| 摘要 |
PURPOSE:To obtain a seamless sintered steel pipe having excellent stress corrosion cracking resistance, etc. by mixing desired steel kinds of stainless steel powders, packing the powder mixture into a metallic vessel and subjecting the mixture to pressure molding and sintering then to extrusion working, etc. CONSTITUTION:>=1 kinds of powders of ferritic stainless steel powder, austenitic stainless steel, two-phase stainless steel or three-phase stainless steel mixed with martensite therewith are mixed and the mixture composed thereof is packed into the metallic vessel. The inside of the vessel is degassed and gaseous nitrogen is preferably introduced therein. The vessel packed with such mixture is subjected to pressure molding by a hot hydrostatic method, etc. by which the stainless steel powders in the vessel are joined and sintered. The sintered body is subjected to hot extrusion, hot drawing, hot forging, hot rolling, cold extrusion, etc. to form the seamless sintered steel pipe. The SCC resistance is improved and the seamless stainless steel pipe having excellent toughness is obtd. by the above-mentioned method.
|
