黄铜拉链苯并三氮唑-硝酸镧-钼酸钠钝化工艺

Process for passivation of brass zipper from a bath containing benzotriazole, lanthanum nitrate, and sodium molybdate

开发了一种黄铜拉链高效钝化工艺,钝化液以苯并三氮唑(BTA)为主,添加了少量硝酸镧和钼酸钠。探讨了钝化液配方、钝化温度和时间对经不同氧化着色工艺处理的黄铜拉链钝化效果的影响。结果表明,最佳钝化温度为30°C,钝化时间为2min。适用于红古铜色、仿金色及仿银色拉链的钝化液配方为:BTA3～4g/L,La(NO3)3.6H2O0.3～0.4g/L,Na2MoO4.2H2O0.6～0.8g/L,聚乙二醇60001g/L。上述配方简单且安全无毒。经钝化及涂油处理后,黄铜拉链的耐蚀性和耐热性明显提高。

An efficient passivation process was developed for brass zipper. The passivation bath is based on benzotriazole （BTA） with a small amount of lanthanum nitrate and sodium molybdate. The effects of bath composition, temperature, and time on passivation effect of the brass zippers treated by different oxidation coloring processes were studied. The results showed that the optimal passivating temperature and time are 30 ~C and 2 min, respectively. The passivation bath comprising BTA 3-4 g/L, La（NOa）3.6H20 0.3-0.4 g/L, Na2MoO4.2H20 0.6-0.8 g/L, and PEG-6000 1 g/L is easily prepared, environmentally safe, and suitable for the brass zippers in red bronze, imitation gold, and imitation silver colors. The passivated brass zippers have improved corrosion and heat resistance after painting.