Effects of Niobium and Titanium on the as-cast microstructure of Cr8Mo2VSi cold work die Steel

摘要

In this work, effects of Nb and Ti on the as-cast microstructure of Cr8Mo2VSi cold work die steel are investigated. It is found that the addition of Nb and Ti can effectively refine the dendrites of the steel to equiaxed grains. At the same time, the amount of Cr carbides has been reduced and the morphology of Cr carbides has been improved accompanied with the presence of multi-carbides containing a great amount of Nb, Ti and Mo. In addition, the phosphorous in the steel is moved from the grain boundaries into the multi-carbides.