Abstract: In austenitic free-cutting stainless steel containing lead, decrease of hot workability caused by the addition of lead can be dissolved by adding a specific amount of boron. Thus, there is obtained an austenitic free-cutting stainless steel with improved machinability, corrosion resistance and hot workability of which are maintained at the level of conventional austenitic stainless steel.

Abstract: Ferrite-austenite stainless steel castings having an improved erosion-corrosion resistance consist by weight percentage of not more than 0.1% of C, 0.2-3% of Si, not more than 2% of Mn, 2.2-4% of Cu, 3-9% of Ni, 20-30% of Cr, 2-6% of Mo, 0.08-0.25% of N, 0.12-0.3% of Sn, at least one of 0-2% of Nb, 0-1% of Ti, 0-2% of Ta, 0-1% of Zr and 0-1.5% of V and remainder of Fe, and are obtained by solution heat treatment at 1,000.degree.-1,150.degree. C in such a manner that Cr- and Ni-equivalents lie within an area represented by the area ABCD shown in FIG. 1 of the accompanying drawings.