COULEE D'UNE FIBRE D'ACIER

摘要

1341774 Continuous casting MONSANTO CO 4 Oct 1971 [5 Oct 1970] 46129/71 Heading B3F [Also in Division C7] Apparatus for producing steel fibres having a diameter less than 254 microns by melt extrusion comprises a crucible assembly 13, Fig. 1, having a base member 14 provided with an insert 18 containing a spinning orifice 19. A helical inductor coil 20 and susceptor 12 surround the crucible to melt steel therein. Molten alloy 16 is forced through orifice 19 by the pressure of inert gas above the melt and the molten stream enters an oxide-forming atmosphere, e.g. air, oxygen, carbon dioxide or carbon monoxide. A stabilizing film of oxide, e.g. of aluminium is thus provided around the periphery of the stream preventing the break-up and allowing the formation of a uniform fibre. If steel alloys are used containing 0À1-1À5% carbon and 0À3 to 3% of oxidizable material, aluminium, berylluim, thorium, zirconium, yttrium or mixtures thereof, then the ultimate tensile strength of the fibre is at least 14,000 kgms/sq. cm. There may be incidental constituents such as chromium, molybdenum, vanadium or silicon.