Grain Size and Forgeability of a Titanium Microalloyed Forging Steel

In recent years, microalloying has been advocated as a means for producing direct cooled forging steels. Microalloyed steels benefit from vanadium and niobium additions, but the carbonitrides formed by these elements are not stable at high temperatures. Micro-additions of titanium, which form a fine dispersion of carbonitrides that are stable at high temperature, have been promoted as an approach fox maintaining a fine austenite grain size at high forging temperatures. In this work two microalloyed steels were examined, 1522MoV and 1522MoV with 0.011 titanium addition. The effect of the titanium additions on the grain size and high temperature flow strength were studied. The titanium addition has a significant effect on maintaining a small austenite grain size at temperatures up to 1300°C. High temperature stress-strain data indicate that titanium causes an increased flow strength at 1100°C and 1200°C especially at higher strain rates. At 1000°C the titanium has little effect on the flow strength of this alloy.