热处理对化学镀Ni－Mo－P合金耐蚀性能的影响及其机理

Effect of Heat Treatment on Corrosion Performance of Electroless Ni-Mo-P Deposit Alloy and Studies of Its Anti-Corrosive Mechanism

对于经２００～７００℃热处理的化学镀Ｎｉ－Ｍｏ－Ｐ的合金镀层，测试了其在５％ＮａＣｌ溶液中的腐蚀性能。结果表明，随温度的提高，合金的自腐蚀电位均正向移动；腐蚀速度随温度的提高，呈现先升后降的变化趋势。经２００～６００℃热处理，都将使合金的耐蚀性有不同程度的下降。合金结构中晶格和相的变化，保护性氧化膜的生成，以及合金与基体间Ｆｅ－Ｎｉ－Ｍｏ－Ｐ扩散层的形成等，分别对合金耐蚀性能变化起了重要作用。

Some methods of corrosion test were employed to test the corrosion perfor-mance(in 5%NaCl solution)of the Ni-Mo-P deposit alloy which was heat-treated in the range of 200～700℃. The result of static corrosion potential test showed that the potential of the deposit would be noble with increasing the temperature of heat treatmeat.From the point of view of thermodynamics,the stability of the deposit in corrosive media would increase. The results of corrosive rate test(dynamics)showed that the corrosion rate of the deposit increased first and then decrease with ipcreasing the temperature of heat treatment.Anti-corrosion performance of the deposit would drop to a different degree in the rapge of 200～600℃, XRD, XPS and AES surface analysis techniques were used to investigate the mechanism of anti-corrosive performance which affected by heat treat-ment.The result showed that the changes of lattice and phase in structure of the deposit alloy,the protective oxide film forming on the surface of the deposit alloy and the form-ation of the Fe-Ni-Mo-P diffusion layer between the deposit and the basis-metal played important roles in the changes of corrosion performapce respectively in the different range of heat treatment.