21results about How to "Uniform grain structure" patented technology

The invention discloses a high-performance special ceramic material and a preparation process thereof, and the preparation process comprises the following steps: proportioning tungsten carbide, ternary boride, titanium nitride, molybdenum, nickel, silicon, cobalt and other raw materials with nano silicon carbide whiskers according to a ratio, carrying out ball milling treatment, adding a forming agent, and continuing ball milling and granulation; and then, carrying out compression molding on the ceramic powder, carrying out liquid phase sintering in a CO atmosphere, and cooling to room temperature to obtain the high-performance special ceramic material. The Mo3NiB3 ternary boride is introduced, so that the hardness and impact resistance of the ceramic material can be improved, the interface bonding force between a ceramic matrix and a reinforcing phase is enhanced, and the bending strength is improved; the nano silicon carbide whiskers are subjected to nickel plating treatment, so that the interface bonding force can be improved, microcracks are reduced, and the strength and toughness of the ceramic material are enhanced; by optimizing the sintering process and adopting a staged heating mode, grain growth can be controlled, and the density and mechanical properties of the ceramic material are effectively improved.

The invention relates to the technical field of alloys, in particular to a Ni3Al-based alloy, a test bar, a turbine disc and a preparation method of the Ni3Al-based alloy. The invention discloses a Ni3Al-based alloy which comprises the following components in percentage by mass: 7%-9% of Al, 7%-8.5% of Cr, 0.13%-0.24% of C, 0.5%-2% of Ti, 3%-6% of Mo, 1%-3% of W, 1%-2% of Hf, 0.005%-0.03% of B and the balance of Ni. According to the Ni3Al-based alloy disclosed by the invention, all the elements are coordinated and matched, so that the Ni3Al-based alloy has a long-range ordered crystal structure, a stable high-temperature phase structure and excellent oxidation resistance, mechanical property and high-temperature property.

The invention discloses steel with excellent surface quality for a power battery shell and a manufacturing method thereof. The steel for the power battery shell comprises the following chemical components in percentage by weight: 0.015%-0.025% of C, less than or equal to 0.030% of Si, 0.10%-0.20% of Mn, less than or equal to 0.01% and less than or equal to 0.02% of P, less than or equal to 0.012% of S, 0.03%-0.08% of Cr, 0.02%-0.05% of Alt, 0.002%-0.005% of B and the balance of Fe and inevitable impurities. The cold-rolled sheet for the low-carbon deep-drawing battery shell is produced mainly by accurately controlling components in steel and through the working procedures of hot rolling, layer cooling, acid rolling, annealing and leveling. According to the cold-rolled steel plate produced by the method, the yield strength is 190-260 MPa, the tensile strength is 320-390 MPa, the ductility is larger than or equal to 38%, the HR30T range is 45-50, and the cold-rolled steel plate has the high-speed stamping capacity, certain anti-pressure capacity and excellent surface quality.

The invention belongs to but is not limited to the technical field of nickel-based alloy additive manufacturing, and discloses a heat treatment method and system for reinforcing and toughening an additive-formed heterogeneous nickel-based alloy, and the chemical components of the additive-manufactured nickel-based alloy are qualitatively and quantitatively analyzed by utilizing EPMA; carrying out homogenization heat treatment design by utilizing Thermo-Calc software; based on the obtained heat treatment temperature and dendritic crystal spacing, a linear curve of distribution of elements along with time diffusion is obtained, and the optimal temperature and time of homogenization heat treatment of the nickel-based alloy are obtained; and respectively calculating TTT phase diagrams corresponding to dendritic crystal nuclei and interdendritic crystal regions by utilizing a TTT phase diagram module in JMatPro software, and obtaining the optimal temperature and time of the stress relief heat treatment of the nickel-based alloy based on the characteristics of the precipitated phase of the nickel-based alloy. According to the method, a uniform grain structure is obtained after the material is rapidly cooled, the residual stress level in a component is reduced, and the strength and toughness of the material are improved.

The invention discloses a self-adaptive control system and method for neodymium-iron-boron sheet production, and relates to the technical field of material preparation and processing.The self-adaptive control system comprises a smelting analysis module, a rotating speed analysis module, an iron-boron alloy powder particle analysis module, a sintering temperature and duration analysis module, a neodymium-iron-boron sheet quality analysis module and a database; according to the method, various historical customer orders are combined, the appropriate smelting temperature and duration of the customer orders and the viscosity of neodymium iron boron alloy liquid based on the customer orders are obtained through analysis, the rotating speed of a melt-spinning machine is analyzed, parameters such as pressing pressure, sintering temperature and duration are determined according to the granularity of neodymium iron boron alloy powder, and finally the quality of the neodymium iron boron sheet is analyzed. And due to high intelligence and automation, the production efficiency is greatly improved, and the quality and consistency of products are ensured.

The invention relates to the technical field of bolt production, and particularly discloses a high-strength bolt machining process and device. Comprising the following steps: S1, material selection: selecting an alloy steel blank containing C, Si, Mn, Cr, Mo, V and the balance of Fe; s2, cold heading forming is conducted, specifically, the alloy steel blank is placed in a multi-station cold heading machine, and a bolt blank is formed through continuous cold heading and forging; s3, heat treatment is conducted, specifically, the bolt blank is subjected to quenching treatment and then subjected to tempering treatment, and a bolt base body is obtained; and S4, surface treatment is conducted, specifically, phosphating treatment is conducted on the surface of the bolt base body in sequence to form a phosphating layer, the composite coating is coated, and the high-strength bolt is obtained. The high-strength bolt machining process can be used for manufacturing connecting components requiring high reliability under complex working conditions such as heavy load, vibration and impact, and the high-strength bolt machining process has the advantages that the toughness, fatigue resistance and delayed fracture resistance are improved while high strength is kept.

The invention provides a cyanide-free electrolyte for hard gold electroforming and a preparation process of the cyanide-free electrolyte, and belongs to the technical field of gold plating processes. The preparation process comprises the following steps: adding 4-dimethylaminopyridine for reaction to prepare an additive A; adding lithium tert-butoxide for reaction to prepare an additive B; preparing an AuCl3 solution; 5, 5-dimethyl hydantoin is dissolved, and all the components are added. The preparation method comprises the following steps: stirring and mixing N-acetyl-L-cysteine, triphenyl methanol and dichloromethane, mixing trifluoroacetic acid, performing reduced pressure distillation, purification and elution, then adding triethylamine, 4-dimethylaminopyridine and acetic anhydride for reaction, and adding trifluoroacetic acid and triethyl silane for reaction to prepare an additive A; after being added into a cyanide-free electrolyte, in the process of electroplating a gold layer, the gold plating solution can effectively promote the formation of crystal nucleuses, prevent the overgrowth of crystal grains and promote the refinement of gold crystal grains, and the fine and uniformly distributed crystal grain structure can remarkably improve the hardness and wear resistance of the plating layer.

The application relates to the technical field of crystallizers, and discloses a manufacturing process of an ultra-large-specification crystallizer copper pipe, a semi-continuous casting machine set, an oil press machine set, an extruding machine set, a curve type box type heating furnace set and a high-precision Fanuc gantry five-axis machining center set, which are used for continuously casting the copper pipe group, extruding the copper pipe group, twice extruding the copper pipe group, heating and cooling the copper pipe group and machining the copper pipe group. The manufacturing process of the ultra-large-specification crystallizer copper pipe reduces the problems such as shrinkage and shrinkage hole of the copper pipe group, rapidly reversely extrudes the copper pipe group, ensures that the copper pipe group is free of cracks, the grain structure is uniform, the surface hardness is high, residual internal stress is eliminated during the copper pipe group machining process, the machining precision is improved, the electroplating precision and capacity of the copper pipe group through the ultra-large automatic electroplating tank are improved, the electroplating requirements of the copper pipe group are ensured, thus avoiding the influence of bubbles on the electroplating effect of the copper pipe group and improving the finished product quality of the copper pipe group.

The invention discloses a method for refining 316L stainless steel grains based on a selective laser melting technology, and belongs to the technical field of metal material additive manufacturing. According to the method, Fe-C-B alloy powder is added, a Fe-B or Fe-B-Cr type compound is formed to serve as a heterogeneous nucleation core when the 316L stainless steel component is manufactured through selective laser melting, columnar crystal epitaxial growth is inhibited, and grain refinement is achieved. By means of the synergistic effect formed by Fe, C and B, the negative influence of the SLM technology on the 316L stainless steel forming process is avoided, the advantages of the SLM technology are fully exerted in the 316L stainless steel component forming process, accordingly, the 316L stainless steel component high in compactness and excellent in comprehensive performance can be formed only through SLM, the method is stable in process, low in crack sensitivity and high in yield, and the production cost is reduced. The method has remarkable advantages in the field of additive manufacturing of high-performance 316L stainless steel components.

The invention discloses an aero-engine deep-cylinder thin-wall part forming process and a forming tool, and belongs to the technical field of high-temperature alloy annular part forging. The aero-engine deep-cylinder thin-wall part forming process comprises the following steps that 1, a blank is placed in a heating furnace to be heated to the initial forging temperature of the material; 2, upsetting, square drawing-out, rounding, upsetting, punching and chambering are carried out on the blank on a forging hammer; 3, performing rough turning on the blank; and 4, the blank is remelted and heated. And 5, the remelted and heated blank is subjected to chambering on a forging hammer, and the GH4169 bearing cylinder forged piece is obtained. And 6, the forge piece is subjected to solid solution heat treatment. And 7, sampling the forge piece subjected to solid solution, and carrying out physical and chemical test. And 8, roughly turning the forged piece qualified in the physical and chemical test. And 9, carrying out ultrasonic inspection on the forged piece subjected to rough turning. Aiming at the GH4169 deep-cylinder thin-wall part, the upper limit of the forming weight of the GH4169 deep-cylinder thin-wall part can be improved by optimizing the forming process, meanwhile, the forging deformation is uniform through the steps of upsetting, square drawing-out, rolling and upsetting, and the uniformity of the grain structure of the forging is effectively ensured.

The invention discloses a NO8810 series alloy forging method. The technical scheme comprises the following steps: step S1, preparing a steel ingot: firstly, preparing a metal raw material according to a design formula to prepare a formed steel ingot; step S2: sending the steel ingot into a trolley furnace for heating, comprising: a preheating stage: heating the steel ingot to 600 DEG C and keeping the temperature; a heating stage: heating the steel ingot to 910-940 DEG C and keeping the temperature, and then heating the steel ingot to 1180±15 DEG C; step S3: forging the steel ingot, wherein the opening forging temperature of the steel ingot is greater than 1000 DEG C, the final forging temperature is not less than 850 DEG C, the edges are chamfered, the edges are pulled out, the bottom is chopped and the riser is chopped, and then the steel ingot is returned to the furnace for keeping the temperature; step S4: secondary forging of the steel ingot into a material. The invention has the advantages that, by designing alloy elements and matching a suitable process, the precipitation of titanium nitride, carbide and carbonitride is reduced, thereby reducing the generation of γ' phase, refining the alloy structure and strengthening the mechanical properties of the alloy.

The invention discloses preparation of a high-strength, high-toughness and high-elongation TZM thick plate, and relates to the technical field of alloy preparation. The method comprises the steps that preparation raw materials are obtained, and the preparation raw materials comprise Mo powder, TiH2 powder, ZrH2 powder and C powder; the preparation method comprises the following steps: crushing and grinding TiH2 powder and ZrH2 powder, and sieving to obtain sieved TiH2 powder and sieved ZrH2 powder; the TZM powder is weighed according to the chemical component proportion and mixed, 0.5% of the sieved TiH2 powder is added in batches in the mixing process, and mixed powder is obtained; performing compression molding on the mixed powder to obtain a TZM powder blank; carrying out hot pressing sintering on the TZM powder blank to obtain a TZM blank; and the TZM blank is rolled and annealed to obtain the TZM thick plate. According to the embodiment of the invention, the high-strength and high-toughness TZM thick plate is prepared through the preparation steps of staged hot pressed sintering and star-shaped rolling, and the high elongation of the TZM thick plate is realized by optimizing the preparation and rolling annealing processes of the mixed powder.

The invention relates to a heating and heat preservation method for a martensite heat-resistant stainless steel forge piece, and belongs to the technical field of alloy forge piece machining. The heating and heat preservation method comprises the steps that whether a steel ingot needs to be preheated or not is judged according to the ingot passing temperature of the martensite heat-resistant stainless steel ingot; when the steel ingot needs to be preheated, low-temperature section heating and heat preservation are conducted on the steel ingot; the steel ingot is subjected to homogenizing heating and heat preservation treatment; forging the steel ingot, and obtaining a forge piece through an upsetting and drawing process; wherein in the upsetting and drawing process of the steel ingot, the steel ingot is subjected to long-time heat preservation treatment. The preheating and homogenizing heating processes before forging are added, firstly, whether the steel ingot is preheated before forging is determined according to the ingot passing temperature of the steel ingot, and the risk that a forge piece cracks due to the fact that the temperature of a cold ingot directly rises to the high temperature can be avoided; and secondly, the steel ingot is subjected to homogenizing heating and heat preservation treatment, meanwhile, long-time heat preservation in the upsetting and drawing process is matched, dendritic segregation can be improved, and the forge piece cracking tendency in the forging period is reduced.

The invention belongs to the technical field of electrical materials, and discloses a process method for improving the pressure resistance of a copper-chromium contact prepared from a vacuum casting base material, which comprises the following steps: preparing a copper-chromium contact part and carrying out a pressure resistance test, recording a pressure resistance result, carrying out solid solution and aging treatment on the copper-chromium contact part, and obtaining the pressure resistance of the copper-chromium contact part. The copper-chromium contact part subjected to solid solution and aging treatment is subjected to accurate grinding treatment, the surface of the copper-chromium contact part subjected to ultrasonic treatment is covered with industrial alcohol, ultrasonic treatment is carried out, the copper-chromium contact part subjected to ultrasonic treatment is put into a temperature constant-temperature box to be dried, then a voltage withstanding test is carried out, and a voltage withstanding test result is recorded. Through solid solution aging, accurate grinding, ultrasonic treatment and drying treatment, the internal grain structure of the copper-chromium contact is homogenized, the surface roughness of the contact is obviously reduced, the surface quality of the contact is improved, the voltage withstanding level of a part is improved, the surface roughness is kept to be smaller than or equal to Ra2, and therefore the breakdown voltage of the part is improved.

The present application relates to a laser cladding repair process for fatigue cracks on gear tooth surfaces. A control system is used to detect the shape of the fatigue crack in real time. Different laser processing parameters are used for the straight segments and curved segments of the fatigue crack. In particular, a single laser beam is replaced with two laser beams for the curved segments of the fatigue crack, thereby effectively ensuring the welding quality of the entire fatigue crack. The fatigue crack welding efficiency is high, and the grain structure of the cladding area is uniform, thereby effectively improving the overall repair quality of the fatigue crack.

The invention relates to a high-performance alloy bump material and an IC packaging technology, and the technology comprises the following steps: employing a metallographic microscope to detect the internal crystal grain structure of an alloy bump, and dividing the alloy bump into at least eight heating regions; according to detection and region division results, working parameters of the electromagnetic induction heating device are dynamically adjusted, and accurate control over the alloy bump heating process is achieved; and a metallographic microscope and a four-probe tester are used for detecting the structure and resistivity of the heated crystal grains, so that the product quality is ensured. The process has the characteristics of subdivision of a heating area, dynamic adjustment of parameters, realization of uniform heating, improvement of heating efficiency, energy conservation and emission reduction; and meanwhile, the product reliability is improved.

The invention discloses a recycled aluminum grain refinement process and a recycled aluminum processing device, and specifically relates to the technical field of recycled aluminum processing, including a crusher for crushing waste aluminum products, a cleaning cylinder for dust removal of waste aluminum products, a cutting and screening machine, a furnace for melting waste aluminum products, and a temporary storage furnace for placing aluminum liquid. Through the provision of the cleaning cylinder, dust particles attached to the surface of the aluminum products can be effectively cleaned off. After removing surface impurities, the recycled aluminum can be refined more smoothly during the melting and cooling process, which is helpful to obtain a more uniform and finer grain structure. Through the provision of the cutting and screening machine, fragments of different sizes can be more evenly distributed in the furnace, which increases the melting surface area and makes the melting process more efficient. Fragments with uniform specifications are more easily affected by the same heat during the melting process, which is conducive to the uniform growth of grains, thereby obtaining a more uniform grain structure.

The invention discloses a preparation method of a synergistically hardened and toughened WC-FeNiCo-CeO2 hard alloy material. The preparation method specifically comprises the following steps: (1) preparing W-CeO2 composite powder; (2) preparing an entropy alloy adhesive in FeNiCo; (3) preparation of WC-FeNiCo-CeO2 composite powder is carried out; and (4) spark plasma sintering. CeO2 is introduced through a wet chemical method to serve as a reinforcing phase, it is guaranteed that trace additives are evenly distributed in the whole composite powder, grain boundaries are purified, the wettability of the grain boundaries and a binding phase is improved, gaps are promoted to be filled with a liquid phase, and the porosity of the alloy is reduced; co is replaced by a FeNiCo medium-entropy alloy adhesive, so that the material cost is reduced, and the hardness and the fracture toughness are improved; the hard alloy composite material which is high in density, uniform in grain structure, excellent in mechanical property and wider in application range is prepared through spark plasma sintering.

The invention provides a loose tooling forging manufacturing method of a gas turbine disc, which comprises the following steps of: heating a cast ingot for upsetting and drawing to obtain a forged rod; the forging rod is heated to the pre-forging temperature, pre-forging is conducted in a pre-forging lower forming die, and pre-forging comprises the steps that overall downward pressing is conducted firstly, then centering downward pressing is conducted through a punch, and a pre-forged piece is obtained; carrying out homogenizing heat treatment on the pre-forged piece; and the pre-forged piece obtained after homogenizing heat treatment is heated to the finish forging temperature, finish forging is carried out in a finish forging lower forming die, the finish forging comprises the steps that centering pressing is carried out through a punch, then spinning is carried out through a square anvil, and the gas turbine disc piece is obtained. According to the loose tooling forging method of the gas turbine disc, net forming of the disc is directly achieved, grain structures are uniform, no deformation dead zone exists, production can be achieved through a 5000T hydraulic machine, the tonnage requirement of forging equipment is greatly reduced, material consumption is reduced, and the production cost is greatly reduced.

This invention provides a variable-temperature forging process for difficult-to-deform lightweight aluminum / magnesium alloys. The process involves determining the recrystallization temperature to lock in the preheating temperature; heating the difficult-to-deform aluminum or magnesium alloy billet to the preheating temperature; maintaining a die temperature 50-200°C higher than the billet temperature; implementing an initial temperature transfer deformation process on a forging press, with the die at a high temperature and the billet at a low temperature; ensuring the die temperature is 50-200°C higher than the billet temperature; performing plastic deformation at the same temperature for both the die and the billet when the forging deformation reaches 1 / 3-2 / 3 of the stage; maintaining pressure with the die temperature 50-100°C lower than the billet temperature; water quenching the formed forging, followed by aging heat treatment. This variable-temperature forging process for difficult-to-deform lightweight aluminum / magnesium alloys reduces the tendency for deformation damage during deformation, ensures low-temperature deformation of the workpiece without damage or cracking, improves the deformation uniformity of the workpiece, and optimizes its microstructure and mechanical properties.

The invention relates to a high-toughness wear-resistant hypereutectic Al-Mg2Si alloy and a preparation method thereof. The alloy comprises the following chemical components in percentage by mass: 4.77-6.70% of Si, 8.23-11.40% of Mg, 0.1-0.5% of Cu, less than or equal to 0.1% of Ti, 0.01-0.20% of P, Sr and Nd, and the balance of Al and inevitable impurities. The alloy is prepared through the process steps of fine grain strengthening treatment, casting, solution treatment, large-deformation rolling and the like, and the mechanical property of the alloy is remarkably improved by adopting the mode of combining asymmetrical rolling and synchronous rolling. The prepared aluminum alloy shows excellent performance in the aspects of yield strength, tensile strength and ductility, the yield strength can reach 180 MPa, the tensile strength can reach 220 MPa, and the total ductility is not lower than 4.0%. In addition, the grain structure of the alloy is uniform, Mg2Si particles are well distributed, and the wear resistance of the alloy is further improved. The alloy is suitable for the field of engineering materials requiring high strength, high toughness and excellent wear resistance.