| 摘要 |
<p>A surface preoxidation of the substrate (5) is carried out by placing the substrate in contact with an oxidant gas excited in a cold plasma, the substrate (5) being placed in the post-discharge of the plasma flow and heated to a temperature lower than 480 °C. At a temperature lower than 500 °C, metal boride is deposited on the preoxidized substrate (5). The deposition of boride is obtained by placing in contact with each other and with the substrate (5) a metal halide, a boron compound and a reducer element, in the form of gas substances. At least one of the gas substances is excited in a cold plasma. The process is particularly intended to coat the internal surface or the external surface of the lining tube of zirconium alloy with a zirconium boride layer which absorbes the neutrons.</p> |
