HF, HH, and HK alloys in specification A297 are increasingly used for automotive exhaust component castings, as the automakers demanded higher engine temperatures. It is also desirable to reduce the raw material costs of Fe-Cr-Ni stainless steels for the automotive industry. In recent years, numerous R&DC (C- commercialization) work has been carried out for ferritic stainless steel, especially 18 to 22% Cr, for automotive applications. The chemistry is similar to CB30 in ASTM 743, but with intentionally added carbon for elevated-temperature strength and castability. This material is also similar to 1.4740 found in some of the European standards. The main objective of this work item is to add a 18 to 22% Cr stainless steel to A297, tentatively referred to as grade HB.
KeywordsCast iron--specifications; Class codes (for metals/alloys); Iron-chromium castings--specifications; Steel castings--specifications;
Draft Under Development