377 results about "Solid solution strengthening" patented technology

The invention discloses a formula, a coating and a method of a dual in-situ precipitation reinforced FeCoNiCr-based high-entropy alloy composite material with a low corrosion-wear synergistic effect. The Al-Co-Cr alloy material comprises the following components in atomic percent: 15 to 30 at% of Al, 10 to 25 at% of Co, 10 to 25 at% of Cr, 10 to 25 at% of Fe, 10 to 25 at% of Ni, 20 to 35 at% of Ti and 5 to 15 at% of C, the preparation method comprises the following steps: filling all metal powder and graphene powder into a ball-milling tank, adding grinding balls, filling argon, sealing, and ball-milling, so as to obtain mixed powder in which the surfaces of metal powder particles are uniformly coated with graphene. The high-entropy alloy composite material with high hardness, high wear resistance and high corrosion resistance is obtained by utilizing the solid solution strengthening effect and the multiple in-situ precipitation strengthening effect of micron-scale TiC and nano-scale precipitation B2. The prepared coating is uniform and compact in structure, is metallurgically bonded with a base material, and has excellent corrosion and friction resistance and low corrosion-wear synergistic effect.

The invention belongs to the field of stainless steel. Specifically, the invention relates to soft magnetic stainless steel containing Cr, Cu, Mo, Nb and rare earth elements, and a soft magnetic stainless steel profile and a product prepared from the soft magnetic stainless steel. The Cu element contained in the soft magnetic stainless steel can be separated out to form nano Cu when the soft magnetic stainless steel is subjected to aging treatment, so that the mechanical property of the obtained soft magnetic stainless steel profile can be effectively improved, and the soft magnetic stainless steel profile has excellent low-temperature toughness and soft magnetic property; in addition, microalloy precipitation is optimized through Nb and rare earth element compounding, so that the proper fine grain size is obtained, and the soft magnetic stainless steel profile has excellent low-temperature toughness; and meanwhile, the tensile strength of the soft magnetic stainless steel profile is improved through the solution strengthening effect of Mo, and the corrosion resistance of the soft magnetic stainless steel profile is improved. The soft magnetic stainless steel profile can be effectively applied to electromagnetic valves and related products which serve in low-temperature media and require certain strength, and has good popularization prospects and application value.

The invention relates to the technical field of magnesium alloys, in particular to a high-toughness rare earth-containing magnesium alloy and a preparation method thereof.The high-toughness rare earth-containing magnesium alloy is prepared from, by weight, 3-8 parts of Zn, 1-5 parts of RE, 0.5-3 parts of Al, 0.1-1 part of Mn, 0.05-0.3 part of Zr and the balance Mg; rE is a combination of Y, Nd and La in a mass ratio of (2-3): 1: (0.5-1). Zinc is used as a secondary main element to replace part of aluminum, efficient solid solution strengthening is achieved through high solid solubility of zinc in magnesium, meanwhile, the morphology and distribution of a precipitated phase are regulated through rare earth, a beta-MgZn2 phase is formed, the high-temperature stability is better, balance optimization of strength, toughness and corrosion resistance is achieved, meanwhile, the welding performance of the alloy is improved through combination of Y, Nd, La and Zr, and the welding performance of the alloy is improved. The hot crack tendency is reduced, the brittle phase problem of a traditional high aluminum alloy is avoided, and the corrosion resistance and the machining performance are synergistically improved.

The invention discloses a double-gradient high-temperature-resistant high-entropy alloy wear-resistant layer and an ultrasonic-assisted laser cladding preparation method thereof, and belongs to the technical field of metal material coatings and surface modification. A proper amount of refractory element W with anti-oxidation and solid solution strengthening effects is introduced into a CoCrFeNi high-entropy alloy coating, an ultrasonic-assisted laser cladding process is adopted, the wear-resistant layer with the grain size and the precipitated phase volume fraction in a gradient structure from exterior to interior is prepared, local stress concentration caused by W aggregation in the laser cladding process is improved, and the wear-resistant performance of the CoCrFeNi high-entropy alloy coating is improved. And the metallurgical bonding strength of the cladding layer and the matrix is improved, and the high-temperature friction and wear resistance of the cladding layer is enhanced. The cladding layer is fine and compact in structure, in gradient distribution, good in mechanical property and excellent in high-temperature wear resistance. The method is easy to operate and low in cost, and an effective method is provided for improving highly coordinated regulation of process-structure-performance and preparing the novel high-temperature-resistant high-entropy alloy wear-resistant layer.

The invention provides a method for additive forming of a high-performance Ti2AlNb three-period minimal curved surface lattice structure in a nitrogen atmosphere, and belongs to the technical field of additive manufacturing. Comprising the following steps: step 1) modeling an implicit function of a TPMS configuration: designing a CAD model of the TPMS configuration and exporting the CAD model as an STL file; 2, pretreatment of the Ti2AlNb lattice structure formed through L-PBF, wherein an STL file is subjected to slicing treatment, and technological parameters are set; 3, L-PBF forming of the Ti2AlNb lattice structure is conducted, specifically, in the nitrogen-argon mixed atmosphere, the Ti2AlNb lattice structure is formed through the L-PBF technology; and (4) the TPMS configuration Ti2AlNb lattice structure is subjected to surface treatment. According to the method, the Ti2AlNb lattice structure with the TPMS configuration is designed through implicit function modeling, the Ti2AlNb lattice structure with the TPMS configuration is formed through L-PBF in the nitrogen-argon reaction atmosphere, the problems that in traditional particle strengthening, reinforcements are distributed unevenly, and the solid solution strengthening effect is limited are solved, and good matching of the strength, plasticity and toughness of the lattice structure is achieved.

The invention discloses a nickel-based single-crystal high-temperature alloy with high structure stability and a preparation method thereof, and relates to the technical field of high-temperature alloys. The nickel-based single crystal high-temperature alloy provided by the invention is prepared from the following components in percentage by mass: 5 to 7 percent of Al, 7.5 to 10 percent of Co, 5 to 7 percent of Cr, 0.1 to 0.2 percent of Hf, 0 to 2 percent of Mo, 5.5 to 7.5 percent of Ta, 0 to 1 percent of Ti, 8 to 10 percent of W, 0.02 to 0.05 percent of C, 0.003 to 0.005 percent of B and the balance of Ni. According to the invention, by controlling the ratio of elements and avoiding the addition of Re, the precipitation temperature of a harmful TCP phase is obviously reduced to about 840 DEG C on the basis of maintaining a sufficient solid solution strengthening effect, and the long-term stability of the structure is greatly improved. The high-temperature mechanical property of the alloy provided by the invention reaches the level equivalent to that of a traditional Re-containing second-generation single-crystal alloy and is remarkably superior to that of foreign Re-free single-crystal alloys MD2 and Rene N500, and the nickel-based single-crystal high-temperature alloy with high structure stability successfully realizes the unification of low cost and high performance, and is suitable for industrial production. And a reliable material solution is provided for manufacturing the heavy-duty gas turbine blade with higher market competitiveness.

The invention relates to the field of metal material surface strengthening, in particular to an in-situ reaction multi-element ceramic phase reinforced titanium-based composite coating and a preparation method thereof. The preparation method comprises the steps that titanium alloy powder and B4C powder are mixed, and mixed powder is obtained; the mixed powder is conveyed to a cladding focus under atmosphere protection, reaction gas is introduced, laser cladding is conducted, and the in-situ reaction multi-element ceramic phase reinforced titanium-based composite coating is formed on the surface of the metal sample; the reaction gas is nitrogen; the laser power is 1-2 kW, the scanning speed is 5-20 mm / s, and the multi-pass cladding lap joint rate is 40%-80%. By regulating and controlling the laser cladding process, optimizing the laser power, the scanning speed and the reaction gas flow and utilizing a dispersion strengthening mechanism and a solid solution strengthening mechanism of a ceramic phase generated through in-situ reaction, the hardness and the wear resistance of the composite coating are improved, the problems that a traditional titanium-based coating is low in hardness and poor in wear resistance are effectively solved, and the service life of the coating is prolonged. The method is suitable for surface strengthening of key components in the fields of aerospace, ocean engineering and the like.

The invention provides a friction-resistant high-entropy alloy composite coating and a preparation method thereof, and belongs to the technical field of metal surface modification. A FeCoCrNiMox (x is greater than or equal to 0.18 and less than or equal to 0.25) high-entropy alloy is taken as a main component of composite powder, graphene is taken as an additive phase, and the FeCoCrNiMox high-entropy alloy composite coating is prepared on the surface of a matrix by adopting a laser cladding method. The graphene added in the composite powder can generate carbides in situ under the action of laser cladding, and second phase strengthening, solid solution strengthening and fine grain strengthening are generated, so that the friction resistance of the surface of the matrix is remarkably improved. The preparation method is easy to operate and low in cost, the prepared composite coating is high in bonding strength, good in toughness and plasticity and excellent in friction resistance, the surface performance of equipment can be effectively improved, safe and stable operation of the equipment is guaranteed, the service life of the equipment is prolonged, and maintenance expenditure is reduced.

The invention discloses a method for improving the quality of a laser cladding refractory high-entropy alloy coating, and belongs to the technical field of alloy coatings. The refractory high-entropy alloy coating is composed of WMoTaNb and hydride of Ti or V, the refractory high-entropy alloy coating is a single BCC phase, and the refractory high-entropy alloy coating is prepared through coaxial powder feeding laser cladding. The laser cladding refractory high-entropy alloy coating prepared through an introduction method (solid solution strengthening and in-situ deoxidation) has excellent wear resistance and high-temperature oxidation resistance, the quality and performance of the refractory high-entropy alloy coating are improved through additional powder, and the microhardness of the section of the refractory high-entropy alloy coating reaches up to 674.52 HV0. 2. The coating can be applied to the fields of aerospace, nuclear reactors and the like.

The invention discloses high-temperature-resistant high-entropy stainless steel and a preparation process and application thereof, and relates to the technical field of stainless steel. The high-temperature-resistant high-entropy stainless steel comprises the following components: 0.03 to 0.15 weight percent of C, 0.08 to 0.30 weight percent of N, less than or equal to 1.0 weight percent of Si, less than or equal to 3.0 weight percent of Mn, less than or equal to 0.015 weight percent of S, less than or equal to 0.035 weight percent of P, 16.0 to 22.0 weight percent of Cr, 9.0 to 14.0 weight percent of Ni, 0.18 to 3.6 weight percent of microalloy elements, 0.04 to 4.0 weight percent of Mo, 0.05 to 0.80 weight percent of Co and 0 to 0.10 weight percent of RE. According to the technical scheme, C, N and microalloy elements such as Ti, Zr, Hf, Ta, V, W and Nb can form nanoscale second-phase precipitates in crystals, the solid solution strengthening and precipitation strengthening effects can be achieved, and the high-temperature strength of the material is remarkably improved.

Tungsten powder, molybdenum powder, titanium carbide powder and tungsten-copper composite powder are mixed to obtain mixed powder, the mixed powder is pressed and formed to obtain a formed blank, the formed blank is sintered to obtain a ceramic reinforced tungsten framework, the ceramic reinforced tungsten framework is subjected to copper infiltration treatment, and the tungsten-infiltrated copper material is obtained. Titanium carbide and molybdenum are introduced when the tungsten framework is sintered, the strength of the tungsten framework is effectively improved through the solid solution strengthening effect of molybdenum and the second phase strengthening effect of titanium carbide, then the high-temperature strength of the tungsten infiltrated copper material is remarkably improved, meanwhile, the density of the material can be reduced, and weight reduction of tungsten infiltrated copper is achieved. Besides, in the process of sintering the ceramic reinforced tungsten framework, superfine tungsten-copper composite powder is introduced, the sintering performance of the tungsten framework can be remarkably improved, the subsequent copper infiltration effect can be optimized, and therefore the tungsten infiltrated copper material is uniform in component structure, the ablation resistance of the light ablation-resistant tungsten infiltrated copper material is excellent, and the density is greatly reduced compared with existing tungsten infiltrated copper.

The invention discloses nodular cast iron and a production process, and relates to the technical field of nodular cast iron preparation. The invention discloses a nodular cast iron production process. Carbon steel scrap and recirculated iron are used as main furnace materials for smelting, a spheroidizing agent and a first nucleating agent are added for a spheroidizing reaction, pouring is conducted, stream secondary inoculation is conducted, solidification cooling and heat treatment are conducted, and a casting is formed. The process route of the nodular cast iron production process is different from that of a foreign high-silicon solid solution strengthening process route for improving the elongation rate, pig iron is not adopted, only waste steel and recirculated iron are used as main raw materials, and the prepared nodular cast iron meets the requirements of casting products for high strength and high elongation rate of nodular cast iron at the same time; and no precious alloy is added in the production process, so that the production cost is greatly reduced, and the economic benefit is remarkably improved.

The invention relates to the technical field of alloy powder preparation, and particularly discloses alloy powder for laser surfacing and a preparation method thereof, and the alloy powder for laser surfacing comprises 8-12% of nickel (Ni), 4-6% of chromium (Cr), 2-3% of molybdenum (Mo), 1-2% of boron (B), 10-15% of titanium carbide (TiC), 0.5-1% of yttrium oxide (Y2O3), 0.5-1% of silicon (Si), 0.1-0.3% of carbon (C) and the balance of iron (Fe). Fe is used as a matrix, corrosion-resistant and solution strengthening elements such as Ni, Cr and Mo are accurately matched, a low-content Y2O3 rare earth element and a TiC nano strengthening phase are introduced, Y2O3 effectively inhibits grain coarsening in the surfacing process, the brittleness problem caused by the traditional high rare earth content is avoided, TiC nano particles are evenly dispersed in the matrix and form a composite strengthening structure with a Cr7C3 hard phase, the hardness of a surfacing layer is improved, and the hardness of the surfacing layer is improved. The wear-resistant life is prolonged.

The invention discloses a high-strength and high-plasticity Ti2AlNb alloy additive preparation method. The high-strength and high-plasticity Ti2AlNb alloy additive preparation method comprises the following steps that firstly, scanning parameters are set; 2, prefabricating a solid sheet layer; 3, in-situ heat treatment; and 4, preparing the component. According to the preparation method, through slicing and layering treatment, by means of a slice layer alternate merging melting scanning mode, overheating and remelting of adjacent slice layers are effectively avoided, and the structure stability and the mechanical property are greatly improved; the in-situ heat treatment is beneficial to exerting the effects of phase boundary strengthening and solid solution strengthening, the metallurgical bonding strength of lamellas can be improved, the structure and performance difference caused by lamellar remelting is solved, the plasticity of the Ti2AlNb alloy is remarkably improved on the premise that the excellent strength of the Ti2AlNb material is kept, the room-temperature tensile strength of the prepared Ti2AlNb alloy is not lower than 1100 MPa, the yield strength is not lower than 990MPa, and the tensile strength of the prepared Ti2AlNb alloy is not lower than 10MPa. The plasticity is not lower than 6%, and the method has a wide application prospect in the field of aerospace equipment.

The invention discloses a solid solution strengthening type difficult-to-deform nickel-based high-temperature alloy strip and a preparation process thereof, and belongs to the technical field of nickel material processing. The solid solution strengthening type difficult-to-deform nickel-based high-temperature alloy strip prepared by the invention comprises the following components in percentage by mass: 0.07 to 0.08 percent of carbon, 0.33 to 0.35 percent of silicon, 0.46 to 0.48 percent of manganese, 21.7 to 22.3 percent of chromium, 0.05 to 0.06 percent of cobalt, 0.34 to 0.36 percent of aluminum, 1.30 to 1.31 percent of molybdenum, 0.26 to 0.27 percent of iron, 13.85 to 13.86 percent of tungsten, 3.23 to 4.40 percent of titanium and the balance of nickel. The preparation method comprises the following steps: melting silicon, manganese, chromium, molybdenum, iron, cobalt, tungsten and nickel in a vacuum induction melting furnace, refining and deoxidizing; after deoxidation, adding carbon, aluminum and titanium under the conditions of argon protection and laser irradiation, stirring, discharging, casting, solidifying and homogenizing; and then cogging forging is carried out, after high-temperature rolling is carried out under the electric pulse condition, first-time solid solution heat treatment, acid pickling, cold rolling annealing and finished product heat treatment are sequentially carried out, and the solid solution strengthening type difficult-to-deform nickel-based high-temperature alloy strip is obtained.

The invention relates to the technical field of bearing manufacturing, and provides a high-strength and high-toughness double-peak tempering heat treatment method for aero-engine high-nitrogen bearing steel, which comprises the following steps: a steel ingot of the high-nitrogen bearing steel is subjected to cold rolling after being forged and annealed, the rolling speed is less than 10m / min, and the rolling deformation is 30-40%; after a rolled workpiece is austenitized, the workpiece is sequentially subjected to first-time deep cooling (-196 DEG C to-80 DEG C), pre-strengthening tempering (160-180 DEG C), second-time deep cooling (-196 DEG C to-80 DEG C) and final strengthening tempering (450-500 DEG C), and the high-strength and high-toughness aero-engine high-nitrogen bearing steel is obtained. According to the high-strength, high-toughness and high-corrosion-resistance forming and manufacturing method, the high-strength, high-toughness and high-corrosion-resistance requirements of a bearing under the extreme working condition of an aero-engine are met, the tempering technology of'double-peak tempering 'formed by cold rolling forming in advance, pre-strengthening tempering and final strengthening tempering is organically combined, a double-strength structure of solution strengthening and precipitation strengthening is obtained, and the high-strength, high-toughness and high-corrosion-resistance forming and manufacturing method is achieved.

The present invention belongs to the technical field of alloys. Disclosed are a nickel-based high-temperature alloy with low cracking sensitivity coefficients, a manufacturing method therefor and the use thereof. The nickel-based high-temperature alloy comprises: 16.73-17.40% of Cr, 15.60-16.70% of Co, 0.00-0.01% of Mo, 5.90-6.30% of W, 1.80-2.12% of Ta, 1.40-1.62% of Nb, 1.90-2.10% of Al, 3.40-3.60% of Ti, 0.12-0.14% of C, 0.003-0.007% of B, 0.005-0.009% of Zr and the balance of Ni and inevitable impurity elements. The present invention obtains the nickel-based high-temperature alloy with low cracking sensitivity coefficients, high aluminum and titanium content, high Co+W solid solution strengthening element content and low oxygen content, and turbine blades made from the alloy by means of the additive manufacturing process exhibit high density, high creep strength and low oxygen content, thereby effectively meeting the technical requirements of high-power gas turbines.

The invention discloses a high-toughness double-phase titanium-nitrogen alloy which comprises the following chemical components in percentage by mass: 0.005% < = C < = 0.01%, 0.008% < = H < = 0.015%, 0.1% < = O < = 0.15%, 0.4% < = N < = 0.6% and the balance of Ti and inevitable impurities. According to the high-toughness double-phase titanium-nitrogen alloy, a certain amount of nanometer FCC phases are induced to be formed by means of interstitial nitrogen solid solution elements, the nanometer FCC phases and an HCP matrix have a coherent relationship, the Ti-N alloy can be effectively strengthened through an HCP-FCC double-phase structure, and excellent plasticity is kept. The high-toughness double-phase titanium-nitrogen alloy is excellent in mechanical property and does not depend on solid solution strengthening, second-phase dispersion strengthening or work hardening ways of expensive rare metals such as V, Mo and Nb, and green low-carbon low-cost preparation of titanium alloy is facilitated.

The present application relates to the manufacture of high-strength steel coated plate welded parts, in particular to a welding material, a high-strength steel workpiece, a laser welded joint and a manufacturing method thereof. The composition of the welding material satisfies the following conditions in terms of percentage by weight: C is greater than or equal to 0.5%, trace alloying elements are 0-0.36%, the content of Mn and Si is less than or equal to 2%, 6% is greater than or equal to 5C+Mn and is greater than or equal to 2.5%, and the rest is Fe and inevitable other elements; the trace alloying elements are at least one of Nb, V and Ti elements, and the content of Nb, V and Ti elements is less than or equal to 0.12%. The method does not need to remove the aluminum coating, utilizes the solid solution strengthening effect of C, and makes the volume fraction of lath martensite in the final weld after quenching greater than or equal to 90%. This scheme reduces the addition of alloying elements, reduces the cost and process control difficulty, avoids the formation of coarse carbides, improves the mechanical properties and stability of the joint, has high fracture strength and elongation, and realizes the double improvement of the strength and toughness and economy of the joint.

The invention provides a high-entropy reinforced gold-based coating as well as a preparation method and application thereof, and relates to the technical field of conductive lubricating materials. The invention provides a high-entropy strengthened gold-based coating. The high-entropy strengthened gold-based coating comprises a Ni transition layer and an Au-FeCoNiCr composite layer, wherein the Ni transition layer and the Au-FeCoNiCr composite layer are sequentially arranged on a copper alloy base material in a stacked mode. The face-centered cubic FeCoNiCr high-entropy alloy formed by Fe, Co, Ni and Cr elements which are obvious in solid solution strengthening of the Au coating and similar in relative atomic mass serves as a doping phase of the gold-based conductive lubricating coating, the grain refinement effect of the coating can be effectively improved, meanwhile, a solid solution structure is formed, and the strength of the coating is enhanced; and moreover, by doping FeCoNiCr, the residual stress of the coating is reduced, the nano hardness and binding force of the coating are improved, and the frictional wear performance of the coating is improved. The high-entropy strengthened gold-based coating provided by the invention has high conductivity and high lubricating property, and is low in cost.

The invention discloses high-strength non-oriented silicon steel with yield strength of 930 MPa and a production method thereof. The non-oriented silicon steel comprises the following chemical components: 3.0 < = Si < = 4.0%, 0.1 < = Al < = 1.2%, 0.1 < = Mn < = 1.0%, 0.0005 < = Nb < = 0.0010%, 0.0018% < = Ti < = 0.0030%, 0.0010% < = V < = 0.0025%, 0.0020% < = C < = 0.0035%, 0.0010% < = N < = 0.0025%, 4.0 < = Si + Al + Mn < = 5.4%, 0.0045% < = Nb + Ti + V < = 0.0055%, and 0.0035% < = C + N < = 0.0050%. According to the production method of the non-oriented silicon steel, the process route of converter smelting, RH refining, continuous casting, hot rolling, acid pickling, cold rolling, annealing and coating is adopted, the heating temperature is larger than or equal to 1200 DEG C and smaller than or equal to 1250 DEG C, the heating time is larger than or equal to 6 h and smaller than or equal to 8 h, the finish rolling temperature is larger than or equal to 750 DEG C and smaller than or equal to 800 DEG C, the coiling temperature is larger than or equal to 700 DEG C and smaller than or equal to 750 DEG C, the annealing target temperature t is-56.8 A2 + 572.9 A-825.7, the annealing actual temperature T is t + / -30, the annealing target speed c is 120 + 1.5 (T-t), and the annealing actual speed C is c + / -5. Three strengthening modes of dislocation strengthening, solution strengthening and precipitation strengthening are comprehensively used, a component-annealing temperature-annealing speed matching relation and a hot rolling process of'high-temperature long-time heating, low-temperature finish rolling and high-temperature coiling 'are designed, the yield strength Rp0.2 of the obtained non-oriented silicon steel is larger than or equal to 930 MPa, the iron loss P1.0 / 400 is smaller than or equal to 57 W / kg, and the magnetic polarization strength J5000 is larger than or equal to 1.52 T.

The invention belongs to the field of repair of high-temperature alloy hot-end components, and particularly relates to a high-strength fusion welding repair method for a difficult-to-weld gas turbine hot-end component. The method comprises the following steps: (1) removing defects of the hot end component of the gas turbine; (2) degreasing the repairing area; (3) carrying out fusion welding repair on the defects by adopting a body welding wire; (4) a surfacing sheath is prepared on the outer surface of the repaired area through solution-strengthened nickel-based alloy welding filler; (5) carrying out hot isostatic pressing treatment on the hot end component; (6) machining and coping a repair area of the hot end component; (7) carrying out nondestructive flaw detection on a hot end component repair area; (8) carrying out standard heat treatment on the hot-end component; and (9) carrying out nondestructive inspection on the hot-end component. The method is used for fusion welding repair of casting defects of the high-temperature alloy hot-end component with high Al + Ti content and difficult to weld and service damage generated after service of the blade, and crack-free high-strength fusion welding repair of the gas turbine hot-end component with poor weldability can be achieved.

The invention relates to the field of high-temperature alloy component design, in particular to a high-temperature alloy compensation design method based on interaction characteristics of an impurity element S and precious metal Ru. The single-crystal high-temperature alloy is prepared through directional solidification, the total content of refractory elements (Cr, W, Mo, Re, Ta, Hf and the like) of the high-temperature alloy exceeds 20 wt.%, the alloy does not contain rare precious metal Ru and the like, the high-temperature creep resistance of the alloy is improved through the solid solution strengthening and precipitation strengthening effects, the content of S in the alloy is smaller than 1 ppm, the TCP phase precipitation tendency is obviously reduced, and the number of TCP precipitated through thermal exposure is minimum. Based on the interaction characteristic of S and Ru, Ru capable of improving the alloy structure stability in the high-generation single-crystal high-temperature alloy is removed, the alloy is compensated and designed by controlling the content of S in the alloy to be smaller than 1 ppm, so that the structure stability of the single-crystal high-temperature alloy is improved, and a guiding thought can be provided for component design of the low-cost high-generation single-crystal high-temperature alloy.

The invention relates to manufacturing of high-strength steel coated and plated plate welding parts, in particular to a welding flux, a high-strength steel workpiece, a laser welding joint and a manufacturing method of the laser welding joint. The solder comprises the following components in percentage by weight: more than or equal to 0.5% of C, 0-0.36% of trace alloy elements, less than or equal to 2% of Mn, less than or equal to 2% of Si, more than or equal to 6% of 5C + Mn and more than or equal to 2.5% of Fe and other inevitable elements, the trace alloy element is at least one of Nb, V and Ti elements, and the content of the Nb, V and Ti elements is not more than 0.12%. According to the method, an aluminum coating does not need to be removed, and the volume fraction of lath martensite in the quenched final weld joint is larger than or equal to 90% by means of the solid solution strengthening effect of C. According to the scheme, alloy element addition is reduced, cost and process control difficulty are lowered, thick carbide is prevented from being formed, the mechanical property and stability of a joint are improved, and the high breaking strength and ductility are achieved; the obdurability and the economical efficiency of the joint are improved.

The invention relates to the technical field of wear-resistant steel ball casting, and discloses a process for producing as-cast wear-resistant steel balls by using a multi-element modified alloy, which comprises the following steps of: smelting molten steel, namely putting raw materials into an electric arc furnace or an induction furnace, heating to 1550-1650 DEG C, and smelting to obtain basic molten steel; multi-element modified alloy is added, specifically, the multi-element modified alloy is added into the smelted molten steel, the adding amount of the multi-element modified alloy accounts for 0.5%-2.0% of the total weight of the molten steel, stirring is conducted for 10-30 minutes at the temperature of 1500-1600 DEG C, and the alloy is made to be evenly dispersed; performing modification treatment; according to the multi-element modified alloy, through the synergistic effect of the rare earth element RE and the alkaline metal components Ba and Ca, deep deoxidation and impurity purification are achieved in the molten steel smelting stage, the oxygen activity is reduced, non-metallic inclusion residues are reduced, meanwhile, the grain structure is refined through a solid solution strengthening mechanism of MnN and CrN, a uniform and compact matrix structure is formed, and therefore the corrosion resistance of the alloy is improved. And the overall compactness and impact toughness of the wear-resistant steel ball are improved.

The invention discloses an in-situ composite titanium carbide reinforced titanium-based alloy and a preparation method thereof. The in-situ composite titanium carbide reinforced titanium-based alloy comprises the following chemical components in percentage by mass: 0 < = N < = 0.010%, 0 < = H < = 0.015%, 0 < = O < = 0.2%, 0.10-0.40% of C and the balance of Ti and inevitable impurities. The preparation method comprises the following steps: mixing the titanium powder and the graphite powder, and carrying out metal laser powder bed fusion printing. According to the invention, through in-situ synthesis of nano TiC particles, the size and morphology of the TiC particles are regulated and controlled, so that the mechanical property of the titanium-based alloy is greatly improved. The titanium-based alloy with high strength and excellent elongation is obtained by using a trace interstitial element C, and is independent of solid solution strengthening, second-phase dispersion strengthening or work hardening ways of expensive rare metals such as V, Mo, Nb and the like, so that green and low-cost preparation of the titanium alloy is facilitated.

The invention relates to an aluminum alloy welding material and a high-toughness welding seam preparation method, and belongs to the technical field of welding. According to the aluminum alloy welding material, cold metal transition, pulse hybrid welding, laser welding and other welding technologies are combined for rapid cooling, so that Mg, Cu, Zn and other elements in a weld joint are subjected to complete solid solution and are in a supersaturated state, and the joint strength mainly comes from solid solution strengthening contribution of Mg, Cu, Zn and other alloy elements and precipitation strengthening contribution of a corresponding strengthening phase; and then a solute-vacancy coupling diffusion mechanism can be achieved through short-time natural aging, a high-density strengthening phase is rapidly separated out from the welding seam, and therefore the welding seam is strengthened and toughened, and the welding seam strength and the welding coefficient are remarkably improved. Therefore, manual aging intervention is avoided, the welding cost is reduced, and the welding efficiency is improved.

The invention relates to a 1400 MPa-grade high-cobalt low-tungsten nickel-based alloy for a second-generation high-temperature superconducting baseband and a preparation method of the 1400 MPa-grade high-cobalt low-tungsten nickel-based alloy, and belongs to the technical field of materials. On the basis of the Hastelloy alloy, the Co element with the optimized content is added, solid solution strengthening and TCP phase precipitation restraining are achieved, and the high plasticity of the nickel-based alloy is guaranteed; by increasing the content of Cr, the oxidation resistance of the material is ensured; and the Mo content is reduced, Mo and W elements are promoted to completely enter a matrix in a solid solution mode, no TCP phase precipitation is achieved in the hot rolling process, cracking caused by a residual second phase in the subsequent cold rolling process is avoided, and therefore the preparation technological process of the material is simplified, and the material manufacturing cost is reduced. By adopting the component control strategy, the simplified preparation technology and the heat treatment technology, the nickel-based alloy with the tensile strength being 1400 MPa or above and the elongation being larger than 21.0% can be obtained after annealing is conducted for 5 min at the temperature of 900 DEG C, and the requirement of a second-generation high-temperature superconducting high-performance metal base band is met.

The invention discloses round steel for a phi 300mm large-specification petroleum valve body and a production method of the round steel. The round steel comprises the following chemical components in percentage by weight: 0.17%-0.20% of C, 0.20%-0.30% of Si, 1.23%-1.35% of Mn, 0.015%-0.030% of Al, 0.005%-0.015% of V and the balance of iron and inevitable impurities. On the basis of solution strengthening of C and Mn, V, Al and other fine-grain alloy elements are designed and added, dispersed precipitation of carbon and nitride fine particles and solution strengthening of the V and Al elements are achieved through controlled rolling to refine grains, the strength and toughness of the round steel are greatly improved, it is guaranteed that the grains are fine, and the normalized V-type-50 DEG C low-temperature impact of the round steel is larger than 100 J; and the grain size in the hot rolling state is 6.5-7.0 grade, and the requirements of downstream customers can be completely met.

The invention discloses high-endurance-strength high-silicon martensite heat-resistant steel for a lead-bismuth reactor and a preparation method of the high-endurance-strength high-silicon martensite heat-resistant steel, and belongs to the technical field of corrosion-resistant and heat- The heat-resistant steel comprises C, Si, Cr, Ni, Mo, W, Mn, V, Nb and N, the Mo equivalent is 0.8-1.2, the CNB is smaller than 14, and the balance is Fe and inevitable impurities. The formation of a compact SiO2 protective film is promoted by increasing the content of Si, and meanwhile, Mo and W are adopted for synergistic solution strengthening and are matched with N, V and Nb to form a dispersed MX precipitated phase. The heat-resistant steel is prepared through the processes of smelting, homogenizing, forging, hot rolling, normalizing and tempering, and a full-martensite structure can be obtained. And the obtained material has good liquid lead and bismuth corrosion resistance, room-temperature and high-temperature mechanical properties and relatively high high-temperature endurance strength, and is suitable for structural materials serving in high-temperature liquid lead and bismuth environments such as a lead-cooled fast reactor and the like.