退火温度对铜基微纳结构层润湿性的影响研究

Research on the Effect of Annealing Temperature to Wettability of Micro-nano Structure Layer on Copper Base

采用电火花技术在铜基表面制备了微纳结构层,分别在空气和H2+Ar混合气环境下,温度为100、200和300℃时进行退火处理30 min,研究退火温度对铜基微纳结构层润湿性的影响。退火处理前后的试样采用扫描电镜和能谱仪分别进行形貌和成分分析,结果显示微纳结构层具有典型电火花加工形貌特征,表面润湿性受尺度效应和钝化膜的共同作用。空气环境下,低温区处理(室温至200℃)的试样表面钝化膜不连续,尺度效应明显而呈疏水性;高温区处理(约300℃)的试样则因为钝化膜连续而呈现亲水状态。H2+Ar混合气环境下处理的试样表面由于还原反应而无钝化膜作用,仅有尺度效应而保持疏水性。

The electrical discharge machining technology is used to prepare a micro-nano structure layer on the copper surface. The samples are annealed in air and H2＋Ar mixed gas for 30 min.,and the annealed temperature is 100 ℃,200 ℃ and 300 ℃,respectively. The effect of annealing temperature to the wettability of micro-nano structure layer on copper base is investigated in this study. The scanning electron microscope is employed to observe the morphology of the samples before and after annealing treatment. And the chemical compositions of samples are detected by energy dispersive spectrometer. The results indicate that the micro-nano structure layer has some typical characteristics of electrical discharge machining with hydrophobic property.The results of wettability indicate that the wettability property of surface is affected by combined action of scale effect and passive film. In air,the passive film at low annealing temperature（〈 200 ℃） is discontinuous and the scale effect is so significant that the surface shows hydrophobic property. However,the surface annealed at high temperature（ 〉300 ℃） shows hydrophilic because of the continuous passive film. Moreover,there is no passive film covered on the surfaces annealed in H2＋ Ar mixed gas due to the reduction reaction. And there is only a scale effect affectting the surface to show hydrophobic property.