A process in which steel or iron objects are coated with another metal by immersing them in a powder of the second metal and heating to a temperature below the melting point of any of the metals involved. Zinc, chromium, aluminum, copper, and other metals are applied to iron or steel in this fashion. The process is basically diffusion of one metal into the other so that intermetallic alloy layers are formed at the interface of the basis and coating metals.See Sherardizing.