论文部分内容阅读
锡锌合金为银白色、光亮、细致柔软及可抛光,经钝化处理后,为无色或淡黄色。锡锌合金具有一系列可贵性质,它在电化学性质上,可以保护钢铁,同时在化学稳定性方面也能超过昂贵而稀少的镉。镀层中含锡量占75～85％合金镀层,其优点为耐盐水腐蚀,可焊接。作为家用煤气表的电镀层能满足设计使用要求。镀液的选择以往锡锌合金在国内外都有人试验过,当时多采用碱性氰化物,氟化物-氯化物、氟硼酸盐,焦磷酸盐,葡萄糖酸等电镀溶液。前三种溶液均有毒。上叙溶液的共同特点是:当电流密度变化时,镀层合金成分的比例变化较大,因而使用价值不大。笔者所在工厂,家用煤气表生产批量相当大。按GB6968—86家用煤气表关于镀层的选择规定,采用的金属镀层必须能耐被测气体的腐蚀和耐湿,一般零
Tin-zinc alloy is silver white, bright, delicate and soft and can be polished, after passivation treatment, colorless or light yellow. Tin-zinc alloys have a range of valuable properties that electrochemically protect steel while also exceeding the expensive and scarce chemical resistance of cadmium. Plating layer containing 75 to 85% tin alloy coating, the advantages of salt water corrosion, welding. As a household gas meter plating to meet the design and use requirements. The choice of bath In the past tin-zinc alloy has been tested at home and abroad, when more use of alkaline cyanide, fluoride - chloride, fluoride borate, pyrophosphate, gluconic acid and other plating solution. The first three solutions are toxic. The common feature of the Syrian solution is: when the current density changes, the proportion of coating alloy composition changes, so the use of little value. The author where the factory, home gas meter production volume is quite large. According to GB6968-86 household gas meter on the choice of coating, the metal coating used must be able to withstand the corrosion of gas and humidity, the general zero