Patent ID: 7250071

Claim:
A method of manufacturing austenitic stainless steel, which comprises the steps of: preparing a molten steel having the composition comprising approximately 0-0.04 mass % C, approximately 0.1-1.0 mass % Si, approximately 0-5.0 mass % Mn, approximately 0-0.0060 mass % S, approximately 0-0.003 mass % Al, approximately 5-9 mass % Ni, approximately 15-20 mass % Cr, approximately 0-0.035 mass % N, approximately 1.0-5.0 mass % Cu and the balance being Fe except inevitable impurities with provisions of d =1.9Ni+32C+27N+0.15(Mn+Cu)−1.5Cr+8.5≦0 and a =Ni+0.5Cr+0.7(Mn+Cu)−18>0; covering said molten steel with basic slag in a vacuum or non-oxidizing atmosphere; and deoxidizing said molten steel by addition of a Si alloy whose Al content is controlled less than approximately 1.0 mass % so as to disperse MnO—SiO 2 —Al 2 O 3 type nonmetallic inclusion in a solidified steel matrix, wherein the nonmetallic inclusion contains 15 mass % or more SiO 2 and 40 mass % or less Al 2 O 3 .