PURPOSE: To obtain an electrode excelling in erosion resistance and not causing welding crack, by containing a specified quantity of Co in an 18-8 stainless steel electrode, and maintaining the Cr equivalent in a specified range.
CONSTITUTION: Co is added by 4W8wt% to an 18-8 stainless steel electrode containing Ni>7wt% and Cr>16wt%. In this case, the value of Cr equivalent calculated in wt% Cr+wt% Mo+1.5×wt% Si is controlled within the range of 17W22. The structure should be mixed structure of austenite and ferrite, or austenite and ferrite and martensite, and the area percentage of ferrite is kept within 10W20%. Addition of Co and work hardenability of austenite contributes to the erosion prevention effectively, and the area percentage control of ferrite within 10W20% will prevent occurrence of welding crack.
KIRIHARA SEISHIN
NAKANE KAZUNORI
USAMI KENICHI
