35results about How to "Uniform fine grain structure" patented technology

The invention discloses a composite molybdenum wire used for linear cutting and a manufacturing method. The composite molybdenum wire is made of molybdenum powder containing solid solution metal elements and rare earth oxide. The solid solution metal elements are selected from at least one of Co, W, Ni, Hf or Re, and the weight content of the solid solution metal elements is 0.01%-0.30%. The rare earth oxide is selected from at least one of La2O3 or Y2O3, and the weight content of the rare earth oxide is 0.005%-0.20%. The manufacturing method comprises the following steps that secondary solid-liquid mixing is conducted, and uniform mixed molybdenum powder is obtained; then a molybdenum rod billet is obtained through pressing; the sintered molybdenum rod billet is rolled into a molybdenum coil rod; then the composite molybdenum wire used for linear cutting is obtained through drawing by repeatedly conducting a hot draw technique and a cold draw technique; and annealing is conducted repeatedly in the process, and the composite molybdenum wire is obtained. According to the composite molybdenum wire used for linear cutting, the abrasion resistance can be substantially improved, the service life is longer during cutting, the cutting speed is higher, and the rate of finished products is larger.

A microwave oven sintering preparation method of silicon nitride ceramic heating body and the special equipment belong to the field of preparation process of electric heating body and the special equipment. The present invention is characterized in that the special equipment comprises a microwave oven body, a crucible, a fiber insulation body on the outside layer and an insulation body on a secondary outer layer, a special insulation body for sintering consisting of an assistant heating plate and a fiber insulation ball filling layer. The preparation method is as follows: a ceramic green compact is put into a crucible; then the corundum crucible filled with the ceramic green compact and the special insulation bodies for sintering are together put into a microwave sintering device for sintering. The sintering process is as follows: the inside of the microwave oven is first vacuumed; the N₂ of quality percent of more than 90 percent is filled; the procedures are repeated a plurality of times; the temperature-raising program is arranged to be adjustable between 5 DEG C per minute to 50 DEG C per minute; the temperature is raised to be 1300 plus or minus 50 DEG C and kept for 10 to 60 minutes; then the temperature is raised to be between 1600 and 1750 DEG C and kept for 5 to 60 minutes; the microwave source is closed and the product is naturally cooled.

The invention provides a wear-resisting hammer head for a hammer type breaking machine. The wear-resisting hammer head comprises a high-manganese-steel lifting lug and a high-chrome iron hammer head body. The production method comprises smelting, modification treatment, casting and heat treatment. The hammer head produced through the method has the higher hardness and wear resistance, and wear of the hammer head in the using process is reduced; toughness of the hammer head can be obviously improved, and good bonding of hardness and the toughness is ensured; and the phenomenon that due to higher brittleness, the hammer head is broken in the using process is avoided.

The invention provides a preparation method for a titanium, aluminum and silicon alloy target. The method comprises the steps: alloy powder preparation, cold isostatic pressure treatment, degassing treatment, thermal isostatic pressure treatment and machining. The titanium, aluminum and silicon alloy target prepared by the preparation method disclosed by the invention has the advantages of high compactness, no gas hole and segregation, uniform tissue, small crystalline grain and the like, and is suitable for sputtering coating layers of various cutters and dies.

The invention discloses a method for preparing a large-specification difficult-to-deform high-temperature alloy fine crystal bar, and belongs to the technical field of high-temperature alloy hot machining. The method comprises the following steps of ingot casting machining; ingot upsetting; intermediate billet sheathing; hot extruding; and extrusion bar machining. According to the method, a billetmaking method that the cogging deformation is enabled to be increased through the upsetting and extruding and optimizing deformation distribution is provided, the method can be used for preparing thelarge-specification difficult-to-deform high-temperature alloy uniform and fine crystal rod, and meet the development requirements of a difficult-to-deform nickel-based high-temperature alloy turbinedisc forging piece.

The invention discloses a preparation method of an ultralow-temperature TA7ELI titanium alloy plate. The method comprises the following steps: (1) a TA7ELI titanium alloy plate blank is heated for thefirst time; (2) the TA7ELI titanium alloy plate blank is rolled as a first semi-finished plate blank after primary heating; (3) the first semi-finished plate blank is formed to a second semi-finishedplate blank through polishing, acid washing and cutting in sequence; (4) the second semi-finished plate blank is heated for the second time; (5) the second semi-finished plate blank is rolled as a second semi-finished plate blank after secondary heating; and (6) the second semi-finished plate blank is straightened after insulation, and is cooled in air to reach the room temperature to obtain theTA7ELI titanium alloy plate. The high-temperature heating treatment and the reversing rolling method are adopted to provide larger deformation space for twin deformation, in the leading deformation role, of the plate under ultralow temperature; and the plate blank structure uniformity is promoted to obtain the ultralow-temperature TA7ELI titanium alloy plate.

The invention relates to an isothermal die forging technology for large-size high-strength aluminum alloy parts, and belongs to the technical field of aluminum alloy machining. According to the isothermal die forging technology, large-size aluminum alloy forging cake blanks undergo isothermal die forging formation in one step after being heated and thermally insulated for obtaining forge pieces, the forge pieces are taken out and cooled, and finally finished products are obtained; in the isothermal die forging process, the descending speed of upper dies is 0.1-0.2 mm/s. By selecting raw materials and strictly controlling forging parameters, continuous large deformation is realized on the condition that alloy crystal grains do not grow, and the large-size and high-performance aluminum alloy parts can be prepared with high efficiency and low cost. The isothermal die forging technology has the advantages that the operation is easy, the production efficiency is high, the product quality is high and the practicability is high, thereby being suitable for industrialized use and popularization.

The invention discloses a preparation method of a nano zirconium oxide and chromium oxide composite material. The preparation method comprises the following steps: performing ball-milling dispersion to form uniformly dispersed slurry by taking 82-97wt% of pigment-grade chromium oxide micro powder as a matrix, 1-15wt% of nano zirconium oxide as a complexing agent and 3wt% of titanium dioxide micro powder as a sintering aid; and drying the slurry into powder, and then performing bonding forming to finally prepare the nano zirconium oxide and chromium oxide composite material. The nano zirconium oxide and chromium oxide composite material has a fine crystalline structure in which nano zirconium oxide is distributed among chromium oxide crystalline grains or wrapped in the chromium oxide crystalline grains, the volume density after sintering is 4.39-5.11g/cm<3>, and the porosity is 0.9-16.7%. By adopting the preparation method disclosed by the invention, the production of a composite material which has high strength, high compactness and good thermal impact resistance and can be stably operated in a furnace for a long time can be ensured.

A manufacturing technology of an arc-shaped molybdenum plate for a long-service-life heat shield specifically comprises the steps of preparing powder A which is of a rhenium-doped nanometer aluminum oxide structure, preparing nanometer lanthanum oxide, preparing the molybdenum plate, preparing a molybdenum blank through the molybdenum plate, and pressing the molybdenum blanket to obtain the targeted arc-shaped molybdenum plate. According to the manufacturing technology, the outward dispersing and oxidizing capacity of molybdenum is reduced through compound elements, so that the oxidizing resistance of molybdenum can be improved, and the service life can be prolonged by more than 30%; in addition, powder metallurgy and mechanical rolling are combined, so that the relative density of the manufactured arc-shaped molybdenum plate is high, and the plasticity is improved, and as a result, cracks can be avoided; an uniform fine grain structure is obtained, and thus physical performance and the mechanical performance can be improved.

The invention relates to a wear-resistant aluminum alloy and a preparation method thereof, and belongs to the technical field of non-ferrous metals. The aluminum alloy is prepared from the following chemical components in percentage by mass: 10.4 to 11.8 percent of Si, 1.5 to 2.5 percent of Zr, 1.2 to 2.2 percent of Ti, 0.05 to 0.1 percent of Cu, 1.2 to 1.7 percent of Sn, 0.5 to 0.7 percent of Mn, 1.4 to 2.4 percent of Nb, 0.07 to 0.2 percent of Fe, 0.03 to 0.15 percent of Ni, 0.05 to 0.15 percent of Cr, 0.14 to 0.22 percent of V, 0.2 to 0.25 percent of Mo and the balance of Al. The preparation method comprises the following steps: firstly, carrying out mechanical alloying through a high-energy ball mill, and then carrying out microwave sintering, low-temperature rolling, vacuum annealing treatment and magnetic field subzero treatment. By optimizing the contents of elements such as silicon, zirconium, copper, nickel and manganese and adding chromium, vanadium, molybdenum and tin, forced solid solution between atoms of different elements is realized by means of mechanical alloying, and a microwave sintering technology, a low-temperature rolling technology and a magnetic field cryogenic technology are applied to refine crystal grains, improve compactness and form deformation stress strengthening, so that the high-strength and high-toughness alloy is obtained. And the hardness and wear resistance of the aluminum alloy are improved.

The invention relates to a preparation method of a novel 7XXX aluminum alloy thin strip with high performance by jet casting, which comprises the following steps of: 1) smelting according to the following chemical components in percentage by weight: 4.8 to 6.3 percent of Zn, 1.6 to 2.5 percent of Mg, 1.6 to 2.5 percent of Cu, 0.1 to 0.15 percent of Zr and the balance of Al and other inevitable impurities; the single impurity content is less than or equal to 0.1%, and the total impurity content is less than or equal to 0.2 (2) nano-particle enhancement; 3) spray deposition and continuous casting; 4) cooling; 5) primary hot rolling; (6) cooling and secondary hot rolling; (7) coiling; and 8) post-processing. Compared with an existing 7XXX aluminum alloy, the 7XXX aluminum alloy thin strip cast and rolled through the spray deposition combined double-roller thin strip cast rolling technology has the advantages that the strength is improved by 25% or above, and the ductility is improved by 35% or above; compared with a steel plate, the weight is reduced by 50% or more.

The invention relates to a mobile phone rear cover material and a preparation method thereof. The mobile phone rear cover material is formed by compounding graphite micro-particles, potassium niobateand zirconium oxide, wherein the graphite microparticles can be uniformly dispersed in the potassium niobate composite zirconium oxide ceramic mobile phone rear cover material through a melting method, the KNbO3 synthesis raw materials are K2CO3 and Nb2O5, and bismuth oxide is added in the calcination process of the KNbO3 synthesis raw materials and a zirconium oxide raw material. The KNbO3 synthetic raw material and the zirconium oxide raw material are subjected to composite calcination, so that a uniform fine-grain structure is shown, and meanwhile, the KNbO3 synthetic raw material also hasthe characteristics of very high Curie temperature (about 420 DEG C), high frequency constant and the like. Due to no lead, the pollution to the environment can be reduced, and the volatilization of potassium and sodium in the sintering process can be avoided or reduced through hot-pressing sintering, so that a compact product is obtained. The preparation method disclosed by the invention is simple and convenient to operate and has an extremely wide application prospect.

The invention discloses a medical composite magnesium alloy and a preparation method thereof, the composite magnesium alloy comprises a bar and a sleeve which are nested together, the bar is made of an annealed Mg-Y-Zn alloy, the sleeve is made of an extruded Mg-Y-Zn alloy, and the bar and the sleeve form the composite magnesium alloy through a hot press molding process. The composite magnesium alloy has great directivity and flexibility of microstructure and macrostructure design. The preparation method is simple in process, magnesium alloy materials of different size series can be prepared in batches, and the requirements for different strength and degradation rates of different implantation parts in a human body and different periods after implantation can be met.

The invention relates to a jet cast rolling high-performance 7XXX aluminum alloy thin strip and a preparation method thereof, the aluminum alloy thin strip comprises the following components in percentage by mass: 4.8-6.3% of Zn, 1.6-2.5% of Mg, 1.6-2.5% of Cu, 0.1-0.15% of Zr, 0.01-0.08% of Ti, 0.001-0.008% of B, and the balance of Al and other inevitable impurities, the content of a single impurity is less than or equal to 0.1%, and the content of total impurities is less than or equal to 0.2%. Compared with an existing 7XXX aluminum alloy, the 7XXX aluminum alloy thin strip prepared through the spray deposition and double-roller thin strip cast rolling combined technology has the advantages that the strength is higher by 20% or above, and the ductility is higher by 30% or above; compared with a steel plate, the weight is reduced by more than 40%. The produced aluminum alloy thin strip can be widely applied to the field of aerospace, such as various aircraft fuselages, wing beams, cabin wallboards, aircraft high-stress structural parts, aircraft skins, high-strength structural parts in aircraft rockets and the like, and a wide space can be provided for aerospace high strengthening, light weight, energy consumption reduction and fuel economy improvement.

The invention discloses a molybdenum and molybdenum alloy material sintering method and application thereof.The molybdenum and molybdenum alloy material sintering method comprises the steps that after molybdenum and molybdenum alloy powder is pressed into a blank and put into a sintering furnace, hydrogen is introduced for heating sintering, the molybdenum and molybdenum alloy powder is subjected to passivating treatment before sintering, and the passivating treatment comprises the step that the molybdenum and molybdenum alloy powder is put into a ball mill for ball milling; the heating sintering comprises the following steps: heating for 2-3 hours, 2.5-3.5 hours and 6 hours, sequentially heating to 800 DEG C, 1100 DEG C and 1500 DEG C from room temperature, then heating to 1740 DEG C after 6-8 hours, and keeping the temperature for 6 hours; the passivating treatment comprises the steps that molybdenum grinding balls with the diameter of 5-20 mm and molybdenum and molybdenum alloy powder are put into a ball mill with the rotating speed larger than or equal to 30 rpm according to the ball-to-material ratio of (1-1.5): 1 to be subjected to ball milling, and the total ball milling time is 8-15 h. According to the sintering method, the highest sintering temperature is reduced, the total sintering time is shortened, the overall working efficiency is improved, and meanwhile it is guaranteed that a sintered product or billet has a microscopic structure with the average grain size being 15-20 microns.