Study On Characterization Of Ni-plating By High Frequency Pulse Currents

:The content of this study is to test different parameters such as pulse frequency, ton/off and current density on coating deposition rate, wear resistance and internal stress of Ni-plating. According to relevant documents and to select the pulse frequency of ranging from20to140kHz. ton/offfrom0.2to0.4and current density Jm from2.5to10A/dm2. In the course of the study, adopt the orthogonal experimental design method and use high frequency pulse power in the conditions of the selected pulse parameters nickel plating layer, analyzed and discussed the impact of various pulse parameters on the deposition rate, the internal stress and wear resistance of nickel-plated.The results show that the deposition rate of nickel coating layer increases as the pulse frequency and current density, and increases with the ton/off then decreases. To get the fastest deposition rate, we can choose100kHz,0.35as ton/off, and10A/dm2as the current density. But given the coating layer is not very satisfactory when using too large current density, the current density can be properly reduced.At the same time as the pulse frequency increases, coating the stress first decreases and then increases, the minimum at60kHz;0.2of ton/offand the current density of3.5A/dm2has minimum respectively.In resistance test, the pulse frequency60kHz, pH=3.8, the current density Jm=2.0A/dm2, and6.0A/dm2, duty cycle r=0.4at a wear rate to the minimum. This indicates that under these conditions the wear resistance of nickel-plated is better.However, at the same time to meet the deposition rate of nickel-plated, internal stress and wear resistance which are made to good, the conditions is not easy to find. It requires us to determine the premise of its intended use, to find what the nature of these uses are more focused on the nickel-plated to find to meet the requirements of plating conditions.