Both conditions can be detected by a temper etch (i. e., nital etch) inspection of the base metal.

两种情况在对本体金属的回火蚀刻检查中会发现。

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NITAL ETCH : Process of checking surfaces of ground product for cracks or burns by use of a series of acids and neutralizers.

硝酸酒精腐蚀检验：通过使用一系列的酸性或中性溶液检查磨削后零部件表面是否有裂痕或磨削烧伤。

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