GB388535A - Improvements in or relating to the production of ply metal - Google Patents

Abstract

388,535. Making ply-metal sheets and rods. TREMBOUR, M. R., 490, Lincoln Avenue, Beaver, Pennsylvania, U.S.A. Jan. 5, 1932, No. 315. Convention date, Dec. 3, 1931. [Classes 83 (i), 83 (ii), and 83 (iv).] Casting composite articles ; welding ; working at specified temperatures.-Ply-metal bands, strips, sheets, bars, &c. are made by casting ferrous metal around an insert, of chromium, nickel, stainless steel or other noble metal, having one surface in weldable condition and another in a weld-resisting condition to form an ingot, applying pressure to the hot ingot, cropping the edges to expose the insert, and separating at the weld-resisting surface. Stainless steel sheets 4 are prepared by coating one side with sodium silicate solution, dusting with powdered silica, alumina, magnesia, chromic oxide, &c., and drying and sand-blast, ing the other side. One or more sheets may be inserted singly in a mould or they may be placed in pairs with the coated sides 6 in contact and connected, as by spot-welding, at corners or edges. Mild steel is then poured into the mould, the ingot heated to 2200‹ F., and rolled to weld and, if desired, to give any desired thickness. If the body is to be formed of medium- or high-carbon steel, carbon is prevented from damaging the properties of the noble metal 38, Fig. 12, by placing against its weldable surface a weldable sheet 37 of low-carbon steel which, after pouring and rolling, becomes welded to the body of highercarbon steel and to the noble metal. The compound body may be rolled, pressed, or forged to any desired form and, if necessary, annealed before trimming and separating. The molten ferrous metal is preferably deoxidized, by aluminium or silicon &c., and freed, if necessary, from products thereof, such as alumina, before casting.