纳米金属陶瓷复合层多步电沉积工艺及性能  

Multi-step Electrodeposition Process and Properties of Nano-cermet Composite Coating

作　　者：李智[1] 胡德枫 葛毓立[1] 宋万彤 刘崇宇 Li Zhi;Hu Defeng;Ge Yuli;Song Wantong;Liu Chongyu(School of Mechanical Engineering,Dalian University,Dalian 116622,China)

机构地区：[1]大连大学机械工程学院,辽宁大连116622

出　　处：《稀有金属材料与工程》2023年第6期2227-2235,共9页Rare Metal Materials and Engineering

基　　金：国防科技重点实验室基金(6142005180302)。

摘　　要：为提高纳米金属陶瓷复合沉积层性能,采用多步电沉积工艺在合金钢表面制备Ni-TiN-GO(氧化石墨烯)复合沉积层,分析其组织结构、成分、显微硬度、耐磨性和耐蚀性,确定最适宜的多步电沉积工艺,在此基础上对沉积层进行后处理,探究后处理对沉积层耐蚀性的影响。结果表明:三步电沉积工艺获得的沉积层组织性能最好,沉积层与基体结合紧密,厚度为24.6μm,表面均匀致密,晶粒尺寸约为20 nm,晶粒表现为(111)和(200)晶面双择优取向;沉积层显微硬度(HV)为22044.51 MPa,摩擦系数为0.8,磨损机制以微弱磨粒磨损为主;Tafel极化曲线测试表明,三步电沉积层自腐蚀电位为-0.677 V,自腐蚀电流密度为1.71×10^(-5)A·cm^(-2),96 h盐雾试验后,沉积层表面无明显变化;后处理后,三步电沉积层自腐蚀电位正移60 mV,自腐蚀电流密度下降1个数量级。In order to improve the properties of nano-cermet composite electrodeposited coatings,Ni-TiN-GO(graphene oxide)composite electrodeposited coatings were prepared on the surface of alloy steel by multi-step electrodeposition process.The microstructure,composition,microhardness,wear resistance,and corrosion resistance of electrodeposited coatings were characterized and analyzed to determine the optimal multi-step electrodeposition process.On this basis,the coating was post-treated and the effect of post-treatment on the corrosion resistance of coating was studied.Results show that the microstructure and properties of the coating obtained by three-step electrodeposition are optimal.The electrodeposited coating has good bonding with the substrate and its thickness is 24.6μm.Additionally,the coating obtained by three-step electrodeposition has uniform and dense surface,and the grain size is about 20 nm.The grains show double preferred orientations of(111)and(200)planes.The microhardness(HV)of the electrodeposited coating is 22044.51 MPa,and the friction coefficient is 0.8.The wear mechanism is mainly weak abrasive wear.The results of Tafel polarization curve test show that the corrosion potential of the three-step electrodeposited coating is-0.677 V,and the self-corrosion current density is 1.71×10^(-5) A·cm^(-2).After salt spray test for 96 h,the coating morphology barely changes.After post-treatment,the self-corrosion potential of the three-step electrodeposited coating shifts positively of 60 mV,and the self-corrosion current density decreases by an order of magnitude.

关 键 词：多步电沉积 纳米金属陶瓷复合层 后处理 组织性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]