Ductile irons containing additions of up to 0·44% Vand 0·48%Co have been prepared and tested in the as cast state and after aferritising heat treatment. In the heat treated condition the microstructure of the alloyed irons consists of graphite nodules in aferrite matrix that contains afine dispersion (20–80 nm in dia.) of V4C3 particles. These carbide particles produce dispersion strengthening and refine the grain size of the ferrite, resulting in an iron of intermediate strength and high ductility.
MST/3079
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