These are graphite, high silicon cast iron, lead silver alloy, platinum, and even scrap steel rails.

所用材料有石墨、高硅铸铁、铅银合金、铂、甚至废钢轨等。

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These are graphite, high silicon cast iron, lead silver alloy, platinum, and even scrap steel rails.

所用材料有石墨、高硅铸铁、铅银合金、铂、甚至废钢轨等。

youdao