8results about How to "Uniform grain size" patented technology

The present application relates to a kind of ceramic materials for 5G medium filter and preparation method thereof.The chemical composition of the ceramic material for 5G medium filter is x CBZS glass-(1-x) Mg 0.95 Ca 0.05 Ti 0.95 (Zn 1 / 3 Nb 2 / 3 ) 0.05 O3, wherein wt%≤x≤wt%;The composition of the CBZS glass includes: 40-60 mol% CaO, 10-25 mol% B2O3, 25-45 mol% ZnO, 10-20 mol% SiO2.

This invention discloses a nanocrystalline alloy magnetic core and its preparation process. The invention relates to the field of magnetic materials technology and comprises the following components by weight percentage: 81%–85% pure iron, 0.8%–1.2% pure copper, 8%–10% ferrosilicon, and 5.5%–8.5% ferroboron. This nanocrystalline alloy magnetic core and its preparation process, by uniformly spirally winding copper sheets around the inner and outer sides of the magnetic core, can delay the heating of the inner and outer surfaces of the core, reduce the temperature difference between the center of the core and the inner and outer sides, and make the temperature distribution in the center and sides of the core more uniform. This promotes more uniform elimination of internal stress and facilitates simultaneous nucleation and growth at different locations of the core during the second annealing step, resulting in more uniform grain size at the inner and outer locations of the core, thereby improving the core performance.

The invention belongs to the technical field of non-ferrous metal processing, and relates to a fine-grain Nimonic90 high-temperature alloy bar and a forging method and application thereof. The cast ingot is prepared by adopting a duplex smelting process of vacuum induction smelting and vacuum consumable remelting, the content of inclusions and impurity elements of the cast ingot is low, the purity is high, micro segregation can be effectively controlled by a small ingot type, and an ideal blank is provided for obtaining a uniform and small forged structure for a subsequent bar after high-temperature homogenization; furthermore, finished product forging is utilized, and a uniform and fine forged structure is obtained; meanwhile, double-V-anvil deformation is adopted, and the residual stress level of the bar is greatly improved; after the heating number of finished product forging, stress relief annealing treatment is added, long-time heat preservation is conducted at the temperature slightly lower than the grain growth temperature, and residual stress existing in the bar is eliminated; and therefore, an ideal structure with the uniform forged grain size of 7-8 levels and the uniform grain size of 4-5 levels after high-temperature solid solution heat treatment of the high-temperature alloy bar is obtained.

The invention relates to the technical field of high-temperature alloy manufacturing, and discloses a GH4169 alloy small-specification bar and a preparation method thereof.The method comprises the steps that a GH4169 alloy cast ingot is subjected to two-stage homogenization treatment; performing forging cogging on the homogenized cast ingot by adopting a high-speed forging machine to obtain a rolled blank; and the rolled blank is fed into a continuous rolling unit to be rolled, and the GH4169 alloy small-specification bar is obtained. According to the method, the cast ingot is homogenized at high temperature for a long time, diffusion and migration of elements can be promoted, and the uniformity of internal components of the cast ingot is improved; the cast ingot is subjected to large-deformation forging cogging by a high-speed forging machine, and carbides and crystal grains can be obviously uniform and refined; and a continuous rolling unit is adopted for rolling into a material, so that uniform deformation can be further ensured, and uniform and fine grains and carbides are obtained.

This invention relates to the field of aluminum alloy extrusion technology, and particularly to a split extrusion process for thin-walled aluminum alloy 3003. The invention involves sequentially subjecting an ingot to integrated homogenization annealing and preheating, die heating, extrusion cylinder heating, and split extrusion treatment, resulting in a split extruded aluminum alloy 3003 thin-walled part. The chemical composition of the ingot (mass percentage) is as follows: Si: 0.05–0.1%, Fe: 0.3–0.4%, Cu: 0.05–0.1%, Mn: 1.05–1.1%, Mg: 0.008–0.01%, Zr: 0.004–0.005%, Cr: 0.004–0.005%, Ni: 0.004–0.005%, Zn: 0.008–0.01%, Ti: 0.02–0.025%, Ce: 0.04–0.05%, with individual impurities ≤0.025%, total impurities ≤0.15%, and the remainder being Al. This method can shorten the heating time of split extrusion of thin-walled aluminum alloy 3003 parts, improve production efficiency, and obtain higher dimensional accuracy and uniform grain size by controlling billet temperature, deformation temperature and deformation speed.

This invention discloses a high-performance wrought magnesium-lithium alloy, comprising the following components by mass percentage: Li 4.8%~5.3%, Zn 5.7%~6.2%, Y 1.8%~2.3%, with the balance being Mg. The alloy is prepared as follows: 1. Raw materials of each component are taken according to the mass percentage of the target magnesium-lithium alloy, and smelted and cast to obtain a magnesium-lithium alloy ingot; 2. The magnesium-lithium alloy ingot is subjected to homogenization heat treatment; 3. After low-temperature preheating, it is subjected to low-temperature extrusion and cooled to room temperature. The magnesium-lithium alloy of this invention, by adding Zn and Y elements, introduces a network W phase, MgZn phase, and MgY phase as reinforcing phases to strengthen the alloy. Combined with the homogenization heat treatment followed by low-temperature extrusion deformation in the preparation process, cold forming capability is increased, and the second phase is effectively broken up, synergistically improving the strength and plastic mechanical properties of the magnesium-lithium alloy, making it suitable for aerospace and other fields.

The invention provides a magnesium-aluminum composite oxide carrier and a preparation method thereof as well as a methane dry reforming catalyst and a preparation method and application thereof. The preparation method of the magnesium-aluminum composite oxide carrier comprises the following steps: dissolving magnesium salt in deionized water to form a magnesium salt solution; dissolving an aluminum source in an acid solution to form aluminum sol; mixing the magnesium salt solution and the aluminum sol, adjusting the pH value to 3-4 by using an acid solution, and continuously stirring to obtain a turbid liquid; in the turbid liquid, the molar ratio of aluminum to magnesium is (1: 1)-(3: 1); and drying and roasting the turbid liquid to obtain the magnesium-aluminum composite oxide carrier. The preparation method of the magnesium-aluminum composite oxide carrier is simple in process, environment-friendly and convenient for large-scale production, meanwhile, the obtained carrier has a relatively high specific surface area, and the dispersion degree of active metal nickel can be improved by preparing the supported nickel-based methane dry reforming catalyst by taking the magnesium-aluminum composite oxide as the carrier, so that the grain size of the active metal nickel is reduced, and the catalytic activity of the catalyst is improved. The high-temperature sintering resistance of the catalyst is improved; the activity stability is enhanced.

The application discloses a preparation method of a gadolinium-containing nickel-based alloy component. The gadolinium-containing nickel-based alloy pre-alloy powder is prepared into the gadolinium-containing nickel-based alloy component by using a hot isostatic pressing process with a temperature of 1080-1160 DEG C and a pressure of 120-200 MPPa, so that a Ni5Gd rare earth phase is refined to micron / submicron dispersion distribution, a matrix is an equiaxed crystal organization of complete recrystallization, original particle boundaries are completely eliminated, and grain sizes are uniformly distributed at about 5.3 mu m, thereby obtaining a near-net-shape product of the gadolinium-containing nickel-based alloy component. The application further discloses a gadolinium-containing nickel-based alloy component. Compared with the prior art, the application realizes the synergistic optimization of a rare earth phase and a matrix organization in the same process: the Ni5Gd rare earth phase is inhibited from coarsening, meanwhile, the matrix is completely recrystallized and the original particle boundaries are eliminated, and a near-net-shape gadolinium-containing nickel-based high-temperature alloy component with highly uniform organization and excellent strength-plasticity matching is obtained at one time.