73 results about "Stacking-fault energy" patented technology

The invention discloses a high-performance high-entropy alloy and a processing method thereof. Certain content of an element carbon is added into a Fe40Mn40Co10Cr10 alloy to form an interstitial solid solution with a basal body, so that stacking fault energy of the material can be effectively reduced, twin crystals can be induced under the room-temperature condition, and extra strength increment is provided for the basal body by performing solid solution and separating carbides through the element carbon. The element carbon is used as a good interstitial atom and the carbide is used as an effective precipitation strength phase; heat preservation is performed for a relatively long time at a relatively high temperature in the last step, an as-forged microstructure is partly or completely eliminated, and part of the precipitated phase is dissolved to form a nearly single phase structure, so that the alloy has relatively great performance controllable space again on the basis of higher performance level, further strengthening is favorably performed through other strengthening ways such as deformation strengthening and precipitation strengthening to obtain more reasonable strength and plasticity match; and moreover, content of overall alloy elements is reasonable, cost is low, and economical efficiency is relatively strong.

The invention relates to a technology for improving an iron and steel metallic material, in particular to a nitrogen-strengthened high-carbon twin-crystal induced plastic steel material and a method for preparing the same. The steel material is characterized by comprising the following component ranges: 0.2 to 1.0 percent of C, 15 to 35 percent of Mn, 0.04 to 0.2 weight percent of nitrogen content in control, less than 1 weight percent of Al, less than 1 weight percent of Si, less than 0.008 percent of S, less than 0.02 percent of P, and the balance being Fe. The stacking fault energy is controlled to between 20 and 60 mJ.mm<2>. The technology can obtain the proportions of strength and plasticity of different levels through process control so as to obtain the tensile strength of between 995 and 1,530MPa, the yield strength of between 470 and 1,340 MPa and the specific elongation of between 13 to and 71.5 percent. The steel material does not have a turning point of the flexible brittleness. The high-strength high-plasticity steel materials prepared by the technology can be used in the industries such as railway steel rail, saloon sedan manufacturing, engineering machinery, oil-gas delivering pipeline and liquefied natural gas container, military industry, and have important value and great application space.

The invention relates to a preparation method for TWIP steel for a low-cost large-expansibility expansion pipe and a steel pipe. The TWIP steel comprises the chemical components, by weight percentage, 0.30-0.65% of C, 15-30% of Mn, 0.10-1.0% of Cr, 0.01-0.20% of Al, 0.10-1.0% of Si, 0.030-0.30% of Re, S<=0.002%, P<=0.005% and the balance ferrum. Component design is instructed through alloy stacking fault energy, vacuum smelting is conducted, rare earth ferroaluminum is deoxidized, a right amount of Cr and Si elements are added, a small amount of rare earth elements are added, and steel with low content of sulphur and phosphorus and certain grain scale for the large-expansibility expansion pipe is obtained, wherein a base body of the steel is austenite, and the steel has a twinning inducedplasticity effect. The steel is manufactured into large-expansibility large-size expandable casing pipes through hot extrusion.

The invention provides a high-entropy alloy, which relates to the technical field of a metal material. The high-entropy alloy comprises the following elements by atom percentage content: 39.0-41.0% ofFe, 9.0-11.0% of Co, 39.0-41.0% of Mn, and 9.0-11.0% of Cr. A stacking fault energy theoretical value of the high-entropy alloy is 35 mJ/mol, and the stacking fault energy is in favor of keeping a single-phase austenite structure when the high-entropy alloy is placed under environment lower than room temperature; stress load is bear under low temperature condition, dislocation glide and mechanical twining are generated, deformation induces austenite to change to martensite, when the high-entropy alloy is 173 K, the yield strength is 670 M, the stretching rate reaches 62%, and the tensile strength can reach 750 MPa; and the plasticity and intensity are higher than the mechanical properties of a steel product used for low temperature in a traditional method.

The invention discloses a high-forming nitrogen-containing austenitic stainless steel and a manufacturing method thereof. The composition of the steel comprises the following components of, by weight,0.001-0.05% of C, 2.50-3.80% of Si, 6.0-8.0% of Mn, 13.5-15.0% of Cr, 1.0-2.5% of Ni, 0.12-0.15% of N, 3.5-5.0% of Cu, less than or equal to 0.004% of S, 0.1-0.2% of V, 0.1-0.2% of Nb, and the balance Fe and inevitable impurities, wherein C+N is less than or equal to 0.18% , (V + Nb)/C is larger than or equal to 5, the content of Si multiplied by 5.59 mJ/m<2> is greater than or equal to 14 mJ/m<2>, Md30/50 is 40-70 DEG C, the average grain size is larger than or equal to 90 microns, and the hardness is less than or equal to HV180. According to the preparation method disclosed by the invention, the Ni is replaced with nitrogen alloying, and the Mn, the Cu and the like which obtain austenite structures are added; the Si and the like are added, so that lower stacking fault energy is remarkably reduced; the initial hardness of a material is reduced, and the temperature of the MD30/50 is controlled, so that the martensite phase changes slowly in the strain process; the erishen value is larger than or equal to 14.5, LDR is larger than or equal to 2.4, the requirements of complex forming is met, and the performance is close to 304 DDQ with high forming and high cost, so that the steel can be widely applied to industries such as electronics, instruments and apparatus, products and the like.

The invention discloses a high-temperature-resisting silver alloy material. The silver alloy material is prepared through alloy components including, by weight, 80-90 parts of silver, 2-5 parts of copper, 3-5 parts of zinc, 0.2-1 part of cadmium, 0.3-1.2 parts of zirconium, 0.1-0.5 part of indium, 0.2-1 part of beryllium, 0.2-1 part of nickel, 0.3-1.2 parts of magnesium, 0.2-1 part of molybdenum, 0.5-1.5 parts of titanium, 0.3-1.2 parts of cobalt and 0.5-1.5 parts of vanadium. According to the high-temperature-resisting silver alloy material, the stacking fault energy of an alloy matrix is lowered, the diffusion rate of matrix elements is lowered, the effect of strengthening the alloy matrix is achieved, and high temperature resistance of silver alloy is improved; and in the production process, high temperature losses are reduced, and the production cost is greatly reduced.

The invention discloses a biological magnesium alloy containing rich LPSO structures and a preparing method of the biological magnesium alloy. The biological magnesium alloy is obtained in the mannerthat manganese is alloyed to a magnesium alloy with the LPSO structures through an SLM technology, on one hand, the magnesium alloy stacking fault energy is reduced through the manganese element, andintermetallic compound precipitation is reduced while the number of the LPSO structures is increased; and on the other hand, the alloy supercooling degree is increased through the manganese element, grains and the LPSO structures are refined, and the magnesium alloy with the rich, fine and evenly-distributed LPSO structures is obtained. A base body is full of the formed LPSO structures in a parallel lamellar manner, a dense degraded product is formed through preferable degrading, the magnesium base body is protected, and accordingly the degrading resistance of the magnesium alloy is greatly improved.

The invention provides a boron-containing high-entropy alloy coating and a preparation method thereof, and belongs to the field of alloy coatings. Some B atoms are adopted as self-fluxing atoms to be subjected to solid solution in a solid solution body of the face-centered cubic structure, the hardness of the coating is improved, granular and short rod-like M2B hard phases are separated out in a coating base, and due to separation of the hard phases, one one hand, the dispersion strengthening effect is achieved; on the other hand, the solid solution reinforcing effect is lowered, the coating hardness is lowered, and due to the hardness improving effect of dispersion strengthening, solid phase strengthening is greatly offset, the influence of the coating hardness is lowered, finally, the coating hardness is still improved, and a boron element is adopted as a secondary element to be added into high-entropy alloy; due to the gap effect of non-metal elements, the alloy stacking fault energy is improved, lattice deformation is increased, the solid solution strengthening effect is achieved, the non-metal element and the main element can form borides to be dispersed into alloy tissue, the dispersion strengthening effect is generated, and therefore the hardness and corrosion resistance of the high-entropy alloy are improved.

The invention provides a carbonic high-entropy alloy coating and a preparation method thereof, and belongs to the field of alloy coatings. Co, Cr, Cu, Fe and Mn are adopted as main elements, a carbon element (C) is adopted as a secondary element, C is an interval element and is added into the CoCrCuFeMn high-entropy alloy, the stacking fault energy of the alloy can be improved through the interval effect of the non-metal element, lattice distortion of the high-entropy alloy is improved, the solid solution strengthening effect is achieved, the carbon element can form a carbide with the main elements, for example, Fe-C, Cr-C M23C6 or M7C3 carbides are formed and dispersed into alloy tissue, the dispersion reinforcing effect is generated, and the high-entropy alloy hardness and abrasion resistance are improved; meanwhile, the high-entropy alloy structure formed by the main elements is BCC+FCC, a dual-phase solid solution is formed, after the C element is added, and the phase structure type cannot change; due to the dual-phase solid solution, the high-entropy alloy has the higher strength, and the hardness of the carbonic high-entropy alloy coating is improved.

Provided is a high manganese nitrogen-containing steel sheet. The high manganese nitrogen-containing steel sheet according to the present invention comprises 0.5 to 1.0 wt % of carbon, 10 to 20 wt % of manganese, 0.02 to 0.3 wt % of nitrogen, with a remainder of Fe and unavoidable impurities. The high manganese nitrogen-containing steel sheet according to the present invention produces an austenite phase at room temperature, in which the stacking fault energy is effectively controlled by adding chrome and nitrogen. Accordingly, the high manganese nitrogen-containing steel sheet of the present invention produces a mechanical twin during the plastic deformation of the steel sheet, thereby increasing the work hardening rate, tensile strength, and workability.

Steel for low-temperature service having a high degree of surface processing quality comprises: manganese (Mn): 15 wt % to 35 wt %, carbon (C) satisfying conditions of: 23.6C+Mn≧28 and 33.5C−Mn≦23, copper (Cu): 5 wt % or less (excluding 0 wt %), nitrogen (N): 1 wt % or less (excluding 0 wt %), chromium (Cr) satisfying a condition of: 28.5C+4.4Cr≦57, nickel (Ni): 5 wt % or less, molybdenum (Mo): 5 wt % or less, silicon (Si): 4 wt % or less, aluminum (Al): 5 wt % or less, and a balance of iron (Fe) and inevitable impurities. Stacking fault energy (SFE) of the steel is 24 mJ/m² or greater. The SFE is calculated by a formula: SFE (mJ/m²)=1.6Ni−1.3Mn+0.06Mn²−1.7Cr+0.01Cr²+15Mo−5.6Si+1.6Cu+5.5Al−60(C+1.2N)^1/2+26.3(C+1.2N)(Cr+Mn+Mo)^1/2+0.6[Ni(Cr+Mn)]^1/2.

The invention provides a high strength superfine crystalloid copper-germanium alloy and a preparation method thereof. The high strength superfine crystalloid copper-germanium alloy consists of the following components in percentage by mass: 99.89 to 89.85 percent of copper, and 0.11 to 10.15 percent of germanium. The preparation method comprises the following steps of: mixing pure copper and pure germanium in the proportion, smelting, and casting into a copper-germanium alloy bar; performing vacuum annealing, and forging; performing vacuum annealing again to obtain a homogenous microstructure; and immersing in liquid nitrogen for cooling, and forging to obtain the deformation twins-containing high-strength superfine crystalloid copper-germanium alloy. The stacking fault energy of the copper is reduced by adding the germanium element, and a large quantity of deformation twins are introduced, so that the copper-germanium alloy has high strength and excellent mechanical properties. Through the simple preparation process, the copper-germanium alloy with the tensile strength at room temperature of 467-802MPa can be obtained.

The invention discloses a component optimization design method of austenite Fe-Mn-Al-C light alloy steel, and relates to the technical field of metal materials. The component optimization design method comprises the steps that S1, typical chemical components are formulated; S2, thermodynamic and phase diagram calculation is carried out; S3, a corresponding relation graph of the precipitation temperature and calculated SFE is drawn; S4, the chemical components of the alloy are optimized; and S5, chemical component and experiment detection is carried out. The typical chemical components of the alloy steel are formulated on the basis of the chemical component range limited by the austenite Fe-Mn-Al-C light alloy steel, an Olson-Cohen thermodynamic model is selected to calculate the stacking fault energy (SFE) of the typical alloy steel, all the chemical components are optimized, a deformation mechanism of materials can be predicted through the method, the generation content and precipitation temperature of kappa-C carbide are controlled, the strengthening effect of the kappa-C carbide on the austenite light steel is achieved, and a theoretical basis is provided for alloy design and production.

The invention provides high-strength high-plasticity TWIP steel and a preparation method thereof. The technical scheme is that: aimed at the defects that higher strength and higher plasticity are notliable to achieve through single of twinning strengthening and nano precipitation strengthening in steel, the invention provides the preparation method of utilizing alloy elements like Cu, Ni and Al to replace a part of Mn to improve stacking fault energy, promote the TWIP effect, stabilize austenite, inhibit martensite phase transformation and refine twining structure on the basis that smelting,homogenization and delayed cracking problems due to high Mn content in TWIP steel are comparatively studied; and size, density and distribution of nano rich Cu particles and NiAl particles generated in steel are controlled through a strong magnetic field, and strength of TWIP steel is improved under the precondition that plasticity and toughness are not reduced.

A method for evaluating the deformability of a nickel-based alloy containing composite point defects. Considering the influence of vacancy and solute atoms on the generalized stacking fault energy ofnickel-based alloys, Fully considering the establishment of supercell model, the deformability of Ni-based alloys with composite point defects is evaluated by the calculation of generalized stacking fault energy. The method includes the following steps: firstly, determining the most stable relative positions of vacancies and solute atoms in Ni-based alloys; secondly, establishing a supercell modelfor calculating that generalize stacking fault energy of the nickel-based alloy; thirdly, the generalized stacking fault energy of Ni-based alloys containing vacancies and solute atoms being calculated; in the fourth step, the plastic deformation behavior is evaluated according to the generalized stacking fault energy. The invention fully considers the important parameters which can influence thestructure model when establishing the model, including the vacuum layer thickness, the atomic layer number and the relaxation system, effectively prevents the calculation result deviation caused by the unreasonable structure model in the calculation process of the generalized stacking fault energy, improves the calculation efficiency and reduces the calculation cost.

Provided is a welding joint having remarkable impact resistance and abrasion resistance. The welding joint having remarkable impact resistance and abrasion resistance comprises 0.02-0.75 wt % of C, 0.2-1.2 wt % of Si, 15-27 wt % of Mn, 2-7 wt % of Cr, 0.025 wt % or less of S, 0.025 wt % or less of P, 0.001-0.4 wt % of N, and the balance of Fe and other inevitable impurities, and having a stacking-fault energy of 15-40 mJ/m² at 20° C. Further provided are a welding joint having remarkable low temperature impact toughness and abrasion resistance, and a welding joint very preferably applied to a slurry pipe and the like used in the oil sand industry field related to oil production.

Provided are an aluminum alloy having an adjusted microstructure in an aluminum matrix or an aluminum alloy matrix for high elongation percentage or high strength and a method of fabricating the same. The aluminum alloy includes an aluminum-based matrix; and a nonmetal element solidified in the aluminum-based matrix, wherein stacking fault energy of the aluminum alloy is decreased compared to that of pure aluminum.

The invention relates to high-strength and high-toughness wear-resistant steel and a preparation method for nano twin crystal reinforcement and toughening of high-strength and high-toughness wear-resistant steel. The steel comprises the components in percent by mass: 0.35%-0.85% of C, 15.2%-24.8% of Mn, 0.1%-0.5% of Si, smaller than or equal to 1.0% of Al, smaller than or equal to 0.005% of S, smaller than or equal to 0.01% of P, 0.5%-1.5% of Nb, 0.2%-0.8% of Ti, 0.2%-0.75% of V, 0.005%-0.05% of N, 0.02%-0.1% of rare earth RE and the balance Fe and inevitable impurities. The stacking fault energy of an alloy is 24-30 kJ/m <2>, and the mass percent of the addition amount of Ti, Nb and V is 2: 1: 1. The preparation process comprises the steps of alloy smelting and negative pressure casting, homogenization heat treatment and cogging, hot rolling, nanometer twinning treatment, nanometer twinning stabilization and low-temperature aging treatment. According to the invention, fine structure regulation and control are carried out based on means of deformation and heat treatment by means of low fault energy and microalloying component optimization matching design, so that good structure matching is realized, and the alloy has high strength, high toughness and high wear resistance. The wear-resistant steel is excellent in comprehensive mechanical property, low in alloy cost, simple in preparation process, low in production and manufacturing cost and easy to put into industrial production and large-scale industrial equipment.