超声作用下的电铸铜微观结构与机械性能

为了改善电铸微细部件的机械性能,通过改变电铸工艺参数以及在电铸铜过程中引入超声场,得到具有不同微观结构特征的电铸铜材料.采用金相显微镜、扫描电子显微镜观察电铸铜层微观形貌,用X射线衍射分析铸层晶面择优取向,并用维氏硬度计和拉伸试验机分别测试电铸铜层机械性能.实验结果表明,超声作用下电铸和普通电铸得到的铜层表面均为(220)晶面择优取向,并且超声电铸铜层的择优取向程度更强.超声电铸铜层晶粒为细小柱状晶结构,与普通电铸铜相比,其抗拉强度和显微硬度均提高约30%.在电铸溶液中氯离子(Cl-)质量浓度为60mg/L时,铸铜层晶粒比其他Cl-质量浓度时晶粒更细小,抗拉强度和塑性也更高.在电铸过程中引入超声场能改善电铸铜层的微观结构,并提高电铸铜的机械性能.

Effects of ultrasonic on microstructure and mechanical properties of electroforming copper layer

To improve the mechanical properties of electroforming micro components,the electroformed copper layer with different microstructures was prepared by introducing ultrasonic-assisted technique and changing the process parameters during electroforming. The microstructure of the electroformed copper layer was observed by optical microscope (OM) and scanning electron microscope (SEM). The preferred orientations of the layer were characterized by X-ray diffraction (XRD). The mechanical properties were evaluated with a Vicker’s hardness tester and a tensile tester. The results show that the electroformed copper layer is textured with Cu-(220) both in ultrasonic and non-ultrasonic conditions,and the copper layer’s preferred orientation electroformed in ultrasonic condition is stronger than that of in normal condition. The analysis of mechanical properties shows that the tensile strength and microhardness of the copper layer both raise 30% and the microstructure is fine columnar crystals when electroformed under the condition of ultrasonic agitation. When the concentration of Cl-in solution is 60 mg/L,the grain of the copper layer distributes more uniformly,the tensile strength and the ductility of it are both higher than those in other Cl-concentrations. Meanwhile,the integral mechanical properties of the electroformed copper electroformed in ultrasonic condition are significantly improved in comparison with the pure copper deposit.