| 摘要 |
750,059. Extruding. GOLDSCHMIDT AKT.-GES., T. April 27, 1954 [May 11, 1953], No. 12191/54. Class 83 (4). Pyrophoric flints having cores or inserts of light metal are made by extruding a composite billet comprising an outer part b composed of an extrudable mischmetall (cerium)-iron alloy and an insert or core a of magnesium or magnesium-containing light metal alloy in solid or pulverulent form. A core of magnesiumcontaining alloy formed by machining or casting may be inserted in a cast hollow billet of the mischmetall-iron alloy or the latter may be cast around the core. Magnesium or magnesium-containing wires or a tube may alternatively be used as the core. A pulverulent core of cerium-magnesium compound containing more than 40 per cent of magnesium may be used. The core may alternatively be of an aluminium alloy containing 4 per cent copper and 1 per cent magnesium. Specification 682,185 is referred to. |
