电镀氢脆故障及应对措施

电镀过程中作为阴极的被镀零件在获得镀层的同时在零件金属内部也渗入了氢,如果该零件金属对氢脆敏感、又有拉应力存在时便可能发生氢脆,使零件断裂,甚至诱发事故.介绍了几例典型的氢脆故障,结合实例分析指出,渗入金属内部的氢是可逆氢,可以通过加热烘烤排出,以避免事故发生.

Failure of Electroplated Metal Parts Duo to Hydrogen Embrittlement and the Countermeasures

Several examples were provided for the case study of the failure of electroplated metal parts due to hydrogen embrittlement and of the countermeasures to eliminate it.It was pointed out that,in the electroplating process,the metal parts acting as the cathode could be coated with the coatings of various other metals(such as Zn,Cd,Cr,etc.).However,the hydrogen generated in the electroplating oxidation-reduction reactions could also permeate into the metal part substrate and the inner layer of the coatings as well.The entrapped hydrogen could cause fracture and even catastrophic failure of the electroplated metal parts which are liable to hydrogen embrittlement and subject to tensile stress.Therefore,it is imperative to get rid of such hydrogen embrittlement of the electroplated metal parts in terms of the operation reliability and safety.Fortunately,the permeation of the hydrogen into the substrate and inner layer of the electroplated coatings was reversible, i.e.,the hydrogen permeated into the metal substrate and inner layer of the electroplated coatings could be removed by heating properly.This could be essential to avoiding the failure of the electroplated metal parts due to hydrogen embritllement.