摘要
目的采用混粉电火花加工技术,使用超声电沉积制备的Cu-Si C复合电极加工TC4钛合金,在工作液中混入碳粉进行表面改性,以获取性能优异的加工表面。方法利用Cu-Si C复合电极和Cu电极对TC4钛合金进行成型加工。用扫描电子显微镜(SEM)观察加工后工件的表面形貌和熔凝层断面形貌,并用TR200粗糙度仪测量其表面不同位置的粗糙度值。用硬度仪测量工件熔凝层的显微硬度,用X射线衍射仪对材料强化层进行物相分析。并对电极损耗进行对比分析。结果 Cu电极加工的TC4钛合金表面凹坑深且面积大,熔凝层疏松,粘合性较差。Cu-Si C复合电极加工的TC4钛合金表面放电痕迹大,深度统一,电蚀产物少,熔凝层致密好。利用X射线衍射仪、硬度测量仪和粗糙度仪对试样测量分析显示,Cu-Si C复合电极加工后,表面生成的Ti C峰相高,耐磨性好,表层显微硬度较大,约为基体的6倍,表面平均粗糙度值Ra=2.825μm。复合电极损耗比铜电极损耗降低了18%。结论两种电极加工后,TC4钛合金表面均得到改善,且使用超声电沉积Cu-Si C复合电极加工后的表面质量更好。
The work aims to complete surface modification by processing TC4 titanium alloy with Cu-SiC composite elec- trode prepared by ultrasonic electrolytic deposition and mixing carbon powder into working fluid, so as to obtain surface with excellent properties. TC4 titanium alloy was formed by using Cu-SiC composite electrode and Cu electrode. Firstly, morphology of the machined workpiece and fracture morphology of the melting layer were observed with scanning electron microscope （SEM）, and roughness values in different positions on the surface were measured with TR200 roughness meter. Then micro- hardness of the workpiece＇s melting layer was measured with FM800 hardness tester, phase analysis of the strengthened layer was carried out by using X-ray diffractometer. Finally, electrode losses were compared and analyzed. The surface of TC4 tita- nium alloy machined by Cu electrode featured in deep and large pit, loose melting layer and poor adhesion. The surface of TC4 titanium alloy processed by Cu-SiC composite electrode featured in large traces of discharge, uniform depth, few discharge de- bris and compact melting layer. Measurement analysis from X ray diffractometer, FM800 hardness tester and roughness tester showed that workpiece surface machined by Cu-SiC composite electrode exhibited higher TiC peak, better abrasion resistance and higher hardness. The surface microhardness was about 6 times of the substrate, and average surface roughness value Ra was 2.825μm. Loss of the composite electrode was 18% lower than that of copper electrode. The surface of TC4 titanium alloy is improved, surface of TC4 titanium alloy is improved, and the surface quality of Cu-SiC composite electrode subject to ultrason- ic-electrodeposition is better than that of Cu electrode.
出处
《表面技术》
EI
CAS
CSCD
北大核心
2017年第9期252-257,共6页
Surface Technology
基金
国家自然科学基金(51105235)~~
