Effect of Modification Powders on Low Alloy Cast Steel

Effects of V-Ti-Zr-Re containing modification powders on the mechanical properties and microstructure of low alloy steel castings by conventional normalizing, hardening and tempering processes and normalizing-free heat treatment were investigated. The results showed that for the as-modified casting, martensite and carbides were the main phases after direct quenching and low-temperature tempering but skipping normalizing. The mechanical properties were almost the same or even higher in impact toughness than the same material but bearing also normalizing treatment. Both samples modified by alloy powders, whether normalizing treated or not, possessed superior mechanical properties to those castings without being modified. The modification technique can be applied in low alloy steel production to eliminate the time and energy consuming normalization process, so that the cheap, energy saving and environment friendly materials are thus expected.