The invention discloses an oscillatory scanning laser beam-electric arc hybrid welding method and system. Laser beams and electric arc move together along an abutted seam in large range space, simultaneously the laser beams surround acting points of the electric arc to perform oscillatory scanning movement in a local small area, and an actual welding track is a curve formed by overlying two types of movements. As for an optimal range of laser beam oscillatory scanning displacement, the range in the direction of an X axis is minus 2mm to 3mm, the range in the direction of an Y axis is minus 5mm to 5mm, the range in the direction of a Z axis is minus 2mm to 2mm, and the oscillation frequency is in a range from 20Hz to 500Hz. According to the method and the system, an enhanced technical effect is achieved by the aid of interaction of a laser beam oscillatory scanning effect and a laser-electric arc synergistic effect, and the welding quality is improved. Compared with existing laser-electric arc hybrid welding and laser scanning welding methods and systems, the method and the system have the advantages that higher weld porosity inhibiting capability is achieved, and the weld strength is improved by 10% to 50%.

This invention is a high-intensive heat-fast magnesium alloy and its preparation method, and the magnesium alloy has the following components with their weight percentages: 6-15%Gd, 1-6%Y, 0.35-0.8%Zr, 0-1.5%Ca, and impurity elements Si, Fe, Cu and Ni with their gross less than 0.02%, and the rest percentage is Mg. while melting, add Gd, Y, Zr in the Mg melt in Mg-Gd, Mg-Y, Mg-Zr forms, then carry out solution treatment to the magnesium alloy under 450-500deg.C for 6-12 hours, squeeze in in 350-450deg.C, treat in time the squeezing stick for 10-16 hours in 225deg.C to improve its strength.

The invention discloses a method for manufacturing metal part solidification structure by a non-contact control added material and a magnetron metal 3D printing device. An electromagnetic field is applied in the quick solidification process of metal 3D printing; under the effect of the electromagnetic field, thermocurrent can be generated on a quickly solidified solid / liquid interface; the thermocurrent and the magnetic field are interacted to generate thermal electromagnetic force for triggering flowing of a melt; the end part of a dendritic crystal is shorn after suffering from the effect of the force to cause fragment of the dendritic crystal to form a lot of new crystal nucleus; and on the other hand, the temperature gradient of the front edge of the solid / liquid interface is slowed down through flowing of the melt, so that the constitutional supercooling of two phase regions is increased, the nucleation rate is increased. The method refines grains, improves the morphology of the grains, enables the structure to become uniform and compact, and realizes the structure control of metal 3D printing parts.

The invention discloses a close isothermal forging method of GH4169 alloy tray-shaped forging in the air, the technological process is that: making GH4169 finegrain roughcast adopting method of upsetting, punching and rolling after heating GH4169 alloy original rod material to 995-1005 DEG C; respectively heating the finegrain roughcast to 995-1005 DEG C and forging die to 950-965 DEG C; diefilling and positioning the finegrain roughcast; while heating finegrain roughcast and forging die to keep the heating warm humidity; forging die and forging press the finegrain roughcast forming under the 55MN to 65MN forging pressure and 0.01s-1 to 0.05s-1 strain rate; obtaining the tray-shaped forging; water-cool processing the tray-shaped forging. Adopting forging method of the invention can realize forming of the GH4169 alloy material tray-shaped forging difficult to deform and obtain the GH4169 alloy tray-shaped forging with weensy crystal grain, high intensity and complicated shape.

The invention relates to an ultrahigh-strength structural steel board for ocean engineering and a production method thereof, belonging to the technical field of ultrahigh-strength steel. A board blank comprises the following components: 0.05-0.13% of C, 0.1-0.4% of Si, 0.7-1.7% of Mn, 0.01-0.04% of Alt, 0.02-0.05% of Nb, 0-0.05% of V, 0.008-0.02% of Ti, 0-0.6% of Cr, 0.2-0.4% of Mo, 0.15-0.8% of Ni, 0-0.5% of Cu, 0-0.0011% of B, less than 0.01% of P, less than 0.005% of S, less than 0.0010% of O, less than 0.005% of N, less than 0.00015% of H, and the balance of Fe and inevitable impurities, wherein Nb+V+Ti is not more than 0.12%. Aiming at different thickness standards, different chemical component as well as rolling and heat treatment process parameters are adopted. The production process comprises the steps of molten iron desulfurization, converter top and bottom blowing, vacuum treatment, continuous casting, controlled rolling and controlled cooling, quenching and tempering. The steel board has the advantages that: the production cost is lower, and the comprehensive mechanical properties can meet the requirements of the steel for the ocean engineering for various mechanical properties.

The present invention is one kind of low alloy steel capable of being used in oil well pipe to resist CO2 and H2S corrosion. Chemically, its consists of C 0.01-0.30 wt%, Si 0.10-1.0 wt%, Mn 0.10-2.0, Cr 0.50-3.0 wt%, Mo 0.01-1.0 wt%, Ce 0.01-0.25 wt%, V 0.005-0.1 wt%, Cu 0.05-1.0 wt%, Al 0.01-0.10 wt% and small amount of Nb if necessary, except Fe and inevitable impurity, with impurity elements being less than 0.05 wt%. The alloy steel of the present invention after hardening and tempering has mechanical performance reaching the requirement on API 80 and 90 level steel but obviously improved CO2 and H2S corrosion resistance, and is economic oil well pipe steel with moderate cost.

The invention discloses a continuous casting process of an aluminum thin billet, which is characterized in that the following steps are included: aluminum alloy ingots are preheated and are melted in a melting furnace in the role of a flux; before casting, a side closure system is preheated to 400-450 DEG C, when the temperature of a melting body ranges from 650 DEG C to 680 DEG C, the aluminum alloy ingots are arranged into a tundish for 15 to 30 minutes in the role of the flux, then through a flux distributing device, the aluminum alloy ingots flow into an equant vertical twin-roll thin strip billet continuous caster, with a left forging seam gap being 0 mm and maintaining the height of a melting pool between 90 mm and 340 mm, the casting is carried out in a sinking way; when in casting, the casting speed of the casting machine ranges from 20 to 120m / min, the thin strip blank is sent into a pinch roll after leaving a casting roller, and the forged aluminum alloy thin strip has a thickness between 1.0 mm and 3.5 mm. The continuous casting process can directly make aluminum alloy thin strip blank from the liquid aluminum alloy, the forged thin strip blank has good quality on the surface, and the internal organizational structure is uniform, thereby being conducive to succeeding rolling processes. The continuous casting process for an aluminum thin blank has short process and low cost.

The invention relates to a refined crystal grain aluminum alloy and the manufacturing method. It is made up from Si 0.2-7.5wt%, Mn 0.05-1.5wt%, Mg 0,05-6.0wt%, Zn 0.03-8.5wt%, Cu 0.05-7.0wt%, Ni 0.1-2.5wt%, Ti 0.01-0.15wt%, RE 0.01-0.3wt%, B 0.0001-0.10wt%, and the rest is Al. The technology feature is that it adds silicon titanium alumina, borax and or rare earth oxide or rare earth carbonate, or titanium oxide, borax and / or rare earth oxide or rare earth carbonate into aluminum cell. Add the manganese oxide, compound of copper or Ni would be also added. Comparing to traditional technology, the refiner is not added, and the refining effect is enhanced and the perdurability is prolonged. It could be used to produce wire, band, tube, panel, aluminum foil, etc.

A lead-free alloy solder containing rare-earth elements and multiple other elements for electronic package contains Ag (0.1-5 wt.%), Cu (0.1-1 wt.%), Bi (0.1-8 wt.%), In (0.1-7.5 wt.%), Sb (0-8 wt.%), the mixture of La and Ce or the mixture of La, Ce and one or both of Pr and Nd (0.01-2 wt.%) and Sn (the balance). It has liquidus temp less than 210 deg.c (even 190 deg.C or lower), less than 15 deg.c for liquidus and solidus temp difference, at least 60 MPa of yield strength, at least 18% of elongation percentage, excellent wetting ability, and high soldering quality.

A cold rolling method for preparing high-Si steel sheet containing Fe (85-96 Wt%) and Si (4-15) includes such steps as providing raw material containing Si, B and Fe, smelting, casting, forging, hot rolling, warm rolling, heat treating and cold rolling.

The invention relates to a production process for an 82B wire rod used for a high strength prestressed steel wire and a wire rod thereof. The production process achieves objects of refining grains, improving the metallographic structure and obtaining high sorbite rate, improves strength and plasticity of the 82B wire rod used for the high strength prestressed steel wire and realizes an object of optimizing a metallographic structure and mechanical properties of the 82B wire rod used for the high strength prestressed steel wire, by optimally designing chemical components of the 82B wire rod used for the high strength prestressed steel wire, adjusting heating procedures of a heating furnace before rolling, and employing controlled rolling and controlled cooling techniques. The high power quality and mechanical properties of the 82B wire rod with a nominal diameter of 6.5 mm used for the high strength prestressed steel wire reach the national standard of the hot rolling wire rod used for the prestressed steel wire and steel strand, and meet production requirement of downstream users.

The invention discloses a disk-shaped roller cutter ring with high hardness, good toughness and excellent comprehensive performance. The disk-shaped roller cutter ring comprises the following ingredients of: 0.46-0.56% of C, 0.80-1.20% of Si, 0.20-0.65% of Mn, 5.00-5.80% of Cr, 1.15%-1.55% of Mo, 0.85-1.40% of V and the balance Fe and impurities, wherein the content of P is no more than 0.02%, and the content of S is no more than 0.01%; and the overall hardness of the cutter ring is HRC55-61 (Rockwell Hardness C55-61), or the hardness is of graded distribution, i.e. the hardness of a working edge area is HRC55-61, the hardness of a transition surface area is HRC50-57, and the hardness of a step assembly surface area and an inner ring is HRC44-51. A preparation method of the disk-shaped roller cutter ring comprises the following steps of: smelting the raw materials in an electric furnace; carrying out electroslag remelting; preforging; carrying out die forging; carrying out slow cooling; annealing; carrying out rough machining to obtain a disk-shaped roller cutter ring rough blank; carrying out high-temperature vacuum hardening and two-time high-temperature tempering on the cutter ring rough blank; carrying out low-temperature destressing treatment; carrying out fine finishing to obtain the cutter ring with the overall hardness of HRC55-61, wherein the cutter ring with the overall hardness of HRC55-61 is applicable to the tunneling of a hard rock formation by a shield tunneling machine; or carrying out medium-frequency induction tempering treatment prior to the low-temperature destressing treatment to obtain the cutter ring with graded-distribution hardness, wherein the cutter ring with the graded-distribution hardness is applicable to the tunneling of a rock formation with an upper soft part and a lower hard part.

The invention discloses an electromagnetic current coupling field assisted hybrid melting-brazing method for a laser-TIG arc and equipment. In addition to the use of the welding zone, an alternating magnetic field is added to control properties of plasma formed through ionization of laser, arc and a raw material metal, thereby improving the laser utilization rate. Under the electric field assisted comprehensive effect, the weld melting depth is increased, and the assistant effect on the melting bath of the liquid-state brazing filler metal for laser-arc melting-brazing is realized through electromagnetic stirring and excitation and enhancement, thereby promoting the orderly flow of the liquid-state brazing filler metal and the rupture, wetting, spreading and proliferation of the liquid-state brazing filler metal on the surface of the high metal material, improving the full mixing of the liquid-state brazing filler metal and the base metal formed by melting the low-melting-point metal material, improving the uniformity of the components of the brazed weld, stabilizing the welding process, reducing welding defects, increasing the welding speed, improving the weld formation, optimizing the structure and performance of the brazed weld, and improving the quality of the brazed joint. Moreover, the equipment has the advantages of simple structure, flexible application, low cost, good effect and easy realization.

The X65 pipeline steel for use in acid condition consists of C 0.02-0.05 wt%, Mn 1.20-1.50 wt%, Si 0.10-0.50 wt%, S not more than 0.0020 wt%, P 0.004-0.012 wt%, Nb 0.05-0.07 wt%, Ti 0.005-0.025 wt%, Mo 0.050-0.195 wt%, Cu not more than 0.35 wt%, Ni not more than 0.35 wt%, N not more than 0.0080 wt%, Ca 0.0015-0.0045 wt% and Ca / S not less than 2.0 except Fe. Its making process includes the following steps: smelting in a converter or an electric furnace; secondary steel making including LF desulfurizing + RH vacuum deairing and Ca treatment; continuous casting; rolling with initial rolling termination temperature of 940-1020 deg.c and finish rolling termination temperature of 780-840 deg.c; and winding at 500-580 deg.c. The X65 pipeline steel has low manufacture cost, high HIC resistance, high dynamic tear resistance and high impact toughness.

The invention belongs to the field of material surface engineering and more particularly relates to a method for carrying out cladding on a high-hardness wear-resistant anti-corrosion nickel-based alloy material on a metal substrate E in a large area by applying a laser cladding technology, solving the problem of cracks generated in the laser cladding process of the high-hardness wear-resistant nickel-based alloy, in particular the cladding defects, such as cracks with the thickness of more than 1mm, pores and the like during large-area cladding. According to the invention, the high-hardness nickel-based alloy powder material is cladded on the surface of the metal substrate in the large area to form a high-hardness wear-resistant anti-corrosion nickel-based alloy coating by applying the laser cladding technology and adopting a scientific and reasonable process method. According to the method disclosed by the invention, stability and consistency of laser cladding are foundationally ensured, defects, such as cracks, pores, impurities can be prevented from generating, heat affected regions of the substrate are reduced, dilution rate is reduced, the high-wear-resistance anticorrosion nickel-based alloy coating with firm metallurgical bonding and fine and compact grains is obtained and has the hardness reaching 58-63HRC, and the service life of the processed workpiece can be prolonged by more than 1-2 times.

The invention relates to a heat-resistant aluminum-alloy conductor material for cables and a manufacture method thereof. The aluminum-alloy conductor material is prepared from the following components in percentage by weight: 0.3-1.0 percent of Fe, 0.01-0.3 percent of Cu, 0.01-0.3 percent of Mg, 0.01-0.3 percent of one, two or three of Mg, Ca, Mo and Sb and 0.05-0.8 percent of one or more rear-earth elements of Sc, Y and Er, not larger than 0.1 percent of Si, not larger than 0.15 percent of other impurities and the balance of Al. The aluminum-alloy conductor material has excellent conductivity, tensile performance, flexible performance and excellent heat resistance, can be used as insulated cable cores of wires and cables and is particularly suitable for overhead insulated conductor wire cores.

The invention relates to an Alpha+Beta type titanium alloy steel bar fabrication technology used on a rotor vane, which comprises the following steps: (1) a cast ingot is heated, and the temperature is risen to 40 to 60 DEG C above a Beta transformation point after entering in a furnace, and the temperature is kept for 10 to 20 hours; (2) the cast ingot is processed through cogging and smithing, each pier drawing deformation amount is controlled between 30 percent to 40 percent; the smithing is performed in a two phase region after the pier drawing, and the total deformation amount is more than or equals to 90 percent; (3) the cast ingot is heated until the temperature reaches 20 to 40 DEG C above the transformation point after returning to the furnace, the temperature is preserved, and then the water quench is performed; (4) after the water quench, stocks are returned to the furnace and heated, and then are heat-preserved in the two phase region; the two phase region smithing is performed in a radial forging machine after the stocks reach a certain temperature, and the lengthening coefficient is controlled between 1.2 to 1.3; (5) after the radial smithing, the stocks is returned to the furnace and heat continuously and then is heat-preserved in the two phase region, then the stocks is rolled on a rolling mill, and the rolling temperature ranges from 910 to 940 DEG C. The Alpha+Beta type titanium alloy steel bar fabrication technology eliminates the figures on a macrostructure and the Beta spots on a microstructure of the heat strong two-phase titanium alloy caused by the hot work, and obtains a small-size two-phase titanium alloy steel bar with a fine and uniform equiaxed two-state structure.

The invention discloses automobile beam steel with tensile strength of 590MPa and a manufacturing method thereof. The steel comprises the following components in percentage by weight: 0.07-0.13 C, 0.10-0.30 Si, 1.30-1.60 Mn, at most 0.025 P, at most 0.008 S, 0.015-0.070 Al, 0.025-0.050 Nb, 0.020-0.040 Ti, and the balance of Fe and unavoidable impurities. The manufacturing method comprises the technical steps of molten iron desulfuration, bessemerizing, alloying, vacuum treatment, continuous casting, hot tandem rolling, Laminar cooling, reeling and finishing. Proved by practices, the automobile beam steel has stable chemical compositions and mechanical property as well as good cold forming performance and surface quality and completely meets the requirement for manufacturing novel frame structures of heavy-duty trucks and large vans.

The invention discloses a high-energy beam-ultrasonic composite additive manufacturing method for metal materials and belongs to the field of additive manufacturing (3D printing) of metal materials. The method comprises the steps that based on the technical principle of layer-by-layer accumulation of additive manufacturing, metal forming materials are melted through high-energy beams; after the metal forming materials are melted / solidified layer by layer to accumulate to a certain number of layers, the solidified layers are subjected to ultrasonic peening to have compressive plastic deformation, so the internal stress and the internal defects of formed parts are eliminated, and crystalline grains are refined; afterwards, the process of layer-by-layer melting / solidifying accumulation and the process of ultrasonic peening are continued until the whole forming process of metal members is completed. According to the method, real-time layer-by-layer treatment is performed on the solidified layers through ultrasonic peening, so the internal stress and the internal defects can be effectively reduced or eliminated, the crystalline grains can be refined, and the mechanical property of the metal members through additive manufacturing can be improved.

The present invention belongs to the field of steel-smelting technology. The steel consists of C 0.30-0.43 wt%, Mn less than 0.60 wt%, Si 0.70-1.00 wt%, P less than 0.010 wt%, S less than 0.007 wt%, Cr 4.50-5.50 wt%, Mo 1.00-1.50 wt%, V 0.7-1.00 wt%, Nb 0-0.25 wt%, Al less than 0.015 wt%, Ni 0.10-0.75 wt%, Cu less than 0.10 wt%, O less than 30 ppm and H less than 2 ppm, except Fe. It may contain one or several of RE, W, B, Ca, Mg, Zr and Ti. The steel of the present invention has reasonable production process, high performance and long service life of the core rod therewith.

The invention discloses a high-hardness hypereutectic high Cr-Mn-Mo-tungsten alloy abrasion-resistant steel and iron material which adopts multivariant alloying and has the advantages of good hardenability, high hardness, better abrasion-resistance and wear resistance, and the like compared with the prior high-chromium cast iron especially the addition of C, Cr, Mn, Mo and tungsten, thereby enlarging the application range of materials. The invention is suitable for preparing wearing and corrosive wearing parts, in particular to parts used for impacting corrosive wearing working conditions.

The invention relates to a medium strength aluminium alloy wire with conductivity of 60% IACS, and a preparation method thereof, and belongs to the field of alloy manufacturing technology. The alloy elements comprise, by weight, 0.16%-0.22% of iron, 0.24%-0.30% of silicon, 0.40%-0.48% of magnesium, 0.01%-0.02% of boron and 0.08%-0.15% of a rare earth element, with the balance being aluminium. The medium strength aluminium alloy wire with a product conductivity higher than or equal to 60% IACS and tensile strength higher than or equal to 230 MPa is obtained by processes of selecting materials, smelting liquid aluminium, adjusting liquid aluminium ingredients, carrying out purifying treatment, deslagging, standing with heat preservation, degassing, filtering with heat preservation, casting and crystallizing, rolling an aluminum rod, drawing and aging. The wire and cable produced by using the aluminium alloy can be erected continuously by a conventional construction process. In a circuit operation process, circuit loss can be reduced; construction fee can be reduced; and the medium strength aluminium alloy has significant economic benefits and social benefits.

The invention provides an added material manufacturing device and a method. The device is characterized by comprising an added material machining part, a high-speed camera part, an infrared temperature measuring part, an optical measuring part, an internal defect detecting part, an aftertreatment part and a control part, wherein the high-speed camera part comprises a camera head, which moves withthe added material machining head at the same time to obtain material image information; the infrared temperature measuring part comprises a temperature measuring head, which moves with the added material machining head at the same time to obtain material temperature distribution information; the optical measuring part detects surface defects and forming sizes of materials to obtain detecting information; the internal defect detecting part comprises a detecting head and a detecting analyzer; the aftertreatment part treats material defect areas to eliminate defects by adopting corresponding aftertreatment modes; the aftertreatment modes comprise at least one of mechanical rolling treatment, laser shock reinforcement treatment and friction stir treatment; and the control part controls all the parts to operate to obtain various information, determines the defect treatment areas, aftertreatment paths and the aftertreatment modes based on the information, and controls the aftertreatment part to perform corresponding aftertreatments.

The invention relates to a smelting method for medium-thin wall cast-state nickel-free low-temperature ductile cast iron. The medium-thin wall cast-state nickel-free low-temperature ductile cast iron comprises the following chemical components in percentage by mass: 3.5-4.1 percent of C, 1.7-2.2 percent of Si, 0.10-0.25 percent of Mn, not more than 0.035 percent of P, not more than 0.020 percent of S, 0.015-0.030 percent of Re, 0.025-0.045 percent of Mg, 0-0.20percent of Cu, less than 0.1 percent of residual element, and Fe in balancing amount. The medium-thin wall cast-state nickel-free low-temperature ductile cast iron is obtained by mixing furnace materials and carrying out high-temperature smelting in an intermediate-frequency furnace, modularization and inoculation treatment and casting and heat-insulating treatment on the mixed furnace materials. Cast iron products obtained by adopting the smelting method disclosed by the invention obtain normal-temperature mechanical property and low-temperature mechanical property under the cast state conditions; complex medium-thin wall parts are required to be subjected to low-temperature stress relief annealing; and simple medium-thin wall parts are free from being annealed, so that the production cost is greatly reduced, the production period is greatly shortened and the production efficiency is increased.

The invention relates to a controlled-forging controlled-cooling processing technology of a bearing ring prepared by GCr15, comprising the following steps of: quenching the bearing ring in cooling fluid at final forging temperature of 850-950 DEG C and at fluid outlet temperature of 350-550 DEG C; when heating the bearing ring to the temperature of 450-550 DEG C, after preserving the temperature for 1h-3h, discharging the bearing ring from a boiler and cooling the bearing ring to room temperature; when heating the bearing ring to the temperature of 650-690 DEG C again, preserving the temperature for 1h; when continuously heating the bearing ring to the temperature of 740-780 DEG C, after preserving the temperature for 2-3h, cooling the bearing ring to the temperature of 680-690 DEG C and preserving the temperature for 2-4 hours; finally, when cooling the bearing ring to the temperature of 550-600 DEG C at the speed of 10 DEG C / h, cooling o the bearing ring to the room temperature along with the boiler by air; quenching a machined semi-finished bearing ring; when heating to the temperature of 810-830 DEG C, after preserving the temperature for 45-60min, discharging the machined semi-finished bearing ring from the boiler and quenching the machined semi-finished bearing ring in oil; and when heating the machined semi-finished bearing ring to the temperature of 160-200 DEG C after being quenched, preserving the temperature of the machined semi-finished bearing ring for 4h, discharging the machined semi-finished bearing ring from the boiler and cooling the machined semi-finished bearing ring to the room temperature by air. According to the invention, carbides, martensite crystals and austenite crystals of the bearing ring are refined, network carbides are improved or eliminated and impact ductility and fatigue life are improved.

The invention discloses a plastic mold steel which comprises the following chemical components in percentage by weight: 0.25-0.29% of C, 1.30-1.50% of Mn, 0.40-0.60% of Si, 1.20-1.50% of Cr, 0.40-0.50% of Mo, 0.02-0.05% of Nb, less than or equal to 0.15% of Ni, less than or equal to 0.15% of Cu, less than or equal to 0.020% of P, less than or equal to 0.015% of S, less than or equal to 0.012% of N and the balance of iron and inevitable impurities. In the manufacture method of the plastic mold steel, a quenching and tempering heat treatment process is not used, and direct air cooling after forging is carried out, thus prehardened plastic mold steel with thickness above 600 mm and uniform hardness from core to surface is manufactured. According to the plastic mold steel disclosed by the invention, the limit that the existing non-quenched and tempered mold steel has thickness smaller than 400 mm is overcome, and the requirements of mold industries on low-cost high-quality large-sized prehardened plastic mold steel are reached.

A medical Mg-Zn-Ca alloy material absorbable in biologic body is proportionally prepared from high-purity full-nutritive Mg and Zn to form MgZn phase for high strength and anticorrosion nature, and Ca for fining grains for high strength and plasticity. It has high biocompatibility and mechanical performance and can be used for intravescular scaffold, bone nail, bone plate, etc.

The invention relates to a method for refining a solidified structure of a laser cladding layer by using an alternating magnetic field and a device thereof, belongs to the technical field of laser processing. A compound coating is prepared on the surface of a substrate in a manner of conventional powder-feed laser cladding; the alternating magnetic field is applied to acting on a laser molten pool during the laser cladding; the powder-feed laser cladding process is carried out under the alternating magnetic field; and the direction of magnetic lines of force generated by the alternating magnetic field is perpendicular to the scanning speed direction of the laser cladding. The device for refining the solidified structure of the laser cladding layer by using the alternating magnetic field comprises a cooler, a CO2 laser, an argon protector, a synchronous powder feeder, a clamping device, an alternating magnetic field, a cladding substrate body and a numerical control operation floor. The method and the device provided by the invention are capable of obviously refining the solidified structure of the cladding layer; when alternating current with certain frequency is introduced into a coil, an alternating magnetic field can be generated between a metal melt and the magnetic field coil; and the intensity of the alternating magnetic field is controlled so as to change a form of the solidified structure of the cladding layer and refine crystalline grains through changing the intensity of an alternating magnetic field. The device provided by the invention is simple, low in investment cost, high in benefit, etc.