炭黑添加量对传感器用CuCr合金表面聚酰胺涂层性能的影响

Effect of Carbon Black Content on the Properties of Polyamide Coating on CuCr Alloy Surface for Sensor

为了提高传感器用CuCr合金表面微弧氧化层的耐蚀性能,设置环氧树脂与丙酮比例为5∶3(质量比,下同),通过控制不同炭黑添加量在微弧氧化层表面制得聚酰胺涂层。采用试验测试的方式分析了各组分对涂层耐蚀能力与导电性的影响。研究结果表明:炭黑颗粒含量为10%时,相邻炭黑颗粒在涂层中形成了更紧密的排列状态,对空隙形成了更紧密的填充效果。当炭黑颗粒加入量提高后,形成了更明显的表面缺陷,涂层中无论炭黑颗粒大小还是数量都明显提高。随着炭黑添加量增大,涂层耐蚀性表现出先增加后降低的变化,而炭黑添加量为10%对改善涂层的耐蚀能力是较优的。采用聚酰胺涂层可以实现对微孔密封的效果,使反应活性点数量减少,有效提升涂层耐蚀能力。炭黑颗粒含量为10%时,涂层方阻减小,同时获得了最小的电阻值,达到了较优的导电性能。提高炭黑颗粒含量后,可以连接成导电网络,从而获得最小的涂层电阻。

In order to improve the corrosion resistance of the micro-arc oxide layer on the by experimental tests CuCr alloy surface for sensor,polyamide coatings were prepared by setting different amount of carbon black.The ratio of epoxy resin to acetone was set at 5∶3(mass ratio,the same below).The influence of each component on corrosion resistance and electrical conductivity of the coating was analyzed by experimental tests.Results showed that when the content of carbon black particles reached 10%,the adjacent carbon black particles formed a more compact arrangement in the coating,presenting a more compact filling effect on the voids.When the amount of carbon black particles was increased,more obvious surface defects were formed.And both the size and the amount of carbon black particles in the coating were obviously increased.With the increase of the amount of carbon black,the corrosion resistance of the coating increased first and then decreased.At the carbon black content of10%,the corrosion resistance of the coating was better.The use of polyamide coating could achieve the effect of microporous sealing,so that the number of reactive points was reduced,effectively improving the corrosion resistance of the coating.When the content of carbon black particles reached 10%,the resistance of the coating decreased,and the minimum resistance value was obtained to achieve better conductivity.After increasing the content of carbon black particles,the conductive network could be connected to obtain the minimum coating resistance.