19 results about "Stacking-fault energy" patented technology

This invention discloses a high-strength and high-toughness high-manganese steel plate for ultra-low temperatures and its preparation method. Its chemical composition and mass percentages are: C 0.04–0.10%, Mn 21.0–25.5%, Si 0.25–0.35%, P≤0.008%, S≤0.003%, O≤0.003%, Ti 0.02–0.05%, W 0.01–0.05%, with the balance being Fe and unavoidable impurities. The high-manganese steel plate has a stacking fault energy of 40–45 mJ / m at -196℃. 2 This steel plate achieves its design by controlling the stacking fault energy to 40–45 mJ / m. 2 This ensures that the steel undergoes a strong TWIP effect in the subsequent heavy impact pre-hardening step, forming a gradient nanocrystalline layer on the steel surface, which significantly improves the yield and tensile strength of the steel; it can improve the uniformity of the internal structure of the steel plate and significantly improve the low-temperature impact toughness of high manganese steel, with an impact toughness AKV≥200J at -196℃.

The application discloses an ultralow-temperature steel and a heat treatment process and application thereof, and relates to the technical field of ultralow-temperature steel. ‑2 The ultralow-temperature steel comprises the following components in percentage by mass: C: 0.41% to 0.45%, Mn: 23.5% to 24.5%, Cr: 3.5% to 3.7%, Cu: 0.35% to 0.45%, Ni: 0.55% to 0.65%, V: 0.20% to 0.24%, Mo: 0.20% to 0.24%, Si: 0.15% to 0.25%, Al: 0.02% to 0.04%, and the balance of Fe and inevitable impurities; the ultralow-temperature steel is full austenite structure, and the stacking fault energy of the ultralow-temperature steel is 18 to 21 mJ·m ‑2 at-269 DEG C. The ultralow-temperature steel has multiple properties of excellent ultralow-temperature resistance, corrosion resistance and hydrogen damage resistance through the specific heat treatment process and the component composition, can be applied to the storage and transportation of ultralow-temperature medium such as liquefied natural gas and liquid hydrogen, and is suitable for complex environments such as land, sea and aviation.

The invention relates to a low-fault-energy micro-twin synergistic deformation cobalt-based alloy and a preparation method thereof, and belongs to the field of cobalt-based high-temperature alloys. According to the alloy, on the basis of Co-Al-W, Ti and Ta which are smaller than or equal to 4 wt% are added according to calculation of a first principle, and the stacking fault energy is controlled to be-95 mJ / m < 2 > to-89 mJ / m < 2 > (0K). Aiming at the defect of insufficient high-temperature plasticity of the gamma '-phase strengthened cobalt-based alloy, an electronic structure is accurately regulated and controlled through a first principle, intrinsic stacking fault energy is designed to reach an optimal negative value interval, a micro-twin mechanism is activated, dislocation slippage and micro-twin coordination is realized, and the problem of sudden plasticity drop caused by single deformation mechanism (dislocation slippage leading) and grain boundary weakening of a traditional alloy is solved; the high-temperature strength and the plasticity are synchronously improved.

The invention belongs to the technical field of shape memory alloys, and particularly relates to a shape memory alloy with excellent cold working performance and a preparation method and application thereof. According to the shape memory alloy provided by the invention, stacking fault energy is reduced by replacing solid solution and / or grain coarsening and grain refining are inhibited, so that the alloy structure is more uniform, Mn is added to reduce the stacking fault energy by replacing solid solution, meanwhile, MnN is added, Ti and Hf can replace Mn in MnN out, nano TiN and HfN are formed, dislocation movement is hindered, and the strength of the shape memory alloy is improved; the shape memory alloy with excellent austenite phase transition temperature (Af) and plastic comprehensive performance is obtained by further regulating and controlling the use amount of Hf with high melting point and large atomic radius and the use amount of Mn and MnN. Therefore, the technical problem that an existing Ni-Ti-Hf shape memory alloy is low in cold machining performance is solved.

The application discloses a kind of high-damping Fe-Mn series alloy materials, the component of alloy and the mass fraction of each component are as follows: Mn 16.5-17.5%, doping metal 0.5-0.8%, TiB2 0.02-0.03%, C0.01-0.015%, Si 0.015-0.02%, Fe remainder.The high-damping Fe-Mn series alloy material provided by the application, by optimizing the composition of alloy material and improving the process, using the method of combination of forging, stage solid solution and stage aging, the Fe-Mn series alloy material prepared has the comprehensive performance of high damping, high strength and good toughness;Add specific ratio of Ni, Zr, Mo doping metal and a small amount of TiB2, wherein, Ni improves the stacking fault energy, stabilizes austenite and solid solution strengthening, Zr and Mo form intermetallic compound to carry out precipitation strengthening and refine grain, TiB2 promotes grain refinement, C and Si affect the strength, plasticity and processing performance of alloy, synergistic effect of each element, the balance of high damping, high strength and good low-temperature toughness of Fe-Mn series alloy is realized.

The invention discloses a method for preparing a dual-phase heterogeneous deformation mechanism tin bronze alloy through stacking fault energy-oriented Sn content regulation and control and the alloy, and relates to the technical field of metal materials. The method comprises the following steps: determining a critical component window of a low-Sn glide region and a high-Sn twinborn region on the basis of an influence rule of Sn content on an alpha-Cu solid solution stacking fault energy and a deformation mechanism; through the combination of melt instantaneous cooling induced nucleation and a rheological extrusion forming process, the synergistic distribution of two phases on the microscopic scale is realized in the tin bronze alloy. In the plastic deformation process of the obtained tin bronze alloy, dislocation slippage is used as a dominant deformation mechanism in a low-Sn area, mechanical twinning is used as a dominant deformation mechanism in a high-Sn area, and a heterogeneous deformation coordination mechanism is formed. The alloy prepared through the method shows excellent strength and toughness, and therefore a new path is provided for design and preparation of the high-performance copper alloy.

This invention discloses a novel ultra-thin strip of 301 stainless steel and its preparation method, belonging to the field of advanced high-strength steel technology. The strip composition by mass percentage is: 0.1–0.2% C, 0.4–0.5% Si, 1–2% Mn, 1–1.5% Al, 15–18% Cr, 8.0–9.0% Ni, 0.1–0.2% Mo, with the balance being Fe and impurities. The preparation method involves: forging the steel ingot at 1100℃–1200℃, followed by low-temperature hot rolling at 600℃–800℃, pickling, and then cold rolling at 150℃–200℃ with a pulsed current, resulting in a reduction of 90%–95%. This invention improves stacking fault energy through compositional regulation, inhibits martensitic phase transformation, and induces twinning deformation; the pulsed current promotes regular dislocation movement; and the Al element grain boundary segregation forms a micro / nano layered structure, achieving a synergistic effect of twin refinement and layered toughening. The resulting ultra-thin strip has a tensile strength of 1100MPa to 1200MPa and an elongation of 40% to 50%, overcoming the contradiction between strength and plasticity, and is suitable for high-performance elastic components in the fields of electronics and aerospace.

The invention discloses a design method for cooperatively screening a high-dynamic-toughness refractory high-entropy alloy based on molecular simulation. The method comprises the following steps: 1, determining candidate elements and component spaces in the refractory high-entropy alloy; 2, constructing an initial atomic model; 3, determining a generalized fault energy curve; 4, calculating heat conductivity; 5, screening components and establishing performance criteria; and 6, experimental verification. According to the method, the dynamic toughness of the refractory high-entropy alloy is predicted and screened by taking two key parameters gamma usf--a dominant deformation mechanism and k--a dominant thermal softening behavior as quantitative indexes of collaborative screening and establishing a collaborative relationship of the key parameters gamma usf--the dominant deformation mechanism and the k-the dominant thermal softening behavior; two most core physical essence influencing the dynamic toughness of the BCC structure refractory high-entropy alloy are grasped, and the spanning from'empirical design 'to'physical mechanism driven design' is realized.

This invention discloses a method for predicting solid solution strengthening of multi-principal element alloys considering both elastic and chemical contributions. Relating to the field of computational metallurgy, the method incorporates both the elastic contribution due to atomic size / modulus mismatch and the chemical contribution due to local fluctuations in stacking fault energy within a unified thermally activated dislocation slip framework. It combines the Peierls-Nabarro model with particle swarm optimization to perform a refined solution for the dislocation core structure, establishing a quantitative correlation between alloy composition, dislocation core structure, dislocation-solute interaction energy, thermal activation energy barrier, and critically resolved shear stress. This technical solution achieves accurate prediction of critically resolved shear stress in the 0K to room temperature range and provides a theoretical tool for performance evaluation and composition optimization of low-temperature high-strength, high-toughness FCC multi-principal element alloys.

This invention belongs to the field of metallic materials technology, specifically a method for designing the chemical composition of low-temperature resistant high-manganese steel forgings. The invention comprises the following alloying elements by mass percentage: C: 0.40%~0.50%, Si: 0.11%~0.22%, Mn: 22.50%~25.50%, Cr: 3.00%~4.00%, Mo: 0.30%~1.00%, V: 0.03%~0.20%, Ti: 0.03%~0.10%, Al: 0.01%~0.10%, P≤0.020%, and S≤0.005%, with the remainder being Fe and unavoidable impurities. In its implementation, this invention comprehensively considers the influence of factors such as the nickel equivalent, chromium equivalent, and stacking fault energy of high-manganese steel, providing a systematic quantitative design method for manganese steel. This method can not only guide the design and development of low-temperature resistant high-manganese steel but can also be extended to the research and development of other new steels by specifying different quantitative value ranges.

The application provides a kind of metal powder for magnetic force combined 3D printing, the metal powder is austenitic steel metal powder, substantially non-magnetic in initial state, can produce magnetism after stress, and can recover to substantially non-magnetic again after heat treatment.The application also provides a kind of preparation method of metal powder for magnetic force combined 3D printing, including designing material composition, making martensite start transformation temperature lower than 3D printing powder laying temperature, the highest temperature of strain-induced martensitic transformation higher than 3D printing powder laying temperature, stacking fault energy greater than or equal to 18mJ / m 2 , nickel equivalent and chromium equivalent are in austenite phase region on Schaeffler diagram;According to the designed composition, melt the metal material;The melted metal is made into metal powder;Solution treatment and water quenching treatment obtain substantially non-magnetic metal powder;Make the powder produce magnetism after stress.The metal powder prepared by the application can meet the requirements of magnetic force combined 3D printing, and is easy to realize industrialized preparation.

The invention discloses a high-strength plastic laminated composite steel component process design method based on machine learning. The method comprises the following steps: step 1, data acquisition; 2, dividing a data set; 3, establishing a machine learning algorithm model; 4, optimization design of the layered composite steel and iron material; and 5, evaluating and selecting a design result. According to the method, the relationship among components, process, tensile strength and elongation at break is established by applying an integrated learning algorithm (GBR) and a physical metallurgy model, and the strength and plasticity are subjected to optimization design quickly and accurately in an original data set range by means of a genetic algorithm (GA). A large number of obtained design results are verified and screened through a strengthened physical model, a fault energy physical model and Thermal-Calc software calculation, high-reliability design results are screened out, and a complete high-performance layered composite steel and iron material data driving design platform is formed.

The invention provides a ceramic coating structure and a preparation method thereof. The ceramic coating structure includes: a substrate; a transition layer disposed on the substrate; the transition layer is arranged on the substrate, the ceramic coating is arranged on the transition layer, the transition layer is formed by alternately depositing at least one first metal layer and at least one second metal layer, the surface of the substrate is in direct contact with the lowermost first metal layer serving as the transition layer, and the uppermost second metal layer serving as the transition layer is in direct contact with the ceramic coating. The ratio of the larger one to the smaller one of the stacking fault energy of the first metal layer and the stacking fault energy of the second metal layer is greater than 3; the lattice mismatch degree between the first metal layer and the second metal layer is greater than 2% and less than 15%; and the ratio of the thermal expansion coefficient of the second metal layer to the thermal expansion coefficient of the first metal layer is greater than 1.2 and less than 5.

The invention discloses a method for inhibiting fierce sawtooth rheology of a high-temperature alloy containing interstitial atoms, the formation of mechanical twin crystals of the high-temperature alloy in a plastic deformation process is inhibited by improving the stacking fault energy of the alloy, so that the fierce sawtooth rheology phenomenon is inhibited, and the improvement of the stacking fault energy is realized by adjusting the alloy components of the high-temperature alloy containing the interstitial atoms. The stacking fault energy is improved through component design, and the microscopic deformation mechanism of the material is changed from the source, so that the material is converted into a more stable dislocation slippage dominant mode from a twinning dominant mode which is easy to cause severe sawtooth rheology, and excellent mechanical stability and fatigue performance are macroscopically obtained.

This invention discloses a cryogenic steel, its rolling method, and its applications. This cryogenic steel uses C, Mn, Mo, and Si as alloying elements, exhibiting an austenitic structure with suitable stacking fault energy. It possesses high strength and high ductility at -269℃, making it suitable as a high-strength material for cryogenic environments such as superconducting coil armor and liquid helium container materials. Compared to stainless steel under the same operating conditions, it has higher strength and does not contain Ni, thus improving the material's economic efficiency.

The application relates to the material field and relates to an amorphous composite material and a preparation method thereof. a Cu b Al4Ag1Sn 0.75 , 43<=a<=55.25, 39<=b<=51.5; a+b=94.25; the amorphous composite material controls the thermodynamic precipitation enthalpy of the austenite phase B2-CuZr by regulating the molar ratio of alloy atoms Zr and Cu, simultaneously reduces the stacking fault energy of the martensitic phase transformation of the austenite phase B2-CuZr, and improves the martensitic phase transformation capacity of the austenite phase B2-CuZr. The austenite phase B2-CuZr in the amorphous composite material absorbs a large amount of strain energy by undergoing martensitic phase transformation in the deformation process, and the austenite and the martensite can hinder the expansion of shear bands in the amorphous matrix and promote the proliferation of shear bands, so that good plasticity and work hardening capacity are obtained, and the toughness and plasticity of the amorphous composite material are significantly improved.

This application relates to a copper-containing low-density steel and its preparation method, belonging to the field of steel materials technology. The chemical composition of the low-density steel, by mass fraction, is: C: 0.80%~0.95%, Mn: 15%~18%, Al: 5%~7%, Cu: 1%~2%, P≤0.01%, S≤0.01%, N≤0.004%, with the remainder being Fe and unavoidable impurities. The microstructure of the low-density steel includes austenite, κ-carbides, and an ordered B2 phase. Through a multi-element alloying design with high C, high Mn, high Al, and high Cu, the aim is to precisely control the austenite stacking fault energy to synergistically stimulate the twinning-induced plasticity effect and plane slip mode during deformation. Simultaneously, utilizing the aging precipitation characteristics of Cu, a nanoscale ordered B2 phase is formed after solution treatment and aging, achieving a good match between precipitation strengthening and plasticity. The resulting low-density steel achieves significant weight reduction while possessing ultra-high strength, high elongation, and excellent work hardening ability.

This invention provides a low-cost, ultra-low temperature, high-toughness high-manganese steel for liquid hydrogen storage tanks and its preparation method, relating to the technical field of low-temperature steelmaking. The chemical composition of the high-manganese steel, by mass percentage, is: C 0.37-0.47%, Mn 26-30%, Al 2.7-3.3%, P≤0.01%, S≤0.001%, with the remainder being Fe and unavoidable impurities; wherein the microstructure consists of a single-phase austenite structure, with an average austenite grain size of 14-18 μm. This invention regulates stacking fault energy by designing the alloy composition, and simultaneously ensures a single, uniform austenitic structure through high-temperature homogenization, hot rolling, and solution treatment. These two processes synergistically enhance the material's strength, plasticity, and impact toughness at extremely low temperatures of -269℃. At -196℃, the steel exhibits a tensile strength ≥1171 MPa, elongation after fracture ≥93.1%, strength-ductility product ≥109 GPa%, and Charpy impact toughness ≥239 J. At -269℃, the steel exhibits a tensile strength ≥1410 MPa, elongation after fracture ≥64.5%, strength-ductility product ≥91 GPa%, and Charpy impact toughness ≥233 J.

The present application relates to the technical field of multi-element precious metal-based high-temperature alloy, and discloses a multi-element precious metal-based high-temperature alloy steady-state creep rate prediction method based on multi-scale integrated calculation, which comprises the following steps: S1: crystal structures of the multi-element precious metal-based high-temperature alloy and intermetallic compounds are respectively constructed to obtain thermal physical properties of lattice constants, shear moduli, Poisson's ratios, stacking fault energies, diffusion activation energies and diffusion pre-exponential factors; S2: according to the CALPHAD method, the composition-dependent elastic moduli, stacking fault energies and lattice constant thermal physical properties of the multi-element precious metal-based high-temperature alloy are calculated; S3: the thermal physical properties of the multi-element precious metal-based high-temperature alloy single-phase fixed component in S1 and the composition-dependent thermal physical properties in S2 are respectively substituted into a steady-state creep rate model to respectively predict the steady-state creep rates of the multi-element precious metal-based high-temperature alloy changing with temperature and changing with composition. The present application can shorten the research and development cycle of the alloy and reduce experimental costs.