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Experts say that the field of magnesium die castings that can be used in automobiles can be roughly divided into two categories: one is to replace the original use of other materials for die casting; the other is to use welded steel or aluminum plates until now. The occasion of the material. For the former, the most common is to replace aluminum die-casting parts with magnesium die-casting parts. Although the two materials have the same casting characteristics, it is of course more reasonable to use magnesium if the weight and cost factors are comprehensively measured.