GB1300433A - Slip casting - Google Patents

Abstract

1300433 Production of sintered metal articles by slip casting BATTELLE DEVELOPMENT CORP 26 May 1970 [26 May 1969] 25131/70 Heading C7D Sintered metal articles of e.g. Fe, Co, Ni, Cu, Mo, W or alloys, are produced by slip casting a slip of a reducible compound of the metal having at least 35% wt of the particles less than 10 microns diameter, reducing the compound to metal and then sintering. The compounds are preferably the oxides with a maximum average particle size of 6 microns with at least 50% under 1 micron. Up to 50% volume of metal particles may be included in the slip. The preferred iron oxide is that formed by spray drying spent pickling liquor containing HCl and FeCl 2 . The Fe 3 O 3 formed is ball milled to the required size e.g. for 1-10 hours, made into a slip with water, cast into a plaster mould, dried, reduced at 1200‹ Fm H 2 and then sintered in H 2 at 2100‹F. Two green slip cast articles may be pinned together by abutting articles prior to reducing and sintering. A wet slip may be interposed between the abutting pieces. Alternatively a green slip cast may be placed in another mould and a further slip cast around it.