Interesting facts about Molybdenum in steel

Mo is usually alloyed together with other elements. Reducing the critical cooling rate improves hardenability. Mo significantly reduces temper brittleness, for example in the case of CrNi and Mn steels, promotes fine grain formation and also favourably affects weldability. Increase in yield point and strength. With increased Mo content, forgeability is reduced. Pronounced carbide former; cutting properties with high speed steel are improved thereby. It belongs to the elements which increase corrosion resistance and is therefore used frequently with high alloy Cr steels and with austenitic CrNi steels. High Mo contents reduce susceptibility to pitting. Very severe restriction of the γ-phase. Increased high temperature strength, scaling resistance is reduced.