Patent application number | Description | Published |
20090196783 | Austenitic stainless steel welded joint and austenitic stainless steel welding material - An austenitic stainless steel welded joint, which comprises by mass %, C: 0.05 to 0.25%, Si: not more than 2%, Mn: 0.01 to 3%, P: 0.05 to 0.5%, S: not more than 0.03%, Cr: 15 to 30%, Ni: 6 to 55%, sol. Al: 0.001 to 0.1% and N: not more than 0.03%, with the balance being Fe and impurities, and satisfies the formula of (Cr+1.5×Si+2×P)/(Ni+0.31×Mn+22×C+14.2×N+5×P)≧1.388, has high creep strength, and moreover, is economical and excellent in weldability. Therefore, the said austenitic stainless steel welded joint can be widely applied as steel pipes, steel plates and so on in such fields where not only high-temperature strength and corrosion resistance but also weldability is required. Each element symbol in the above formula represents the content by mass percent of the element concerned. | 08-06-2009 |
20090285713 | LOW ALLOY STEEL FOR HIGH-PRESSURE HYDROGEN GAS ENVIRONMENT AND CONTAINER FOR HIGH-PRESSURE HYDROGEN - Provided is a low alloy steel for high-pressure hydrogen gas environments, which contains, by mass percent, C: 0.15 to 0.60%, Si: 0.05 to 0.5%, Mn: 0.05 to 3.0%, P: not more than 0.025%, S: not more than 0.010%, Al: 0.005 to 0.10%, Mo: 0.5 to 3.0%, V: 0.05 to 0.30%, O (oxygen): not more than 0.01%, N: not more than 0.03%, and the balance Fe and impurities, and has tensile strength of not less than 900 MPa. This low alloy steel desirably contains B of 0.0003 to 0.003%, but in this case, N is limited to not more than 0.010%. It is desirable to contain at least one among Cr, Nb, Ti, Zr, and Ca. The contents of Mo and V desirably satisfy the following formula (1): | 11-19-2009 |
20090291017 | HIGH STRENGTH Cr-Ni ALLOY MATERIAL AND SEAMLESS PIPE FOR OIL WELL - [Object] To provide a high strength Cr—Ni alloy material excellent in hot workability and stress corrosion cracking resistance, and seamless pipe for oil well. | 11-26-2009 |
20100062279 | Austenitic stainless steel welded joint and austenitic stainless steel welding material - An austenitic stainless steel welded joint, whose base metal and weld metal each comprises, by mass percent, C: not more than 0.3%, Si: not more than 2%, Mn: 0.01 to 3.0%, P: more than 0.04% to not more than 0.3%, S: not more than 0.03%, Cr: 12 to 30%, Ni: 6 to 55%, rare earth metal(s): more than 0.2% to not more than 0.6%, sol. Al: 0.001 to 3% and N: not more than 0.3%, with the balance being Fe and impurities, and satisfies the formula of (Cr+1.5×Si+2×P)/(Ni+0.31×Mn+22×C+14.2×N+5×P)<1.388, in spite of having a high P content and showing the fully austenitic solidification, has excellent resistance to the weld solidification cracking. Therefore, the said austenitic stainless steel welded joint can be widely used in such fields where a welding fabrication is required. Each element symbol in the above formula represents the content by mass percent of the element concerned. | 03-11-2010 |
20100086430 | HEAT RESISTANT FERRITIC STEEL - There is provided a heat resistant ferritic steel, excellent in the weld crack resistance of the HAZ and creep strength. A high-Cr heat resistant ferritic steel is characterized by consisting of, by mass %, Si: more than 0.1% and not more than 1.0%, Mn: 2.0% or less, Co: 1 to 8%, Cr: 7 to 13%, V: 0.05 to 0.4%, Nb: 0.01 to 0.09%, either one or both of Mo and W: 0.5 to 4% as a total, B: 0.005 to 0.025%, Al: 0.03% or less, and N: 0.003 to 0.06%, and containing C in an amount satisfying Expression (1), the balance being Fe and impurities, and O, P and S as impurities being such that O: 0.02% or less, P: 0.03% or less, and S: 0.02% or less, respectively, | 04-08-2010 |
20100170320 | METHOD FOR MANUFACTURING A HIGH ALLOY PIPE - A method for manufacturing a high alloy pipe comprises hot working, a high alloy material pipe having controlled amounts of C, Si, Mn, P, S, Ni, Cr, Mo, Cu, Al, N, O, and optionally Ca, Mg, and rare earth elements, with the balance Fe. The pipe composition satisfies the formula N×O≦0.001. The pipe is subjected to cold working to form the high alloy pipe, wherein the final cold working process is performed under the condition that a working ratio Rd in the reduction of area satisfies 15≦Rd(%)≦370×(C+N), where N, O and C are the contents (by mass percent) of the respective elements, and Rd is the working ratio (%) in the reduction of area. The pipe has an excellent ductility and an excellent corrosion resistance when cold working is performed to obtain a high strength after pipe-making. | 07-08-2010 |
20110064649 | AUSTENITIC STAINLESS STEEL FOR HYDROGEN GAS AND A METHOD FOR ITS MANUFACTURE - An austenitic stainless steel for use in a hydrogen gas atmosphere comprises, in mass %, C: 0.10% or less, Si: 1.0% or less, Mn: 0.01 to 30%, P: 0.040% or less, S: 0.01% or less, Cr: 15 to 30%, Ni: 5.0 to 30%, Al: 0.10% or less, N: 0.001 to 0.30% with the balance Fe and inevitable impurities. An X-ray (111) integration intensity of a cross section along the direction rectangular to the working direction is five times that in a random direction or less, and the X-ray integration intensity ratio of a cross section along the working direction satisfies I(220)/I(111)≦10. The high strength steel can also contain one or more of the groups of Mo and W; V, Nb, Ta, Ti, Zr and Hf; B; Cu and Co; Mg, Ca, La, Ce, Y, Sm, Pr and Nd. | 03-17-2011 |
20110088819 | AUSTENITIC HEAT RESISTANT ALLOY, HEAT RESISTANT PRESSURE MEMBER COMPRISING THE ALLOY, AND METHOD FOR MANUFACTURING THE SAME MEMBER - An austenitic heat resistant alloy, which comprises by mass percent, C: over 0.02 to 0.15%, Si≦2%, Mn≦3%, P≦0.03%, S≦0.01%, Cr: 28 to 38%, Ni: over 40 to 60%, Co≦20% (including 0%), W over 3 to 15%, Ti: 0.05 to 1.0%, Zr: 0.005 to 0.2%, Al: 0.01 to 0.3%, N≦0.02%, and Mo<0.5%, with the balance being Fe and impurities, in which the following formulas (1) to (3) are satisfied has high creep rupture strength and high toughness after a long period of use at a high temperature, and further it is excellent in hot workability. This austenitic heat resistant alloy may contain a specific amount of one or more elements selected from Nb, V, Hf, B, Mg, Ca, Y, La, Ce, Nd, Sc, Ta, Re, Ir, Pd, Pt and Ag. P≦3/{200(Ti+8.5×Zr)} . . . (1), 1.35×Cr≦Ni+Co≦1.85×Cr . . . (2), Al≧1.5×Zr . . . (3). | 04-21-2011 |
20110223055 | Ni-BASE HEAT RESISTANT ALLOY - A Ni-base heat resistant alloy, which comprises by mass percent, C: 0.1% or less, Si: 1% or less, Mn: 1% or less, Cr: not less than 15% to less than 28%, Fe: 15% or less, W: more than 5% to not more than 20%, Al: more than 0.5% to not more than 2%, Ti: more than 0.5% to not more than 2%, Nd: 0.001 to 0.1% and B: 0.0005 to 0.01%, with the balance being Ni and impurities, in which the contents of P, S, Sn, Pb, Sb, Zn and As among the impurities are P: 0.03% or less, S: 0.01% or less, Sn: 0.020% or less, Pb: 0.010% or less, Sb: 0.005% or less, Zn: 0.005% or less and As: 0.005% or less, and further satisfies the formulas of [0.015≦Nd+13.4×B≦0.13], [Sn+Pb≦0.025] and [Sb+Zn+As≦0.010] is an alloy in which much higher strength than the conventional Ni-base heat resistant alloy can be achieved, the ductility and toughness after a long period of use at a high temperature are remarkably improved, and moreover the zero ductility temperature and the hot workability are also further improved. This alloy can be suitably used as a pipe material, a thick plate material for a heat resistant pressure member, a bar material, a forging, and the like for a boiler for power generation, a plant for chemical industry, and the like. This alloy may contain a specific amount of one or more elements selected from Mo, Co, Nb, V, Zr, Hf, Mg, Ca, La, Ce, Ta and Re. | 09-15-2011 |
20120031534 | METHOD FOR PRODUCING HIGH-STRENGTH Cr-Ni ALLOY SEAMLESS PIPE - A method for producing a high-strength Cr—Ni alloy seamless pipe comprising preparing an alloy billet with a chemical composition consisting, by mass %, of C: 0.05% or less, Si: 1.0% or less, Mn: less than 3.0%, P: 0.005% or less, S: 0.005% or less, Cu: 0.01 to 4.0%, Ni: 25% or more and less than 35%, Cr: 20 to 30%, Mo: 0.01% or more and less than 4.0%, N: 0.10 to 0.30%, Al: 0.03 to 0.30%, O (oxygen): 0.01% or less, REM (rare earth metal): 0.01 to 0.20%, and the balance being Fe and impurities, and satisfying the formula N×P/REM≦0.10, wherein P, N and REM represent the contents (mass %) of P, N and REM, respectively. The pipe is hot worked using cross roll piercing, solution heat treated, and cold worked. The pipe is excellent in hot workability, stress corrosion cracking and does not laminate during cross piercing. | 02-09-2012 |
20130263974 | AUSTENITIC HEAT RESISTANT ALLOY, HEAT RESISTANT PRESSURE MEMBER COMPRISING THE ALLOY, AND METHOD FOR MANUFACTURING THE SAME MEMBER - An austenitic heat resistant alloy, which comprises by mass percent, C: over 0.02 to 0.15%, Si≦2%, Mn≦3%, P≦0.03%, S≦0.01%, Cr: 28 to 38%, Ni: over 40 to 60%, Co≦20% (including 0%), W over 3 to 15%, Ti: 0.05 to 1.0%, Zr: 0.005 to 0.2%, Al: 0.01 to 0.3%, N≦0.02%, and Mo<0.5%, with the balance being Fe and impurities, in which the following formulas (1) to (3) are satisfied has high creep rupture strength and high toughness after a long period of use at a high temperature, and further it is excellent in hot workability. This austenitic heat resistant alloy may contain a specific amount of one or more elements selected from Nb, V, Hf, B, Mg, Ca, Y, La, Ce, Nd, Sc, Ta, Re, Ir, Pd, Pt and Ag. | 10-10-2013 |
20130283879 | Ni BASE ALLOY PIPE STOCK AND METHOD FOR MANUFACTURING THE SAME - A method for manufacturing an Ni base alloy pipe stock comprises piercing and rolling a billet by use of Mannesmann piercing and rolling mill. The pipe stock has controlled amounts of C, Si, Mn, P, S, Cr, Ni, Mo, W, Cu, Al, N, with the balance being Fe. With the method, the following equations are satisfied, wherein values of T | 10-31-2013 |