Japan Atomic Energy Research Institute

Susumi Isobe

Tatsuo Kondo

Hajime Nakajima

Masami Shindo

Hirokazu Tsuji

Ryohei Tanaka

Sadao Ohta

Watanabe Rikizo

The improved superalloy that possesses all the characteristics required of the high-temperature structural material of high-temperature gas-cooled reactors (i.e., high-temperature strength, corrosion resistance, good producibility, good hot workability and resistance to embrittlement due to thermal aging) consists essentially of 16-28% Cr, 15-24% W (provided that Cr+W=39-44%), 0.01-0.1% Zr, 0.001-0.015% Y, 0.0005-0.01% B, up to 0.05% C, up to 0.1% Si, up to 0.1% Mn (provided that Si+Mn.ltoreq.0.1%), up to 0.1% Ti, up to 0.1% Al and up to 0.1% Nb (provided that Ti+Al.ltoreq.0.1% and Ti+Al+Nb.ltoreq.0.15%), with the balance being Ni and inevitable impurities and all percentages being on a weight basis.

Nickel-chromium-tungsten base superalloy

Growing community of inventors

Aichi, Japan

Susumi Isobe