Strength at elevated temperature and the austenite type heatproof cast steel where machinability is superior and then becomes the exhaust air part

摘要

PURPOSE: To obtain an austenitic heat resistant cast steel, excellent in strength at high temp. and machinability, and automobile exhaust system parts, such as exhaust manifold and turbine housing, made of this steel. ;CONSTITUTION: This steel is an austenitic heat resistant cast steel which has a composition consisting of, by weight ratio, 0.2-0.6% C, ≥2% Si, ≤2% Mn, 8-20% Ni, 15-30% Cr, 0.2-1% Nb, W and/or Mo by the amounts in the range satisfying the relation in W+Mo/2=1 to 6%, 0.01-0.5% S, and the balance Fe with inevitable impurities or further containing, besides the above, 0.01-0.3% N. This austenitic heat resistant cast steel can be used for automobile exhaust system parts.;COPYRIGHT: (C)1995,JPO