| 摘要 |
<p>Metal substrates may be chromised by subjecting them to a diffusion heat treatment in which the substrate is placed in contact with a flexible carrier sheet having adherent thereto or incorporated therein chromium metal or an alloy thereof or a reducible compound of chromium. Particularly suitable flexible carrier sheets are made from asbestos paper. If chromium metal or an alloy thereof is employed it is necessary that a halide is also present. This may be present either on the surface of the substrate itself, on the flexible carrier sheet bearing the chromium or its alloy or on a separate sheet of flexible carrier material.</p> |
