Manufacture of austenitic stainless steel used in atmosphere of high-temperature and high-pressure water

Abstract

Abstract PURPOSE: To increase strength and to improve the resistance to grain boundary stress corrosion cracking, by subjecting an austenitic stainless steel contg. Nb to heat treatment and to hot rolling at a specific temp. CONSTITUTION: An austenitic stainless steel having the following composition is manufactured: <0.2 % C, < 1 % Si, < 2 % Mn, 17W20 % Cr, 7W11 % Ni, < 0.015 % P, < 0.005 % S, 0.025W0.10 % N, ≥0.45 % C+N, 0.20W0.32 % Nb, or in addn., one or two members selected from the group consisting of 0.02W0.06 % REM, 0.002W0.02 % Ca, further contg. ≤ 0.10 % each of Mo, Co which are present in a specific ratio. The steel material is heated to 1,160W1,280°C, hot rolled at a finishing temp. of 750W950°C, and heat-treated at a precipitation heat- treatment temp. of 980W1,050°C. Hereby, strength and grain boundary cracking type stress corrosion cracking resistance are remarkably improves so that steel material suited for use in manufacturing recycling pipe liners for boiling light-water reactors is obtained. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Takashi Okazaki
• 👤 Sakae Noguchi
• 👤 Tadashi Nakayama
• 👤 Tadashi Nishi

Bibliographic Details