martensitic state
21chromium processing — Introduction preparation of the ore for use in various products. Chromium (Cr) is a brilliant, hard, refractory metal that melts at 1,857° C (3,375° F) and boils at 2,672° C (4,842° F). In the pure state, it is resistant to ordinary… …
22niobium processing — Introduction preparation of the ore for use in various products. Niobium (Nb) has a body centred cubic (bcc) crystal structure and a melting point of 2,468° C (4,474° F). Of the refractory metals, it has the lowest density and best… …
23Grinding (abrasive cutting) — Sketch of how abrasive particles in a grinding wheel remove material from a workpiece. Grinding is an abrasive machining process that uses a grinding wheel as the cutting tool. A wide variety of machines are used for grinding: Hand cranked knife… …