01-17-2018, 07:28 AM
In the case of steels, yes the densities are very close and the weight fraction is approximately the same as the volume fraction. Volume fraction is used when actual measurements are made from micrographs, and estimates from the Fe-C diagram are expressed the same. For other systems, one has to be more careful. When digging into bronzes a while ago, l didn't get deep enough to get into this. It's discussed more more for steels, add carbide volume is closely tied to wear resistance and toughness.