Noun
a chemical compound that is a constituent of steel and cast iron; very hard and brittle
Source: WordNetVerhoeven and Pendray had already determined that the grains on the surface of the steel were grains of iron carbide—their goal was to reproduce the iron carbide patterns they saw in the Damascus blades from the grains in the wootz. Source: Internet
The wootz was in a soft, annealed state, with a grain structure and beads of pure iron carbide which were the result of its hypereutectoid state. Source: Internet
This iron carbide is very different from the cast iron the rest of the disc is composed of. Source: Internet