ASTM A897/A897M-22

Die Annotation des Normtextes ASTM A897/A897M-22 :

This specification covers ductile iron castings that are subsequently heat treated by an austempering process. The chemical composition requirements may be agreed upon between the manufacturer, heat treater, and the purchaser. Requirements for the microstructure constituents such as graphite, ausferrite (acicular ferrite and high carbon, stable austenite), pearlite, and martensite are prescribed. The iron shall conform to the mechanical property requirements including tensile strength, yield strength, elongation, impact energy, and Brinell hardness. Castings shall be heat treated by an austempering process detailed in this specification. The standard specimens for tension and Charpy impact tests are illustrated.


Keywords:
ausferrite, austempering, ductile cast iron, hardenability, heat treatment, proeutectoid ferrite,, ICS Number Code 77.140.80 (Iron and steel castings)