8 results about "Equal channel angular extrusion" patented technology

A method for manufacturing an equiaxed crystal target material, comprising the following steps: a metal bar is made into a forged base material by a radial forging process; the forged base material is made into a first plate material by a rolling process and a plate forging process, the rolling process is rolling along the axial direction of the forged base material; a second plate material is obtained by reciprocating an equal channel angular extrusion process on the first plate material with an equal channel angular extrusion die, the cumulative average equivalent strain of the second plate material is greater than 10, wherein the feeding direction of the first plate material into each equal channel angular extrusion die is the same as the rolling direction of the forged base material; and an annealing and recrystallization heat treatment process is performed on the second plate material to obtain an equiaxed crystal target material. Through the above steps, an equiaxed crystal target material with a grain size of not greater than 20 μm can be obtained for use in the semiconductor industry.

The invention discloses a preparation method of a thermal bimetal strip, which specifically comprises the following steps: step 1, a copper strip or an aluminum bar sequentially penetrates through a sliding sleeve and a sleeve on a base, and then a liquid pump pumps a pickling solution and pure water in a liquid tank into an inner cavity through a liquid conveying pipe; the water flows into the sliding sleeve through the overflow hole to be in contact with the surface of the copper strip or the aluminum bar, so that the oxidation film on the surface of the copper strip or the aluminum bar is removed and rinsed; secondly, the cleaned copper strip or aluminum bar enters a sleeve, and through movement of an arc block and a sliding block, the technical field of metal composite materials is achieved, and the problem that when an existing copper-aluminum bimetal composite material is prepared, due to the fact that dense oxidation films exist on the surfaces of pure copper and aluminum materials, the pure copper and the aluminum materials are subjected to continuous equal-channel angular extrusion after coating is solved; and due to large differences of plasticity, hardness and deformation behaviors, cracking or stripping is easily generated at an interface, so that the forming quality and the mechanical property of the composite material are influenced.

The invention relates to the technical field of magnesium alloy large-size cast ingot preparation, in particular to a large-size rare earth magnesium alloy cast ingot hot crack defect synergistic inhibition method which comprises the following steps: S1, intermediate alloy pretreatment: placing an Mg-30Zr intermediate alloy blank in an equal-channel angular extrusion die, applying 70%-80% of deformation, and carrying out equal-channel angular extrusion on the Mg-30Zr intermediate alloy blank; the Zr clusters with the original size larger than or equal to 762 micrometers are crushed into discrete particles with the particle size ranging from 1 micrometer to 5 micrometers; s2, smelting and modification treatment: preparing materials according to a target alloy ZK61, and smelting industrial pure Mg and Zn and the Mg-30Zr intermediate alloy pretreated in the step S1 under a protective atmosphere; through electromagnetic oscillation and forced convection, the melt convection speed is increased, center melt heat dissipation is accelerated, temperature field / solute field homogenization is achieved, the structure component consistency is improved, casting stress generated in the solidification process is reduced, the generated axial circulation speed exceeds the rare earth sedimentation speed, and the bottom sedimentation phenomenon is effectively restrained; and the distribution uniformity and the yield of the rare earth are improved.

The invention discloses a reciprocating T-shaped variable channel angular extrusion semi-solid rheoforming aluminum alloy and an integrated forming method, and belongs to the technical field of metal material machining. According to the method, the semi-solid rheoforming technology and the reciprocating type T-shaped variable channel angular extrusion technology are integrated, and slurry preparation, structure modification and part forming are continuously completed in the same die system. The core of the die is that the die is provided with a T-shaped channel and three extrusion barrels which are communicated with the T-shaped channel and have larger sections, pressure is alternately applied through a punch, so that semi-solid slurry flows between the extrusion barrels and the channel in a reciprocating mode and is sequentially subjected to forward extrusion densification and equal-channel angular extrusion shearing refinement, grains are ultra-refined to be micron, and casting defects are eliminated. And finally, directly pressing and forming by replacing the cavity die. The method solves the problem that the structure and the shape of a traditional process are difficult to consider at the same time, achieves near-net-shape, high-efficiency and low-energy-consumption integrated manufacturing of high-performance complex parts, and is particularly suitable for production of high-performance aluminum alloy parts in the fields of aerospace, new energy automobiles and the like.

The invention provides a preparation method of an aluminum alloy and a product thereof. According to the method, the anti-fatigue performance of the aluminum alloy is improved by adjusting the process sequence of multidirectional forging and pressing; the yield strength is improved through stabilizing treatment and differential temperature equal channel angular pressing; the uniformity of the anodic oxidation appearance of the aluminum alloy is improved by adding Cr and Mn elements; the corrosion resistance of the aluminum alloy material is improved through the dispersed phase pre-precipitation step; by reducing the viscosity of a molten aluminum alloy liquid phase, the pore generation rate of an aluminum alloy material during pulse laser welding is reduced.

A method for manufacturing an equiaxed crystal target includes steps. A bar-shaped metal material is formed to a forged material by using a radial forging process. The forged material is formed to a first plate material by using a rolling process and a plate forging process, wherein the rolling process is to roll the forged material along an axial direction thereof. An equal channel angular extrusion mold is used to reciprocally perform an equal channel angular extrusion process on the first plate material to obtain a second plate material, wherein a cumulative average equivalent strain of the second plate material is greater than 10, and a feeding direction of the first plate material into the equal channel angular extrusion mold is the same as the axial direction of the forged material. A recrystallization annealing / heat treatment process is performed on the second plate material to obtain an equiaxed crystal target.

The invention discloses a corrosion-resistant spoke forming process which comprises the following steps: firstly, refining an austenitic stainless steel wire into an ultra-fine grain / nanocrystalline structure through equal-channel angular extrusion in combination with low-temperature rolling, and improving the grain boundary density; then, surface pollutants are sequentially removed by adopting pulse fiber laser, an amorphous / nanocrystalline mixed activation layer is formed, and the surface activity is enhanced; mixed reaction gas is introduced into a closed reaction chamber, a gradient composite permeation layer composed of a ceramic phase outer layer, a mixed middle layer and a Cr / Ni-rich inner layer is formed at the temperature of 450-650 DEG C, and metallurgical bonding with a base body is achieved; finally, a porous ceramic membrane is generated on the surface of the permeation layer, and an indicator sensitive to Cl <-> or pH is filled through vacuum impregnation, so that the corrosion early warning function is achieved. The gradient infiltrated layer binding force critical load of the spoke obtained through the method is larger than or equal to 80 N, the salt spray test corrosion resistance time is larger than or equal to 2000 hours, and the spoke has the self-repairing capacity and the rapid corrosion early warning response, is suitable for various scenes such as bicycles, automobiles and ocean engineering and has the remarkable industrial application value.

The application provides a method for reciprocating equal-channel-angle-pressing strengthening of magnesium-zinc alloy, and belongs to the technical field of alloys. In the reciprocating ECAP process, high-temperature strain is used to activate the pyramidal <c+a> dislocation slip, so that a stronger deformation capacity is obtained, and dynamic recrystallization is induced, so that the generation of cracks in the material in the ECAP process is avoided, and multiple passes can be implemented to obtain a more fine and uniform microstructure and higher strength and plasticity. Meanwhile, in the high-temperature strain process, the uniform dynamic segregation of precipitated phases occurs at the grain boundaries, the migration of the grain boundaries is inhibited, and the recrystallized grains are uniformly refined. By controlling the angle of the equal-channel-angle-pressing die and the extrusion passes, the magnesium-zinc alloy can have finer grains and more stable grain boundaries, so that the strength and plasticity of the magnesium-zinc alloy are simultaneously improved, and therefore the magnesium-zinc alloy has better comprehensive mechanical properties.