17 results about "Martensite transformation" patented technology

This invention discloses a high-elongation aluminum alloy for lightweight automotive components and its preparation method, relating to the field of aluminum alloy material technology. It features a hierarchical porous structure with surface micron-sized closed pores and a core nano-sized through-pore. The Ti and Mn elements synergistically form an Al-Ti-Mn martensitic phase transformation core region with Al, and the Cr element precisely controls the martensitic phase transformation initiation temperature to room temperature, ensuring stable triggering of the austenite-to-martensitic phase transformation and energy absorption during room-temperature collisions. This invention achieves initial impact buffering and gradual collapse energy absorption through a hierarchical porous structure with surface micron-sized closed pores and a core nano-sized through-pore. This dual energy absorption mechanism significantly improves the material's strength-ductility product, far exceeding that of traditional aluminum alloys.

The application discloses a high-pressure quick connector based on precipitation hardening stainless steel and a production process thereof, and belongs to the technical field of materials. In the production process, carbon-coated NbC-Cu functional carbide is added as an additive. The carbon-coated NbC-Cu functional carbide contains a nano copper phase. Through low-temperature solid solution and aging treatment, two kinds of precipitated phases can be generated. One is a B2-NiAl precipitated phase in high-coherent relation with the matrix, and the other is an FCC-Cu precipitated phase in incoherent relation with the matrix. The high-pressure quick connector can generate phase transformation induced plasticity caused by the martensite transformation of austenite in the deformation process, and the FCC-Cu precipitated phase can capture the hydrogen evolution as an effective hydrogen trap to reduce the diffusible hydrogen content in the matrix to the maximum extent, thereby reducing the hydrogen embrittlement sensitivity while ensuring the good mechanical properties of the high-pressure quick connector.

This application provides a high-entropy alloy-induced carbide precipitation-strengthened iron-based high-temperature wear-resistant coating and its preparation method, relating to the field of high-temperature wear-resistant coating technology. The method includes drying high-entropy alloy powder and iron-based alloy powder; mixing the dried powders; and then using laser cladding equipment to prepare the coating. The material used in this application achieves martensitic transformation strengthening and carbide synergistic strengthening by precisely controlling the precipitation of eutectic carborides during solidification using high-entropy alloys. During solidification, δ-Fe nucleates and grows first. As the liquid phase composition changes to near the eutectic point, Cr and Mo carborides (MC) begin to nucleate and grow. At this point, δ-Fe begins to transform into γ-Fe, which then undergoes a martensitic transformation. After cooling to approximately 700°C, the phase transformation nearly stops, and C only diffuses short-range to form M6(CB) type carborides, promoting the synergistic strengthening mechanism of the material and balancing strength and toughness.

This invention belongs to the field of metastable austenitic stainless steel preparation technology, and discloses a method for preparing metastable austenitic stainless steel with a controllable ultrafine / micron-grained bimodal heterostructure. The method includes: firstly, in M… s Point and M d Metastable austenitic stainless steel sheets are cold-rolled between points, with the deformation amount controlled at 10%-80%, to obtain rolled sheets with specific phase contents through deformation-induced martensitic phase transformation; subsequently, at a temperature higher than M... d The material is subjected to warm rolling deformation to 80% of the total deformation under conditions below the recrystallization temperature; finally, it is subjected to short-time annealing treatment at 700-750℃. This invention can achieve quantitative control of the ratio and size of micron and submicron crystals by adjusting the initial cold rolling deformation and subsequent annealing treatment, which solves the problems of high randomness in the preparation of heterogeneous structures and difficulty in preparing large sizes in the prior art. The resulting material has excellent strength and plasticity matching, and the process is efficient and easy to industrialize.

This application provides a high-strength Fe-Mn damping alloy and its preparation method. The high-strength Fe-Mn damping alloy comprises the following components by mass percentage: Mn: 15%–18%, with the balance being Fe and unavoidable impurities. When the Mn content is 15%–18%, the thermally activated α'-martensite transformation, which is detrimental to damping performance, can be completely suppressed, while the thermally activated ε-martensite phase transformation is sufficient, resulting in an alloy product with a dual-phase structure of austenite and ε-martensite. The damping alloy exhibits high strength and plasticity, and at a strength of 3.5 × 10⁻⁶... ‑4 It exhibits excellent damping performance under strain amplitude, meeting the performance requirements of high-damping materials. The high-strength Fe-Mn damping alloy of this application does not require the addition of other alloying elements, and its cost is far lower than that of traditional damping alloys such as Mn-Cu, Zn-Al, and Mg-Ni.

The application discloses a high-vanadium-content V-Ti-Ni shape memory alloy and a preparation method thereof. The method is based on density functional theory simulation to screen the best composition of V-doped Ti-Ni alloy. Then, high-purity sponge titanium, nickel and self-made vanadium-nickel alloy are used as raw materials to smelt, hot forge, twice hot roll and cold draw in a vacuum induction furnace to obtain a high-vanadium-content V-Ti-Ni shape memory alloy wire with a wire diameter of Φ2-Φ3 mm. The hardness and elastic modulus of the final product, the high-vanadium-content V-Ti-Ni shape memory alloy wire, are equivalent to those of conventional Ti-Ni, and the martensitic phase transition temperature is significantly reduced, so that the reversible shape memory effect can be realized in an extremely low-temperature environment, and the high-vanadium-content V-Ti-Ni shape memory alloy wire is suitable for deep sea, deep space exploration and low-temperature micro-actuator manufacturing in a low-temperature environment. The preparation method can be directly applied to an existing Ti-Ni alloy production line without adding special equipment, and the process is economical and cost-effective.

The application relates to the field of metal materials, and discloses a steel for small-size steel balls for mine grinding and a preparation method of the small-size steel balls. The steel for the steel balls comprises the following components: C: 0.4%-0.9%, Mn: 3.0%-5.0%, Si: 1.4%-1.8%, Cr: 0.8%-1.3%, Ni: 0.3%-0.6%, Mo: 0.2%-0.4%, V: 0.15%-0.25%, Nb: 0.02%-0.06%, the rest is Fe and inevitable impurities, and the contents of Mn, V and Nb need to be controlled in coordination. The small-size steel balls are forged and hot-rolled, and are subjected to non-heat-insulation grading quenching and deep cryogenic treatment. The steel ball components and the preparation process realize low-temperature martensite transformation, obtain fine and uniform martensite structure, and the steel ball has high hardness, high impact toughness and excellent impact fatigue resistance.

This invention provides a continuous heat release device, seat cushion, and toilet seat cover based on solid spring-loaded material, belonging to the field of refrigeration and heating technology. It includes a solid spring-loaded material body, a pressure rod, a force-applying component, and an energy storage and buffering mechanism. The output end of the pressure rod abuts against the solid spring-loaded material body to compress it, causing deformation and heat release. The force-applying component has instantaneous movement along a first direction. The energy storage and buffering mechanism connects the output end of the force-applying component and the input end of the pressure rod, storing the mechanical energy of the force-applying component and driving the pressure rod to slowly and continuously compress the solid spring-loaded material body through potential energy. This invention ensures that the solid spring-loaded material body has sufficient time to undergo a complete and more thorough martensitic phase transformation, thereby maximizing the release of its latent heat, extending the effective heat release time, and thus improving the heating efficiency and heating stability of the device.

The present application belongs to the technical field of metal material heat treatment, and particularly relates to a process method for preparing a semi-ring type cast alloy steel part. Before smelting, the chemical component value is set, appropriate alloy elements are added in corresponding order, argon is passed through the whole refining process to strengthen stirring and accelerate the homogenization of components and temperature, and the molten steel meeting the requirements and being relatively uniform is obtained. Argon protection pouring is adopted to prevent the molten steel from being oxidized, and sufficient molten steel pouring allowance is left. The one-time high-temperature annealing and one-time high-temperature tempering pretreatment process is adopted to eliminate the non-equilibrium structure in the part, fine carbide particles and ferrite structure are obtained through recrystallization, and the structure inheritance is avoided. The part is heated to above the austenitizing temperature and kept for a sufficient time length, so that the part structure is completely austenitized, then the part is quenched through a faster cooling speed, so that the part temperature is below the Ms point to occur martensite transformation. The part is tempered at a suitable temperature to obtain a part with good comprehensive performance.

This invention proposes a polycrystalline Co-V-Ga-Si alloy, its preparation method, and its applications, belonging to the field of shape memory alloy solid-state refrigeration technology. The general chemical formula of the polycrystalline Co-V-Ga-Si alloy is Co. 50 V 35 Ga 15‑x Si x 0X1.5, where the subscript indicates atomic percentage content. The martensitic transformation temperature range of the alloy is 220-310 K, the fracture stress is greater than 1080 MPa, and it can produce an adiabatic temperature change greater than -5.1 K under 800 MPa stress. This invention improves the elastic-thermal properties of the Co-V-Ga alloy by introducing a certain amount of semiconductor Si element, and effectively reduces the critical stress driving the martensitic transformation and the stress hysteresis during the transformation process. This invention has the advantages of simple process flow, excellent hyperelastic properties, and large elastic-thermal temperature change of the alloy, and has broad application prospects in the field of solid-state refrigeration.

This invention relates to a stress monitoring and early warning system for suspension clamps in high-voltage power lines, belonging to the field of intelligent monitoring of high-voltage lines. The system consists of RFID sensing tags installed on the suspension clamps and an inspection RFID reader. The RFID sensing tag integrates a force-sensitive overload memory unit, a tag chip, and an antenna. Magnetostrictive alloy microwires within the unit are connected to the force transmission path. When the tensile force exceeds a threshold, an irreversible martensitic phase transformation occurs, resulting in a permanent step decrease in magnetic permeability. The tag chip detects this change via a magnetic sensing circuit, hardware-locking and rewriting the overload flag in the non-volatile storage area. The reader reads the flag non-contactly to determine the overload history and calculates the real-time tensile force through the antenna resonant frequency deviation. The reader can be equipped with a drone or handheld terminal to automatically record overload information and generate work orders. The backend server integrates the data to achieve lifespan prediction and batch replacement planning. This system is passive, maintenance-free, and tamper-proof, combining overload memory and stress detection to improve the safety and intelligence level of line operation and maintenance.

The present application belongs to the technical field of stamping, and particularly relates to a low-temperature impact-resistant multi-bending stainless steel component progressive die and a stamping method. The die comprises a base, a blanking die and a material punching die arranged on the base, and further comprises a second-stage double-punch bending unit and a third-stage bending unit arranged between the blanking die and the material punching die in sequence. A stainless steel progressive die material plate passes through the blanking die, the second-stage double-punch bending unit, the third-stage bending unit and the material punching die in sequence along a stepping direction to complete the blanking, double-sided punch bending, double-sided bending and material punching processes in sequence, and a multi-bending stainless steel component is obtained. The present application realizes full control of the bending deformation of the multi-bending stainless steel component, effectively prevents local microscopic martensite phase change of the compression strain wrinkle type and the tensile strain crack type, and improves the low-temperature impact service fatigue capacity of the component.

The utility model discloses an automatic control speed quick cooling device, including control speed quick cooling tank and open in the feed port and the discharge port of control speed quick cooling tank two ends, control speed quick cooling tank is equipped with control speed quick cooling mechanism, and control speed quick cooling mechanism includes a plurality of conveying roller, a group of synchronous air cylinder, push board, a group of mounting bracket, a group of guide roller, lower cooling nozzle group, upper cooling nozzle group and a group of pyrometer. The utility model has the beneficial effect that through being equipped with control speed quick cooling mechanism in control speed quick cooling tank, immediately carries out quick cooling to the steel sheet after rolling, makes the steel sheet quick cooling to the phase change temperature 800 about, prevents the growth of austenite grain before phase change, then, reduces water flow at 800, reduces the cooling speed, controls the cooling speed below 15 / s, avoids the austenite to martensite transformation to reduce the steel sheet performance, and the cooling is to 500 air cooling, reaches control speed quick cooling purpose.

This invention provides a method for plasticizing and strengthening TRIP duplex stainless steel, relating to the field of steel material manufacturing technology. The method includes: S1, smelting according to the chemical composition of duplex steel to produce TRIP duplex stainless steel billets; S2, obtaining an initial microstructure with uniform ferrite and austenite distribution; S3, subjecting the initial microstructure to cyclic deformation pretreatment to create a multi-scale structure within the two phases; and S4, performing mechanical property analysis on the pre-deformed TRIP duplex stainless steel. This invention reduces process difficulty by performing cyclic pre-deformation pretreatment on TRIP duplex stainless steel. By preparing a multi-scale structure within the two phases through cyclic pre-deformation, it effectively regulates the strain distribution during tensile deformation, promotes the early, uniform, and stable occurrence of martensitic phase transformation during deformation, and increases the saturation value and transformation amount of martensitic phase transformation. This achieves simultaneous improvement in the strength and plasticity of TRIP duplex stainless steel, effectively enhancing its comprehensive mechanical properties.