摘要 |
<p>In a boriding process comprising coating a metal surface with a thin layer of a boron source and then heating the metal in a gas atmos. at 700-1100 deg.C, the novelty is that the boron source layer is covered with an insulating material which inhibits gaseous diffusion and heating is carried out in a carburising, nitriding or carbonitriding atmos. The process allows relatively cheap gas atmospheres to be used and allows simultaneous carburising, nitriding or carbonitriding or non-coated regions of the metal surface.</p> |