Carbide phase in R18 steel

1. R18 steel contains mainly the Fe3W3C carbide. Small amounts of (Cr3Fe)23C6 and WC may also be present. 2. The carbides are irregularly distributed through the section of the ingots (or rods) and different carbides and in different amounts are present in the central and peripheral parts of the ingots. 3. There is no great difference in the distribution or shape of the carbides. 4. The smelting method and subsequent treatment have no significant effects on the qualitative composition of the carbide phase.