黄铜温度计套管汞裂破坏的观察

Observation of Brass Thermometer Tube Cracking

对一起黄铜汞裂破坏的构件进行形貌和金相分析,结合能谱测试,讨论了汞裂破坏形式、汞裂破坏机制,汞裂与一般沿晶型应力腐蚀破裂及晶间腐蚀的差别。指出汞裂是汞或其蒸气沿应力作用造成的缺陷部位深入组织内部,通过物理或化学作用与原来的组织在晶界生成强度低的新相,破裂沿新相区域出现。

A brass component cracked in mercury was analyzed with macroscopic and metallographic technique. Combined with energy spectrum test, the form and mechanism of mercury induced cracking were discussed. The differences between mercury induced cracking and intergranular stress corrosion cracking, mercury induced cracking and intergranular corrosion were compared. It was pointed out that mercury induced cracking only happens in areas of intergranular new phase which produced by physics or chemistry action of mercury and its vapor together with original structure and was weaker than the original.