GB870213A - Apparatus for and method of casting grain-oriented ingots - Google Patents

Abstract

<PICT:0870213/III/1> <PICT:0870213/III/2> A method for casting grain-oriented ingots comprises pouring a molten metal which solidifies in the cubic lattice form into a mould 20 (Fig. 3) having at the bottom a seed body 11 of solid metal having cubic lattice form and having the atoms of at least one area of the surface 14 so arranged that planes forming unit cube faces thereof are parallel to the surface 14 melting the surface of the body 11, and then causing the molten metal to solidify by extracting heat through the body of solid metal 11. The metal may be iron containing up to 5% of silicon or molybdenum, or up to 8% of aluminium. The seed body 11 is cut from a casting composed of columnar grains having parallel longitudinal axes and is placed in the mould with the longitudinal axes horizontal. After the surface 14 has been melted back to a plane 30 (Fig. 4), coolant is passed through a heat exchanger 21 (Fig. 3), and an ingot is obtained consisting of grains such as 161 and 171 (Fig. 4) having parallel orientation which have grown on the grains 16 and 17 in the body 11 which had unit cube faces parallel to the surface 14, to the ultimate exclusion of growth on other grains. The mould walls are preheated by a removable electric heater before the molten metal is poured in, to ensure that the heat is substantially all extracted through the cooled bottom of the mould. Specification 870,209 is referred to.