85results about How to "Improve precipitation strengthening effect" patented technology

An ultrathin hot-rolled sheet strip with yield strength more than or equal to 500MPa level comprises the chemical components by weight: 0.02-007%of C, less than or equal to 0.50% of Si, 0.50-1.40% of Mn, less than or equal to 0.030% of P, less than or equal to 0.010% of S, 0.03-0.11% of Ti, 0.01-0.20% of Als, less than or equal to 0.005% of N, less than or equal to 0.004% of O, or 0.17-0.20% of C, less than or equal to 0.50% of Si, 0.50-0.90% of Mn, less than or equal to 0.030% of P, less than or equal to 0.010% of S, 0.03-0.08% of Ti, 0.01-0.20% of Als, less than or equal to 0.005% of N, less than or equal to 0.004% of O. The process comprises melted iron desulfuration, converter blowing, argon blowing, LF furnace refining, continuous casting, rotary descaling, soaking pit soaking, descaling, seven-frame finish rolling, stream cooling and coiling. The ultrathin hot-rolled sheet strip has the advantages that the addition of the alloying element is low, the mechanical property is as follows: the yield strength is more than or equal to 500MPa, the product thickness is less than or equal to 1.4mm, the sheet shape is good, the production flow is short, and excellent cold forming and welding performances are achieved.

The invention relates to low-density ultrahigh-strength steel and a preparation method thereof, and belongs to the field of metal materials. The steel comprises the following chemical components in percentage by mass: 0.6 to 1.6 percent of C, 5 to 10 percent of Al, 15 to 30 percent of Mn, 0.01 to 0.2 percent of Nb, 0.1 to 3 percent of Mo, less than or equal to 5 percent of Cr, less than or equal to 0.5 percent of Ti, less than or equal to 2 percent of Si, less than or equal to 0.6 percent of B, and the balance of Fe and unavoidable impurity elements. According to the low-density ultrahigh-strength steel and the preparation method thereof, a NbMoC phase which is finely dispersed precipitates by compounding and adding the Nb and the Mo; precipitation is strengthened by cooperating with a kappa-carbide; the tensile strength reaches over 1,350 MPa, the elongation reaches over 10 percent and the density is 6.8 to 7.0 g/cm<3>; the low-density ultrahigh-strength steel is low in cost, is suitable for light weight of traffic transportation tools, such as vehicles and airplanes, and meets the development concept of energy conservation and emission reduction.

The invention discloses high-strength wrought magnesium alloy and a preparation method thereof and belongs to the technical field of light metal materials. The high-strength wrought magnesium alloy comprises the following components in percentage by weight: 2.0-6.5% of Zn, 0.1-3.0% of RE, 0.1-2.0% of Ca and the balance of Mg and inevitable impurities; the high-strength wrought magnesium alloy also can comprise grain refiners Mn and/or Zr. Zn is a main strengthening element in the alloy, and can improve the room temperature strength of magnesium alloy through solid solution strengthening and aging precipitation strengthening; Ca is used for promoting precipitation, refining grains and improving high-temperature strength of alloy; and a small amount of RE is used for restraining recrystallization, refining deformed alloy grains, regulating texture and improving plasticity of alloy. According to the invention, by replacing expensive rare earth elements with cheap common alloying elements, a strengthening effect similar to that of rare earth is generated, the rare earth content is completely replaced or lowered and the cost of alloy is reduced while strength is guaranteed.

The invention discloses a 400MPa-level vanadium-containing anti-seismic anti-corrosion rebar and a production method thereof. The rebar is prepared from, by weight, 0.10-0.21% of C, 0.30-0.80% of Si, 1.0-1.60% of Mn, 0.6-1.0% of Cr, 0.05-0.40% of Cu, 0.020-0.10% of V, and the balance Fe and unavoidable impurities, the amount of P is smaller than or equal to 0.030%, and the amount of S is smaller than or equal to 0.030%. The production method includes converter or electric furnace smelting, steel ladle microalloying, external refining, continuous casting, casting blank heating, rolling and cooling bed air cooling. The corrosion resistance of the rebar is improved by controlling the content of Cr and Cu in steel, technological parameters are controlled strictly, the V(C,N) precipitation strengthening effect is promoted under the condition of ensuring steel-plastic tenacity, and the 400MPa-level vanadium-containing anti-seismic anti-corrosion rebar excellent in performance is obtained.

The invention discloses high-strength and high-yield-ratio non-quenched and tempered steel for an automobile engine stretch-broken connecting rod and a production method thereof. The steel comprises the following chemical components in percentage by weight, 0.40-0.50% of C, 0.40-0.60% of Si, 1.00-1.30% of Mn, 0.040-0.060% of S, 0.10-0.20% of V, 0.020-0.035% of Nb, 0.10-0.30% of Cr, 0.10-0.30% of Ni, 0.010-0.020% of N, and the balance Fe and impurity elements. Through the combination of the group distribution ratio and a controlled rolling and controlled cooling process, the mechanical propertyRel of the connecting rod material is greater than or equal to 850 MPa, the Rm is greater than or equal to 1000 MPa, and the yield ratio can reach more than 0.84, so that the light weight of an automobile engine is facilitated.

The invention provides small-scale finish-rolled twisted steel and a production method thereof. The small-scale finish-rolled twisted steel comprises the following chemical components in percentage by mass: 0.40-0.50% of C, 1.5-1.8% of Si, 0.8-1.0% of Mn, less than or equal to 0.035% of P, less than or equal to 0.035% of S, 0.08-0.13% of V, 0.008-0.01% of Als and the balance of Fe and inevitable impurities. The production method comprises the following steps: desulfurizing molten iron, smelting in a converter, blowing argon, performing protective casting into a square blank of 200*200mm<2>, heating the square blank, rolling, performing controlled cooling after rolling, and performing air-cooling in a cooling bed. The finish-rolled twisted steel provided by the invention is stable in property, and the production method is simple and easy to operate.

The invention discloses high-strength and high-toughness cast magnesium alloy. The high-strength and high-toughness cast magnesium alloy is Mg-Bi-Ca-Zn alloy and composed of, by weight, 3.0-8.0% of Bi, 0.1-1.2% of Ca, 0.1-2.0% of Zn and the balance Mg. According to the invention, Bi serves as the main alloy element, lots of Mg3Bi2 phases are formed through the simple alloying way, few Ca elements and Zn elements are adopted for improving the strength of the alloy, the Ca elements effectively improve the morphology and distribution of the Mg3Bi2 phases so as to improve the plasticity of the alloy, and therefore the high-strength and high-toughness cast magnesium alloy can be developed for the Mg-Bi alloy series. The cast magnesium alloy is high in strength and plasticity, the tensile strength of the alloy with the components optimized reaches about 270 MPa, the yield strength of the alloy reaches about 145 MPa, and the ductility of the alloy reaches about 10%. Thus, the strength can be as high as that of rare earth magnesium alloy, and the ductility is high.

The invention relates to hot-rolled round steel and a preparation method thereof. After a steel billet is austenitized and heated, assembly line type rolling is carried out in four steps that descaling and first-time temperature holding are carried out; reciprocating cogging is carried out to obtain an intermediate square billet; head cutting and temperature holding before continuous rolling are carried out, specifically, the intermediate square billet is subjected to head cutting before entering a continuous mill, and secondary air cooling temperature holding is carried out, so that deformedaustenite grains are fully recrystallized, and meanwhile, carbonitrides of Nb and V are fully precipitated; continuous rolling and water passing after rolling are carried out, specifically, the intermediate square billet is rolled into a round steel bar, and the finish rolling temperature of the round steel is controlled to be higher than A<r>3; and the rolled round steel is taken out of the continuous mill and then cooled by passing through water, the structure enters a pseudo-pearlite area from an austenite non-recrystallization area, and the round steel rapidly passes through a ferrite precipitation interval to obtain as many fine lamellar pearlite structures as possible. In the round steel sawing process, due to phase change latent heat and core temperature return of the round steel, surface temperature returns to promote the carbonitrides of the Nb and the V which are not precipitated in time to be precipitated, and carbonitride grains precipitated in the low-temperature intervalare finer.

The present invention relates to an annular joint and a processing method, and belongs to the technical field of material processing. The annular joint is machined from improved 20# steel, the improved 20# steel comprises the following chemical components by mass: 0.17%-0.23% of C; 0.17 %-0.35% of Si; 0.55%-0.75% of Mn; 0.03%-0.06% of Ni; 0.05%-0.20% of Cu; 0.005%-0.008% of Ti; 0.005%-0.01% of Nb; less than or equal to 0.20% of Cr; less than or equal to 0.025% of S; less than or equal to 0.025% of P; and the balance of Fe. The present invention also discloses a processing method of the annular joint, the improved 20# steel is first annular joint forged for forming an annular joint forge piece, the annular joint forge piece is thermally treated, the thermally treated annular joint forge piece is processed into an annular joint semi-finished product by a conventional mechanical roughing method, and an annular joint product is obtained by surface degreasing, pickling for rust removal, electroplating of zinc-nickel alloy, passivation and drying of the annular joint semi-finished product. The strength and corrosion resistance of the annular joint can be significantly increased, and the service life can be significantly prolonged.

The invention discloses protective steel and a production method thereof. The protective steel is prepared from the following components in percentage by mass: 0.10-0.20% of C, 0.10-0.60% of Si, 0.8-1.65% of Mn, 0.02-0.05% of Nb, 0.3-0.8% of Mo, 0.05-0.15% of V, 0.01-0.05% of Ti, 0.01-0.06% of Al, 0.4-1.0% of Cr, 0.0015-0.0025% of B, no more than 0.02% of P, no more than 0.01% of S, no more than 0.008% of N, and the balance of Fe and unavoidable impurities. The problems that in the prior art, high-content C and high-content Mn are added into protective steel, Pcm is designed to be excessivelyhigh, consequently welding performance is lowered, and welding cold cracks and weld joint fatigue cracking are caused are solved, the technical problems of poor cold forming performance and poor low-temperature impact toughness are solved, and the technical effects that the protective steel has good cold forming performance and good low-temperature impact toughness, and safety performance of protected products is improved are achieved.

The invention discloses an extra-thick steel plate resistant to low temperature and lamellar tearing and a manufacturing method thereof. The chemical composition in steel is by weight percentage: C: 0.09% ~ 0.15%, Si: 0.15% ~ 0.45%, Mn: 1.05% ~ 1.45%, S≤0.003%, P≤0.010%, V: 0.06% ~ 0.08% , Als: 0.015% ~ 0.040%, N: 0.008% ~ 0.015%, Ni: 0.25% ~ 0.45%, the steel also contains one or one of Cr≤0.15%, Cu≤0.15%, Ti≤0.04% The above elements, the balance being Fe and unavoidable impurities. The production process of the steel plate is: die casting → billet rolling → finished product rolling → controlled cooling → normalizing treatment → weak cooling after being released from the furnace. The 180-250mm thick steel plate produced has excellent low temperature resistance and lamellar tear resistance in welded structures.

The invention discloses Fe-Cr-based ferrite high temperature steel. The components of the steel are composed of main elements including Fe and Cr, alloying elements including Ni, Mn, Si, Ti and Nb, microalloying elements including C and B and inevitable impurities. The high temperature steel comprises, by mass, of 65-75% of Fe, 18-25% of Cr, 1-5% of Ni, 0-2% of Mn, 2-4% of Si, 0.5-3% of Ti, 1-2.5 % of Nb, 0-0.05% of C and 0-0.08% of B, wherein the total mass percentage of Fe and Cr is 85-95%, the total mass percentage of Ni, Mn, Si, Ti and Nb is 7-13%, and the total mass percentage of C and B is 0-0.1%. A high temperature steel matrix in the technical scheme is a Fe-Cr-based ferrite, in the aging procedure, a spherical dispersedly-distributed coherent lattice nanoscale intermetallic compound Ni16M6Si7 (M=Ti, Nb) phase is dissolved out from the matrix to enable the strength of the steel to be obviously improved. The room-temperature tensile strength of the high temperature steel reaches 950 Mpa, and the instantaneous tensile strength under the high temperature of 600 DEG C is 300 Mpa or over.

The invention provides a preparation method for a Cu-Ni-SI-Ma alloy strip. The method comprises the following steps that a copper source, a nickel source, a silicon source and a magnesium source serve as the raw materials and are sequentially subjected to melting, continuous casting, cooling and billet drawing to obtain a Cu-Ni-SI-Ma alloy rod billet; the Cu-Ni-Si-Ma alloy rod billet is directly subjected to continuous extrusion molding to obtain a Cu-Ni-Si-Mg alloy strip billet; and then rolling and ageing treatment are sequentially conducted to obtain the Cu-Ni-Si-Mg alloy strip. Embodiments show that the elongation, under the room temperature, of the Cu-Ni-Si-Mg alloy rod billet prepared through the preparation method is greater than 45%, and excellent plasticity is achieved; and melting and continuous casting in combination of cooling enforcement measures are adopted, continuous casting and fast solidification can be achieved, the solution strengthening and precipitation strengthening effects of alloy elements are effectively improved, and the method for continuous casting, continuous extruding, rolling and efficient molding of the Cu-Ni-Si-Mg alloy strip is provided.

The invention relates to a high-strength and heat-resisting rare earth aluminum alloy containing rare earth samarium and a preparing method of the high-strength and heat-resisting rare earth aluminumalloy and belongs to the technical field of alloys. The aluminum alloy comprises the following components including, by mass percent, 5%-6% of Zn, 2%-3% of Mg, 1%-2% of Cu, 0.1%-0.2% of Sm and the balance Al and inevitable impurities. Various second phases, uniform and fine microstructures and weak base plane textures are evenly distributed in the alloy, and therefore the alloy can have high strength and high plasticity. The invention further discloses a preparing method of the high-strength and heat-resisting rare earth aluminum alloy material, nano-order and micron-order second phases and grains with the size being relatively fine are evenly distributed in the tissue of the prepared aluminum alloy, and the mechanical performance of the aluminum alloy is obviously improved.

The invention discloses a preparation method of a high-strength and high-conductivity copper-silver alloy wire. The alloy mainly comprises 0.2 to 8.0 percent by weight of Ag, not more than 0.1 percentof impurities and the balance of Cu. The preparation method sequentially comprises the steps of vacuum melting, vacuum continuous casting, aging and multi-pass drawing. By means of the technology, the content of solid solution Ag atoms in the alloy can be well controlled, and meanwhile, nano Ag is separated out, so that the dislocation density of the alloy is improved, and the alloy obtains the maximum separation strengthening and dislocation strengthening effects. Compared with a traditional method that solid solution is conducted firstly and then aging is conducted, the preparation method provided by the invention has the advantages that the mechanical property of the Cu-Ag alloy is guaranteed, meanwhile, higher electrical conductivity can be obtained, the mechanical property and the electrical conductivity of the prepared copper-silver alloy wire are well matched, the technological process is shortened, and the production cost is reduced.

The invention discloses hot-dip galvanized low-alloy high-strength steel with yield strength of 700Mpa and a preparation method of the hot-dip galvanized low-alloy high-strength steel. The hot-dip galvanized low-alloy high-strength steel comprises the following chemical components in percentage by weight: 0.07-0.12% of C; 0.2 to 0.5 percent of Si; mn: 1.1 to 1.5%; 0.02% to 0.06% of Nb; 0.06% to 0.12% of Ti; less than or equal to 0.020% of P; s is less than or equal to 0.012%; the content of Als is 0.02 to 0.06 percent; n is less than or equal to 0.006%, and the balance is Fe and inevitable impurities. The preparation method comprises the procedures of smelting, hot rolling, cold rolling and hot galvanizing. Through reasonable design of low-carbon, Nb and Ti microalloying components, hot rolling, cold rolling reduction rate and a hot dipping continuous annealing process are matched, a certain amount of temper mill extension is used, the precipitation strengthening effect of a steel plate is strengthened, and the hot-dip galvanized low-alloy high-strength steel which is uniform in structure, stable in mechanical performance, good in cold bending performance and high in corrosion resistance is obtained.

The invention discloses a high nitrogen-vanadium microalloying large-scale anti-seismic reinforcing steel bar preparation method. In the steelmaking converter steel tapping process and the ladle furnace (LF) refining process, a certain amount of vanadium pig iron is added to replace an expensive vanadium alloy, so that the molten steel V content is increased; and in the steelmaking deoxidation alloying process, a high nitrogen-vanadium alloy and appropriate amount of silicon-nitrogen alloys are added, and molten steel is subjected to LF refining and nitrogen-blowing treatment, so that the nitrogen content in the molten steel is increased, a V/N matching ratio in steel is remarkably reduced, and a steel precipitation strength effect is remarkably improved. According to the high nitrogen-vanadium microalloying large-scale anti-seismic reinforcing steel bar preparation method provided by the invention, through the integrated innovation of chemical composition design, converter smelting, deoxidation alloying, LF refining, continuous casting, a rolled steel heating schedule, rolling temperature and a controlled cooling technology, a produced reinforcing steel bar has the advantages of excellent and stable process mechanical property, fine and uniform microscopic structure, good ductility and toughness, low strain timeliness, excellent anti-seismic property and the like, the production cost is reduced, the anti-seismic property is improved, and the market competitiveness of products is improved.