Stereological parameters of carbide particles and properties of conventional and nonledeburitic high-speed steels
Abstract
Using new methods of quantitative description of the microstructure, stereological parameters of primary carbides in conventional and nonledeburitic economical tool alloys were compared. It was established that nonledeburitic alloys produced with a technology similar to that of typical high-speed steels, present no carbide macrosegregation and only a slight microsegregation, a considerably smaller carbide shape and size inhomogeneity and also a significantly smaller variability of microstructure on the transverse section of forged bars. These alloys show competitive in service properties to those of typical high-speed steels. The results indicate a fundamental importance of carbides segregation and its effect on tool life. The findings also confirm that large carbides of subcritical size diminish less the properties of tool alloys than fine, close lying carbide particles.