脉冲电沉积镍-铜合金

采用脉冲电沉积技术在304不锈钢表面制备Ni-Cu合金镀层,镀液组成和工艺条件为:NiSO4?6H2O 200g/L,CuSO4?5H2O 10 g/L,十二烷基硫酸钠0.2 g/L,柠檬酸钠80 g/L,糖精0.2 g/L,pH 4.0,温度25°C,搅拌速率30 r/min,平均电流密度40~120 mA/cm2,脉冲频率0~100 Hz,占空比20%~90%,时间30 min。研究了平均电流密度、脉冲频率和占空比对Ni-Cu合金镀层的元素组成、表面形貌和显微硬度的影响,得到较优的工艺参数为:平均电流密度40 mA/cm2,脉冲频率50 Hz,占空比60%。该条件下所得Ni-Cu合金镀层由质量分数分别为56.53%和43.47%的Ni和Cu组成,呈“菜花”状形貌,结晶细致、均匀,显微硬度为614.4 HV。

Pulse electrodeposition of nickel–copper alloy

Ni-Cu alloy coating was prepared on 304 stainless steel by pulse electrodeposition from a bath comprising NiSO4·6H2O 200g/L,CuSO4·5H2O 10 g/L,sodium dodecyl sulfate 0.2 g/L,sodium citrate 80 g/L,saccharin 0.2 g/L,at temperature 25°C,pH 4.0,stirring rate 30 r/min,average current density 40-120 mA/cm2,pulse frequency 0-100 Hz,and duty cycle 20%-90%for 30 min.The effects of average current density,pulse frequency,and duty cycle on the elemental composition,surface morphology,and microhardness of Ni-Cu alloy coating were studied.The optimal process parameters were determined as follows:average current density 40 mA/cm2,pulse frequency 50 Hz,and duty cycle 60%.The Ni-Cu alloy coating obtained under the above conditions is composed of 56.63wt.%Ni and 43.37wt.%Cu,has a cauliflower-like structure composed of compact and uniform crystals,as well as a microhardness of 614.4 HV.