| 摘要 |
<p>The process is characterised by the fact that, before drawing, a salt of the alkaline metal group formed by Li, Na, and K, and of an anion which is chemically inert with regard to the essential metal of the sheet chosen from among the phosphates is deposited on the drawing tools. To deposit the salt, preferably, a solution of said salt is applied to the tools or to the sheet metal.</p> |
