Effect of melting rate on microsegregation and primary MC carbides in M2 high-speed steel during electroslag remelting

Abstract

High-speed steels (HSSs) are widely used in making cutting tools due to their high hardness and good wear resistance even at high temperature. These excellent properties can be attributed to the carbides uniformly distributed in the matrix, such as MC, M 6 C, etc [1,2] . As for W-Mo HSSs, the as-cast structure at room temperature mainly contains M 2 C eutectic carbides and a small number of large-size primary MC carbides (stable phase) directly precipitate from the liquid phase [3] . Among them, M 2 C is a metastable phase, and could totally decompose into smaller MC and M 6 C secondary carbides after a series of processing [4][5][6] . Even though MC carbides have the highest hardness (around 3,000 HV) and contribute high wear resistance [7] , these

Effect of Alloying and Microalloying Elements on Carbides of High-Speed Steel: An Overview

“…The metal element M is predominantly V among them, and it can dissolve a tiny amount of W, Mo, and Cr. Ti, Nb, and Zr are the elements that can also make MC carbides [9,12]. As depicted in Figure 2, M2C is made up of thin lamellae or fibers [10,13].…”