摘要 |
A crucible for containing molten magnesium, and a process for forming the crucible. The crucible is formed from ferritic stainless steel, and particularly type 444 stainless steel plate. The method involves forming ferritic stainless steel plate into component parts of the crucible, while maintaining the ferritic stainless steel plate at temperatures above about 200 DEG F. but below the "blue brittle" temperature range. Further, the method involves special techniques for welding the crucible parts. Specifically, the crucible parts are preheated to a temperature of 100 DEG -150 DEG C. and are completely welded by a process utilizing multiple welding passes with a special metal inert gas shielded welding technique before any cool down of the crucible parts below 100 DEG C. is allowed. The welds extend completely through the crucible walls, which are the thickness of steel plate, and completely incorporate the crucible parts while being essentially free of cracks.
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