XPS-法研究高温弱酸性介质中化学镀NiCuP非晶态合金的腐蚀行为

THE CORROSION BEHAVIOR OF ELECTROLESS Ni\|Cu\|P ALLOY IN WEAK ACID MEDIUM FULL OF CO 2 AT HIGH TEMPERATURE BY XPS

利用XPS法研究了化学镀Ni Cu P非晶态合金在 1 4 0℃、pH =5 .0、CO2 饱和的Na2 SO4 溶液中处于不同电位下的表面膜组成 .结果表明 ,处于不同电位下的Ni Cu P合金表面膜中皆有富P和富Cu现象发生 ,是膜中Ni选择性溶解的结果 .H2 PO-2 和HPO2 -3 吸附层的存在是合金发生钝化的原因 .

The surface composition of amorphous Ni\|Cu\|P alloy at different potentials in 140℃,pH=5.0,2% Na 2SO 4 electrolyte full of CO 2 was studied by XPS. The results showed that the enrichments of elements P and Cu on the alloy surface could be found in each specimen,which was the result of the selective dissolution of Ni but not the cause of passivation.The existence of adsorption layer of hypophosphite and phosphite anions was the main reason of alloy passivation. Although the oxidation products of Ni and Cu did not contribute to the passivation,they changed with the change of the potential