13results about How to "Avoid coarsening" patented technology

The invention discloses a rare earth aluminum alloy cable material and a preparation method and application thereof, and relates to the technical field of aluminum alloy material preparation. The rare earth aluminum alloy cable material is prepared from the following raw material components in percentage by mass: 0.3 to 0.6 percent of Ce, 0.3 to 0.6 percent of Sc, 0.05 to 0.15 percent of Y, 0.10 to 0.20 percent of Fe, 0.05 to 0.15 percent of Si and the balance of Al. The preparation process comprises the steps of melting, refining, casting, homogenizing treatment, hot rolling, drawing and aging treatment. The rare earth elements Ce, Sc and Y are added, a specific heat treatment process and a processing process are combined, and the three rare earth elements Ce, Sc and Y have a synergistic effect, so that the performance and the electric conductivity of the cable material are balanced, and the cable material has good electric conductivity and elongation on the premise of ensuring certain tensile strength, and can meet the requirements of the cable industry.

This invention discloses a free-machining high-strength aluminum-lithium alloy, its preparation method, and its applications, belonging to the field of alloy materials technology. The free-machining high-strength aluminum-lithium alloy has the following weight percentages of elements: Li: 3.5–5.5%, Cu: 2.6–3.1%, Zn: 6.8–7.1%, Mg: 2.1–3.0%, Y: 1.5–4.0%, Bi: 0.85–1.05%, In: 0.05–0.08%, Cr: 0.05–0.45%, Ti: 0.02–0.04%, with the balance being Al. This invention involves batching, smelting, refining, online refining, online degassing and filtration, casting, homogenization, extrusion, and two-stage aging treatment to finally obtain a free-machining high-strength aluminum-lithium alloy with a uniform microstructure. This invention has a reasonable component ratio, low manufacturing cost, and the resulting product has excellent strength and hardness, and exhibits excellent surface finish after dry machining.

This invention belongs to the field of high-content ceramic / metal composite material preparation technology, specifically relating to a high-fatigue-strength B4C / Al composite material and its preparation method. This invention employs chemical vapor deposition to generate CNTs in situ on the surface of micro / nano-scale B4C particles. These CNTs are then thoroughly mixed with aluminum alloy powder, and a billet is prepared using SPS plasma discharge sintering equipment. After grinding and polishing, the billet is processed using a high-frequency current rolling test bench to obtain a high-fatigue-strength B4C / Al composite material. This invention aims to improve the interfacial bonding quality of ceramic / metal composite materials and inhibit harmful reaction products through the modification effect of CNTs; the addition of high-frequency current-assisted rolling enhances the fatigue resistance of the composite material, resulting in a B4C / Al composite material with excellent comprehensive performance.

This invention discloses a high specific surface area mesoporous tin oxide powder and its preparation method. The method includes: dissolving a tin source in a mixed solvent of alcohol and deionized water, adding a ketone complexing agent and a nonionic dispersant, and stirring to form a tin-based complex precursor solution; then transferring the solution to a hydrothermal reactor for hydrothermal aging treatment, causing the precursor solution to hydrolyze and condense, forming gel particles in situ; after solid-liquid separation, washing with alternating anhydrous ethanol and dilute ammonia water, and drying to obtain the precursor powder; finally, performing staged heating calcination under an air-nitrogen mixed atmosphere, first removing organic components at low temperature, and then completing the crystal phase transformation at high temperature to obtain rutile phase SnO2 powder. The powder has an average particle size of 8–15 nm and a specific surface area of ​​85–110 m² / g. 2 The powder has a pergola size of 3–6 nm and good dispersibility. This invention effectively suppresses grain agglomeration through complexation regulation, hydrothermal-sol-gel coupling, and gradient atmosphere calcination. The prepared powder is suitable for applications such as gas sensors, lithium-ion battery anodes, or transparent conductive films.

The invention belongs to the technical field of high-temperature alloy preparation, and relates to an oversized fine grain N06625 alloy plate and a rolling method and application thereof. The rolling method comprises the following steps: step 1, selecting a rolling blank with a specific specification; 2, the rolled blank is pretreated, and it is guaranteed that the surface of the rolled blank is free of cracks; 3, heating the rolled blank by using a heating furnace, and preserving heat; and 4, after heat preservation is finished, the alloy plate is discharged out of the furnace and subjected to large-deformation rolling, and the target N06625 alloy plate is obtained. The technical problems that a uniform structure and a fine grain structure are difficult to form in a traditional thermal forming process, and the risk of crystal mixing exists are solved; in addition, due to the fact that N06625 is difficult to form and a hot working window is narrow, N06625 can be formed into an oversized specification at a time through the method, the structure is uniform, and the grain size is larger than or equal to grade 8.

The application discloses a kind of reinforced toughened panel concrete and preparation method thereof, belong to panel concrete preparation technical field.The reinforced toughened panel concrete of the application includes the following components: low-heat portland cement, fly ash, slag powder, silica fume, fly ash microbeads, sand, water, copper-plated steel fiber, polyethylene fiber, high-performance water reducing agent, hydration temperature rise inhibitor and calcium-magnesium composite expansive agent.The reinforced toughened panel concrete of the application can realize the whole process performance optimization of panel concrete from micro defect inhibition to macro toughening and crack control, significantly improve the compressive strength and axial tensile strength and crack resistance of panel concrete, effectively solve the intrinsic brittleness and early shrinkage cracking risk of ultra-high strength concrete.

This invention discloses a high-strength, high-ductility, low-density steel and its preparation method. The composition is: C: 0.85–1.15%, Mn: 9.5–12%, Al: 8.5–11.5%, Ni: 2.5–3.5%, Cr: 2–3%, V: 0.3–0.5%, S≤0.005%, P≤0.008%, iron, and unavoidable impurities. The preparation method includes smelting, casting, forging, hot rolling, cold rolling, and recrystallization annealing processes. Through a high-C, medium-Mn, and high-Al synergistic design, Cr suppresses grain boundary carbide segregation, Ni promotes the formation of the B2 ordered phase, and V microalloying promotes the precipitation of the VC precipitate, forming a multi-scale layered structure composed of banded δ-ferrite, equiaxed (Fe,Ni)Al-type B2 phase, austenite, and nano-VC precipitates. The recrystallization annealing process achieves multi-scale layered structure control and synergistic strengthening of equiaxed (Fe,Ni)Al-type B2 phase and VC nanoprecipitates through rapid heating-short holding-rapid cooling. This invention breaks through the bottleneck of balancing strength, plasticity, and density in low-density steel, providing a high-performance material solution for automotive lightweighting.

This invention belongs to the field of alloy forming technology and discloses a 2GPa-grade hydrogen embrittlement-resistant hot-formed steel containing NbVTiMo composite precipitates, its preparation method, and its applications. Through the synergistic proportioning of Nb, V, Ti, and Mo quaternary microalloys, a NbVTiMo composite nano-precipitate with high thermal stability and good interfacial bonding is formed. Compared with traditional single / low-element microalloy precipitates, this composite precipitate can act as a highly efficient hydrogen trap, significantly improving the hydrogen atom capture ability, effectively inhibiting hydrogen enrichment at grain boundaries and defects, improving the hydrogen embrittlement resistance of hot-formed steel, and reducing the risk of hydrogen-induced cracking and delayed fracture. Simultaneously, extending the coiling holding time promotes the full nucleation and dispersed distribution of the precipitates; shortening the austenitizing holding time avoids excessive dissolution and coarsening of the precipitates, maintaining the nanoscale of the precipitates, and achieving a fine and dense distribution of the precipitates, thus balancing hydrogen embrittlement resistance with the strength and toughness of the steel.

The utility model discloses a hollow ball screw quenching device belongs to ball screw processing technical field, including the feeding platform, the one side fixed mounting of feeding platform has the cooling platform, the one side fixed mounting of cooling platform has the sectional quenching box, the inside of feeding platform is provided with the sliding slot, the inside fixed mounting of sliding slot has the sliding board, in the utility model, through setting telescopic cover and fixed clamp, through the moving program of control box setting, will the feeding tray move to first heating chamber, after heating, through controlling the feeding tray to move to second heating chamber and heat finally, after heating, through controlling the feeding tray to move to the one side of sectional quenching box, control fixed clamp to the hollow ball screw after heating and take the inside of cooling groove and move, through a plurality of cooling spray pipe and carry out hollow ball screw cooling, and quenching process makes hollow ball screw in lightweight, high accuracy, long life etc. Contradictory demand obtains the best balance.

This application relates to a wire rod, an arc-sprayed wire, and a preparation method thereof, belonging to the technical field of arc-sprayed materials. The chemical composition of the wire rod, by mass fraction, is: C: 0.08%~0.14%, Si: 0.10%~0.60%, Mn: 1.50%~2.00%, P≤0.020%, S≤0.020%, Cr≤0.10%, Ni≤0.10%, Mo≤0.05%, Cu≤0.10%, Ti≤0.010%, Al≤0.020%, N≤0.010%, TO≤0.010%, with the remainder being Fe and unavoidable impurities. The wire is prepared by optimizing the chemical composition of the alloy wire rod through processes such as smelting, continuous casting, rolling, surface treatment, rough drawing, copper plating, and fine drawing. The mass fraction of Cu is 0.10%~0.25%, and the other elements are the same as those in the wire rod. This wire material has excellent wear and corrosion resistance and adhesion strength to the aluminum alloy substrate. It can form a stable protective coating on the inner wall of the engine cylinder, taking into account both the advantages of engine lightweighting and high performance requirements, and effectively supporting long-term service.

The invention discloses non-oxidation drawing forming equipment for high-purity aluminum wires, which comprises a support frame, a sealing box fixedly connected to the top end of the support frame, a box door hinged to the side end of the sealing box, a driving part arranged on the sealing box and used for driving the aluminum wires to move along the radial direction of the aluminum wires, and a forming part arranged on the sealing box and used for drawing and forming the aluminum wires, the sealing box is provided with an annealing piece used for conducting annealing treatment on the aluminum wire after the aluminum wire is drawn and formed. Rapid heating, high heating efficiency and low energy consumption of the aluminum wire are achieved through the annealing piece by adopting the electromagnetic induction principle, the low-temperature high-purity argon annular spraying quenching of the spray gun can rapidly lock the microstructure of the aluminum wire, grain coarsening is prevented, the partition plate separates the induction heating area and the quenching area, mutual interference of heat is avoided, the stable annealing effect is guaranteed, and the service life of the aluminum wire is prolonged. And meanwhile, a micro-positive pressure environment is established through the air flow difference between the exhaust groove and the spray gun, air permeation is thoroughly blocked, argon recovery and purification are combined, it is guaranteed that the aluminum wires are not oxidized in the whole process, and the argon use cost is reduced.

This invention discloses an Al-Bi-Sn immiscible alloy and its rotational deposition solid-state additive manufacturing method, belonging to the fields of metal composite materials and solid-state additive manufacturing technology. In this invention, the Al-Bi-Sn immiscible alloy is, by atomic percentage (at.%), Al 100‑x‑ y Bi x Sn y The alloy is prepared by rotational deposition solid-phase additive manufacturing method, where x = 8~15, y = 7~20, and x+y = 15~35. By controlling the component ratio and microstructure, the present invention achieves uniform composite of BiSn solid solution matrix and Al phase particles, with no particle agglomeration, high density, and excellent hardness and self-lubricating wear resistance, which can directly meet the application requirements of lightweight wear-resistant components such as automotive bearings and dry friction bearings.

The invention discloses a preparation method of silver-plated copper powder based on high-activity replacement, and belongs to the technical field of metal surface treatment. The copper powder is subjected to alkali washing, acid washing and water washing and then subjected to ultrasonic treatment for 15-25 min at the temperature of 60-70 DEG C with a 35-45 vol% ethanol water solution. The surface activated copper powder is dispersed in a solution containing 10-30 g / L of a complexing main agent and 8-15 g / L of a complexing auxiliary agent, EDTA disodium is preferably selected as the complexing main agent, and potassium sodium tartrate is preferably selected as the complexing auxiliary agent. A silver-ammonia solution with the Ag < + > concentration being 8-12 g / L and the ammonia water concentration being 2.5-4.0 mol / L is dropwise added into a reaction system at the temperature of 35-45 DEG C at the speed of 0.2-1.0 mL / min; and after the reaction is finished, centrifugally washing the silver-plated copper powder, and drying in vacuum. According to the method, ethanol mixed liquid is used for heating ultrasonic treatment of copper powder, and active site density is improved. A double-complexing slow-release system is used for controlling the reaction rate, a complexing main agent is used for preventing particle aggregation caused by rapid reduction, and a complexing auxiliary agent is used for cooperatively regulating and controlling the Ag < + > release rate, so that a silver layer uniformly grows. And dropwise adding a silver-ammonia solution in a low-temperature gradient manner to realize gradual reduction of Ag < + >. The silver content of the prepared silver-plated copper powder is 20-25%, and the silver layer coverage rate is larger than or equal to 96%.