US Patent 7754142 Acid resistant austenitic alloy for valve seat inserts

A high-carbon austenitic iron-base alloy with good corrosion and wear resistance, particularly useful for valve seat insert applications when corrosion resistance is required, comprises about 1.8-3.5 wt % carbon, about 12-24 wt % chromium, about 0.5-4 wt % silicon, about 12-25 wt % nickel, about 2-12 wt % molybdenum and tungsten combined, about 0.05-4 wt % niobium and vanadium combined, about 0-1 wt % titanium, about 0.01-0.2 wt % aluminum, about 0.05-3 wt % copper, and less than 1.5 wt % manganese, with the balance being iron and a small amount of impurities.