Improvements in or relating to coating metals with composite metallic aluminium compounds

摘要

750,637. Making cased or compound forms. TELEFUNKEN GES., [formerly TELEFUNKKEN GES. FUR DRAHTLOSE TELEGRAPHIE]. Jan. 12, 1954 [Jan. 12, 1953], No. 827/54. Class 83 (2). In a method of forming a black aluminium compound heat-radiant coating on metals, a layer of aluminium is first applied as by coldrolling and is heated to form the intermediate compound at the junction, the unconverted aluminium on the surface being subsequently removed. Aluminium is applied to nickel, iron, tungsten or molybdenum sheet, strip, wire, mesh, &c. and heated in a vacuum or protective gas such as hydrogen at approximately 600‹ C. for 10 minutes. The surface aluminium is then removed as by a weak solution of sodium hydroxide, soda or hydrochloric acid or by forming an amalgam in mercury or mercury salts. Electrodes for electron discharge devices may be punched from the coated sheets or preformed electrodes may be given the black coating.