转化膜：对金属进行化学或电化学处理所形成的含有该金属之化合物的表面膜层。

Conversion film: chemical or metal electrochemical treatment by the formation of the contains the metal surface membrane layer of the compounds.

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这对恢复出土铁器的面貌及进一步化学稳定转化铁器表面的锈层都具有重要的作用。

So it is important to discover the original shape of excavated iron antiquities and stabilize the rust of iron surface.

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