电压对电刷镀三价铬镀层性能的影响

Effect of voltage on properties of electrobrush plated chromium coating from a trivalent chromium bath

在45钢表面电刷镀得到三价铬镀层,镀液组成和工艺条件为:Cr2(SO4)36H2O 0.4 mol/L,甲酸铵0.5 mol/L,氨基乙酸0.5 mol/L,H3BO30.6 mol/L,NaH2PO2 H2O 0.3 mol/L,pH=1.5,温度50°C,镀笔移动速率15 cm/s。研究了电压对镀铬层显微结构、表面粗糙度、厚度、显微硬度和耐磨性的影响。随电压增大,镀层厚度增大,显微硬度和耐磨性均先提高后降低。电压为14 V时,镀层的表面平整,粗糙度为2.387μm,显微硬度为602 HV,耐磨性最好。

Chromium coating was prepared on 45 steel surface by electro-brush plating from a trivalent chromium bath comprising Cr2(SO4)36H2O 0.4 mol/L,ammonium formate 0.5 mol/L,glycine 0.5 mol/L,H3BO30.6 mol/L,and NaH2PO2 H2O 0.3 mol/L at temperature 50°C,pH 1.5,and brush movement rate 15 cm/s.The effect of voltage on the microstructure,surface roughness,thickness,microhardness,and wear resistance of chromium coating was studied.With the increasing of voltage,the thickness of chromium coating was increased,while the microhardness and wear resistance were increased initially and then decreased.The coating obtained at a voltage of 14 V was smooth,and had a roughness of 2.387μm,a microhardness of 602 HV,and the best wear resistance.