Abstract
A study has been made to reveal a preferable alloying element for the formation of massive carbides in HIP processed roll steel, pre-mixed with high alloy iron powder, and the mechanism of the formation has been discussed. Five kinds of high alloy gas atomized iron powders (3.5%C+14%Cr, 3%C+30%Mn. 4%C+8%V, 3%C+10%Mo and 3%C+10%W) were mixed with gas atomized adamite steel powder containing 1.7%C-1.2%Cr, respectively, followed by HIP processing to full density. The micro-hardness measurement, the observation of microstructure and EPMA analysis were carried out to examine the extent of carbide formation.
The results showed that high chromium iron powder and high manganese iron powder changed into massive carbides (M3C, M7C3), whose size is almost the same as that of powder particles during HIP processing, whereas high vanadium iron powder, high molybdenum iron powder and high tungsten iron powder do not change into massive carbides, because these elements make those carbides unstable.
