全光亮镍磷合金镀层的耐蚀性

采用个性盐雾实验、浸泡实验和阳极极化曲线测试了全光亮镍磷合金镀层耐蚀性.盐雾实验表明：磷含量为128mass%～153mass％的镀层耐蚀性能最好，磷合量提高到201mass％后，耐蚀性下降；热处理温度在200℃以下时，对镀层耐蚀性影响不大，超过300℃以上，镀层耐蚀性明显下降；浸泡实验表明Ni-P合金镀层与1Cr18Ni9Ti相比，在酸性、碱性和氯离子水溶液中耐蚀性能较好，但不耐硝酸、硝酸盐等强氧化性介质的腐蚀；阳极极化曲线测试表明，磷含量为12.8mass％的镀层在10％HCl、5％NaCl、20%NaOH和3.5％FeCl-3溶液中，均表现出了优异的耐蚀性能.磷合量为20.1mass％高磷镀层在20％NaOH中耐蚀性能优异. 

CORROSION RESISTANCE OF AN ENTIREBRIGHT NICKLE-PHOSPHORUS ALLOY COATING

Corrosion resistance of an entire-bright nickel-phosphorus alloy coating was studied by means of salt spray test,immersion test and anodic polarization etc.The result of salt spray test indicates that the corrosion resistance of coatings containing 12.8%～15.3 mass% P is the best,and the corrosion resis-tance decreases when phosphorus content in-creased to 20.1mass%;Effect of heat treatment below 200℃ on corrosion resistance is small, but the corrosion resistance decreases ob-vious-ly after heat treatment above 300℃.The result of immersion test shows that the corrosion resistance of coatings is good in acid,alkalescence and Cl\+- solutions,which is more or less camparable with that of 1Cr18Ni9Ti.But the coatings show poor corro-sion resistance in oxidation medias,such as nitric acid and nitrate.Anodic polarization curve displays that the coating containing 12.8%P is excellent in 10%HCI,5%NaCl,201%NaOH and 3.5%FeCl-3 solutions,and however the coating containing 20.1% P is excellent in 20%NaOH solution. 