18 results about "Equivalent weight" patented technology

This invention relates to a 1900MPa grade ultra-high strength and toughness stainless gear steel and its preparation method. The chemical composition of the 1900MPa grade ultra-high strength and toughness stainless gear steel, by mass percentage, is: C 0.08-0.11%, Cr 10-12%, Ni 2-4%, Mo 2-5%, Co 10-13%, V 0.2-0.6%, Nb 0.02-0.05%, Al 0.5-1.0%, with the balance being Fe and unavoidable impurities. Its composition design must meet the following requirements: Chromium equivalent Cr... eq It is 17~18, with a nickel equivalent (Ni). eq The martensitic transformation point is 14-15. s The temperature range is 240~280℃. Its beneficial effects are: strengthening through the composite precipitation of intermetallic compounds NiAl and M₂C carbides, combined with Cr... eq Ni eq M s A synergistic design incorporating 5%–10% metastable austenite achieves an excellent balance between strength and toughness. The resulting steel exhibits tensile strength ≥1900 MPa, yield strength ≥1550 MPa, elongation ≥13%, fracture toughness ≥80 MPa·m¹ / ², and bending fatigue limit reaching 920 MPa. It is particularly suitable for manufacturing critical structural components requiring high load-bearing capacity and high reliability, such as aircraft engines, and has broad application prospects.

A steel material according to the present disclosure has a chemical composition containing, in terms of mass%, 0.10-0.40% C, 0.01-0.45% Si, 0.30-0.95% Mn, not more than 0.030% P, not more than 0.025% S, more than 0.50 and up to 1.80% Cr, 0.005-0.100% Al, not more than 0.0250% N, and not more than 0.0050% O with the remainder being Fe and impurities, wherein: the total area ratio of ferrite and pearlite in the microstructure is not less than 95%; an average equivalent circle diameter DN of nitrides having an equivalent circle diameter of not less than 20 nm is not more than 70 nm; and a sample standard deviation SDN of the equivalent circle diameter of the nitrides is not more than 45 nm.

The invention discloses a low-cost alloyed Q460C / D steel plate and a production method thereof. The low-cost alloyed Q460C / D steel plate comprises the following chemical components: 0.06-0.0.08% of C, 0.1-0.3% of Si, 1.50-1.60% of Mn, less than or equal to 0.010% of P, less than or equal to 0.003% of S, 0.025-0.035% of Als, 0.020-0.030% of Nb, 0.008-0.015% of Ti and the balance of Fe and residual elements, Ceq is less than or equal to 0.35, and meanwhile, the carbon equivalent (Ceq = C + Mn / 6 + Si / 24 + Ni / 40 + Cr / 5 + Mo / 4 + V / 14) is controlled. The steel plate is prepared by the following steps: (1) KR molten iron pretreatment: ensuring that S in molten iron is less than or equal to 0.005%, the desulfurization period is less than or equal to 25 minutes, and the desulfurization temperature drop is less than or equal to 25 DEG C; (2) smelting and casting: under the vacuum degree of 67 Pa, the pressure maintaining time is longer than or equal to 20 min, and meanwhile, the molten steel turning effect in the pressure maintaining process is required to be good; the VD off-station temperature is 1570 to 1575 DEG C; (3) heating: the heating temperature of the steel billet is 1180-1230 DEG C, and the heating time is 1 min / mm, and (4) high-temperature recrystallization direct rolling: after rolling is finished, DQ + ACC cooling is adopted, the cooling speed is controlled to be 10-20 DEG C / s, and the water outlet temperature is controlled to be 370-400 DEG C. The steel plate obtained through the method has the advantages in the aspect of cost economy, and the urgency of market requirements is improved.

To provide an Al-Mg-Si based aluminum alloy sheet capable of obtaining excellent surface properties and formability even in the case the temperature rising rate and heating temperature at the time of intermediate annealing are made low.SOLUTION: The Al-Mg-Si-based aluminum alloy sheet contains Si: 0.50 mass% or more and 1.60 mass% or less, Mg: 0.25 mass% or more and 1.00 mass% or less, Fe: 0.05 mass% or more and 0.50 mass% or less, Mn: 0.01 mass% or more and 0.30 mass% or less, and Cu: 0.001 mass% or more and 0.30 mass% or less, with the balance being Al and inevitable impurities. When the Mg content is represented by [Mg] in mass%, [Mg] / [Si] is more than 0.50, the area ratio of Cube orientation is 9% or less, and the number densities of compounds having equivalent circle diameters of 1.5 μm or more are 1000 particles / mm2 or more and 10000 particles / mm2 or less.SELECTED DRAWING: None

Provided is a steel material having excellent SSC resistance. The steel material of the present invention has a chemical composition, in terms of mass%, of C: 0.035% or less, Si: 1.00% or less, Mn: 1.00% or less, P: 0.030% or less, S: 0.0050% or less, sol. Al: 0.005 to 0.100%, N: 0.001 to 0.020%, Ni: 5.00 to 7.50%, Cr: 10.00 to 14.00%, Cu: 0.01% or more and less than 1.50%, Mo: 1.50 to 3.50%, V: 0.01 to 1.00%, Ti: 0.02 to 0.30%, Co: 0.01 to 0.50%, Ca: 0.0003 to 0.0030%, O: 0.0050% or less, W: 0 to 1.50%, Nb: 0 to 0.50%, B: 0 to 0.0050%, Mg: 0 to 0.0050%, rare earth elements (REM): 0 to 0.020%, and the balance being Fe and impurities, and the total of Mn sulfides having a circle equivalent diameter of 1.0 μm or more and Ca sulfides having a circle equivalent diameter of 2.0 μm or more is 0.50 pieces / mm 2 The following.

The stainless steel contains 0.0001 mass % or more and 0.15 mass % or less of C, 0.30 mass % or more and 2.0 mass % or less of Si, 0.1 mass % or more and 15 mass % or less of Mn, 5 mass % or more and 30 mass % or less of Ni, 0.0001 mass % or more and 0.01 mass % or less of S, 16 mass % or more and 25 mass % or less of Cr, 0 mass % or more and 5 mass % or less of Mo, 0 mass % or more and 0.005 mass % or less of Al, 0 mass % or more and 0.0010 mass % or less of Mg, 0.0010 mass % or more and 0.0060 mass % or less of O, and 0.0001 mass % or more and 0.5 mass % or less of N, and at least includes an inclusion with an equivalent circle diameter of 5 μm or more, having the average composition of 5 mass % or more of MnO, 20 mass % or more of Cr2O3+Al2O3, 1 mass % or more of Al2O3, and 5 mass % or less of CaO. The number density of the inclusion having the composition is 0.5 inclusions / mm2 or less.

The application discloses a low-cost thick-gauge 460MPa nickel-free weather-resistant steel and a manufacturing method thereof. The chemical components of the steel are as follows: C: 0.04-0.07%, Si: 0.55-0.75%, Mn: 0.43-0.63%, P: 0.010-0.014%, S: less than or equal to 0.003%, Cu: 0.3-0.5%, Cr: 0.3-0.5%, Ti: 0.020-0.030%, V: 0.020-0.030%, B: 0.0007-0.0013%, Al: 0.020-0.030%, Zr: 0.0009-0.0015%, and the balance of Fe and other inevitable impurities; and the chemical components need to meet the following conditions simultaneously: a welding crack sensitivity index Pcm is less than or equal to 0.17%; a carbon equivalent CEV is less than or equal to 0.32%; a weather resistance index I is greater than or equal to 6.0; Cu / P+5*Si is greater than or equal to 25; and 0.06% is less than or equal to (Al+Ti+V) and is less than or equal to 0.085%. The obtained weather-resistant steel has the characteristics of high strength and weather resistance, good surface quality, low yield ratio and easy welding without adding Ni, the thickness of the steel can reach 60 mm at most, the use range of the high-strength weather-resistant steel is widened, and the weather-resistant steel can be widely used for manufacturing corrosion-resistant structural parts.

The invention discloses low-cost thick-specification 590 MPa nickel-free weathering steel and a manufacturing method thereof. The low-cost thick-specification 590 MPa nickel-free weathering steel comprises the following chemical components in percentage by weight: 0.06 to 0.09 percent of C, 0.65 to 0.85 percent of Si, 0.53 to 0.83 percent of Mn, 0.010 to 0.014 percent of P, less than or equal to 0.003 percent of S, 0.3 to 0.5 percent of Cu, 0.3 to 0.5 percent of Cr, 0.020 to 0.030 percent of Ti, 0.020 to 0.030 percent of V, 0.0015 to 0.0020 percent of B, 0.020 to 0.030 percent of Al, 0.0015 to 0.0020 percent of Zr and the balance of Fe and other inevitable impurities. The chemical components need to simultaneously meet the following requirements: the welding crack sensitive index Pcm is less than or equal to 0.22%; the carbon equivalent CEV is less than or equal to 0.35%; the weather-proof index I is greater than or equal to 6.2; cu / P + 5 * Si > = 25; 0.06% < = (Al + Ti + V) < = 0.085%. According to the weathering steel, the yield strength is larger than or equal to 590 MPa, the tensile strength is larger than or equal to 710 MPa, the impact energy at the temperature of-20 DEG C is 190-360 J, the yield ratio is smaller than or equal to 0.85, and no copper brittleness crack exists on the surface of a steel plate.

The present invention aims to provide a colloidal silica containing silica particles having a proper true specific gravity, a high aggregation ratio, and a high alkoxyl group content at a high purity, and a production method capable of easily producing the colloidal silica and reducing the production cost. The present invention relates to a colloidal silica characterized in that the silica particles contained in the above colloidal silica have an average primary particle diameter of 33 nm or more, an aggregation ratio of 1.2 or more, a true specific gravity of 1.95 or more, contain 1000 mass ppm or more of an alkoxyl group per 1 g of the silica particles, have a proportion of the number of silica particles having a circular equivalent diameter of less than 20 nm of less than 15%, and contain 5 μmol or more of a primary amine per 1 g of the silica particles.

The present invention relates to a composition, preferably for bonding together metal sheets, comprising:a. 1 part by mole of at least one linear epoxy resin with an average epoxy equivalent weight of 600 to 5,000 g / mole and an epoxy functionality of 2,b. 0.4 to 0.8 parts by mole of at least one non-linear epoxy resin having an average epoxy equivalent weight of 180 to 350 g / mole and an average epoxy functionality of at least 3,c. 0.8 to 1.3 parts by mole of at least one basic hardener comprising at least two free amine-bonded hydrogen atoms, andd. 0.9 to 1.2 parts by mole of at least one crosslinker comprising at least two blocked isocyanate groups.

An ultra-high solids content primer coating composition comprising:(i) 5.0 to 50 wt % of at least one bisphenol F epoxy resin;(ii) 1.5 to 12 wt % of at least one silane;(iii) 0 to 20 wt % of at least one hydrocarbon resin;(iv) 0 to 15 wt % of at least one reactive diluent;(v) at least one curing agent;wherein said composition has a solids content of at least 90 wt % according to ASTM D5201-05;wherein said composition has a viscosity of 200 to 800 cps at 23° C. and 50% RH (ASTM D4287);and wherein the ratio between hydrogen equivalents in the curing agent and epoxy equivalents of the coating composition is in the range 50:100 to 120:100.

This invention discloses a high-strength, high-toughness Nb-containing steel and its nano-phase controlled rolling and cooling preparation method, belonging to the field of iron and steel metallurgy and rolling technology. The chemical composition of the steel plate, by mass percentage, is as follows: C: 0.12~0.20%, Si: 0.55~0.65%, Mn: 1.40~1.50%, Nb: 0.030~0.080%, N: 0.0080~0.0110%, Al: 0.020~0.050%, P≤0.030%, S≤0.025%, with the balance being Fe and unavoidable impurities; and the Nb / N mass ratio is controlled at 3.6~10.0, and the carbon equivalent C≤0.45%. The preparation method includes smelting, refining, continuous casting, heating, two-stage controlled rolling, and segmented controlled cooling steps. Through precise Nb / N ratio combined with controlled rolling and controlled cooling processes, nanoscale Nb(C,N) precipitates with a size of 20~80nm are induced, with a volume fraction ≥0.2%. The resulting steel plate has a microstructure of ferrite + bainite, a tensile strength ≥600MPa, a lower yield strength ≥450MPa, an elongation after fracture ≥18%, an impact absorption energy of ≥40J at -20℃, and a crack incidence rate ≤0.3%. This invention achieves a synergistic improvement in high strength, high toughness, and excellent crack resistance.

Provided in the present invention is a one-component structural adhesive including: 47 to 61 weight percent of a first epoxy resin, the first epoxy resin having an epoxide equivalent weight of less than 240 grams per equivalent; 27 to 41 weight percent of a difunctional mercaptan; and 1 to 14 weight percent of a latent catalyst, wherein the total weight of the one-component structural adhesive is taken as 100 weight percent. The one-component structural adhesive according to the technical solution of the present invention can achieve fast curing at low temperatures, and the cured product thereof has high elongation-at-break and adhesion strength.

The application discloses a 200-210mm thick high-strength low-welding-crack-sensitivity A514 steel plate and a production method thereof. The A514 steel plate comprises the following chemical components (unit, wt%): C: 0.10-0.12, Si: 0.10-0.15, Mn: 0.90-1.0, P≤0.010, S≤0.003, Als: 0.020-0.040, Nb: 0.040-0.050, V: 0.18-0.20, Cr: 0.7-0.75, Ni: 2.01-2.3, Cu: 0.22-0.26, Mo: 0.45-0.50, B: 0.002-0.0030, Re: 0.0015-0.0025, and other Fe and residual elements, and the carbon equivalent Ceq≤0.7%. The 1015-1125mm thick steel ingot is adopted to ensure a large compression ratio, the cogging rolling and the secondary heating rolling are adopted to fully break the original cast structure and refine the grains, so that the internal quality of the steel plate reaches the level of a forged piece, and the rolling is used to replace the forging; the twice circulating quenching is adopted to reduce the mechanical property difference of different thickness layers of the steel plate, the differential temperature tempering process is adopted after the quenching to eliminate the residual stress in the quenched steel, the impact toughness and the strength uniformity of the whole plate are improved, and the performance of the A514 heavy steel plate under the low-temperature condition meets the use requirement.

Provided is a steel material having excellent cold forgeability. This steel material has a prescribed component composition and a structure in which the area ratio of martensite is not more than 10.0% and the remainder contains at least bainite, the number density of sulfide-based inclusions having an equivalent circle radius of 1-20 [mu] m is not less than 10.0 / mm2, and the number density of sulfide-based inclusions having an equivalent circle radius of not less than 1 mm is not more than 0.10 / mm2.

Provided is a steel bar or wire rod with which it is possible to obtain excellent heat cracking resistance and excellent machinability. This steel bar or wire rod has a chemical composition described in the description, and Fn1 defined by formula (1) is 1.2-5.0. Furthermore, the number density of sulfides having an equivalent circle diameter of 1 [mu] m or more is less than 660 / mm2 at a position 0.16 R depth from the surface of the steel bar or wire in a longitudinal section parallel to the central axis of the steel bar or wire and including the central axis. Furthermore, the number density of sulfides having an equivalent circle diameter of 1 [mu] m or more at a depth position of 0.65 R in the vertical section is 660 / mm2 or more. Fn1 = Mn / S (1). Here, the content (mass%) of the corresponding element is substituted at each element symbol in the formula.

The present invention relates to an X80 heavy-gauge high-strength high-strain pipeline steel, a UOE welded pipe, and a manufacturing method therefor. In addition to Fe and inevitable impurities, the pipeline steel further comprises the following chemical components in percentage by weight: 0.051-0.09% of C, 0.1-0.4% of Si, 1.5-1.9% of Mn, P ≤ 0.015%, S ≤ 0.002%, Cu ≤ 0.19%, 0.05-0.19% of Ni, 0.11-0.35% of Cr, Mo ≤ 0.13%, 0.02-0.08% of Nb, 0.005-0.035% of Ti, 0.001-0.004% of Ca, 0.010-0.045% of Alt, N ≤ 0.006%, B ≤ 0.0003%, O ≤ 0.005%, and H ≤ 0.0002%, wherein the carbon equivalent CEIIW is 0.41-0.47%, and 0.60% ≤ Ni + 3Cr ≤ 1.10%, each element symbol in the expression being substituted for the mass percentage content of the corresponding element. The UOE welded pipe of the present invention has a wall thickness of 25-40 mm and a caliber of φ 1016 to φ 1422 mm, and has a yield strength of 555-665 MPa, a tensile strength ≥ 625 MPa, a low-temperature impact energy higher than 1600 J at -20ºC, and a full-wall-thickness DWTT shear fracture area percentage greater than 85% at -10ºC, as well as a longitudinal yield strength of 530-640 MPa, a yield ratio ≤0.85, and a uniform elongation ≥7%.