Metals or alloys made by redn. of chlorides with hydrogen - involves heating starting materials to temp. above their b.pt. but below m.pt. of prod.

摘要

One or more chlorides of V or the metals in Gps. VIa, VIIa and VIII of the periodic system are evaporated, and fed at a temp. above their b. pt. but below the m. pt. of the metals, into a reactor, so they can be reduced by hot H2 to fine metal particles which can be agglomerated. Steel or alloy steel is pref. made by leaching iron ore or scrap with HCl to form iron chlorides, which are recovered by crystallisation and treated in the reactor with H2 and a hydrocarbon gas so that steel particles contg. carbon are obtd. Fractional crystallisation can be used to separate FeCl2 from FeCl3, the latter being evaporated and sprayed into the reactor. Another metal chloride, esp. of Ni and/or Cr and/or Mn is pref. fed into the reactor for mfg. alloy steel powders. Esp. the mfr. of steel powders, which can be used in powder metallurgy to make prods. such as stainless steel strip, and/or deposited on a substrate.