GB201589A - Alloys - Google Patents

Abstract

201,589. Saltrick, W. R. March 7, 1922. Alloys.-High-speed steels or tool steels containing in addition to iron and carbon a number of the metals tungsten, chromium, molybdenum, vanadium, and cobalt, are made by reducing in a furnace a mixture comprising a silicon-containing reducing-agent and reducible ores or compounds of some or all of the required metals, and adding the product to a molten-metal bath either contained in the furnace or in a separate furnace or container. The reducing-agent may be silicon, ferro-silicon, silicides of calcium, aluminium, boron or magnesium, or silicon alloys of magnesium or of aluminium and calcium; and some aluminium or an alloy of aluminium or calcium may be added. A carbide may also be used as part of the reducing-agent. The ores or compounds and the reducing-agents are preferably briquetted, with or without the addition of fluxes, or they may be packed in thin iron containers. A tipping furnace may be used to facilitate the discharge of slag. The alloy obtained may be refined by means of compounds such as chromite or oxide of iron, or by a blowing operation, or by the use of a refining slag, or by two or more such methods. Additions of ferro-alloys, and of carbon in the form of a high-carbon alloy, may be made before or after refining, to adjust the final composition to that required. Reference has been directed by the Comptroller to Specifications 148,380 and 174,312.