摘要 |
A thermal black layer is produced on the surface of a component of molybdenum, nickel, iron, tungsten, copper or an alloy of two or more of these metals by (a) applying a 1-10 microns thick layer of aluminium and opt. one of the above metals; (b) heating the layer and the component to form an aluminium compound with one of the above metals, in a non-reactive atm.; and (c) thermally oxidizing the compound at 950-1200≰C in a wet hydrogen atm. to convert the aluminium into aluminium oxide. |