Study of single-metal multi-nanometer electrodeposition chromium layer

The cathode process of pulse chromium electroplating was studied by the pulse electrodeposition and additive technologies; furthermore, the single metal unlimited multi-nanometer structure of electrodeposition chromium coating was designed. The AFM results showed that more perfect unlimited multi-nanometer chromium coating was obtained, the thickness of single chromium layer and the scale of crystal particle were about 100 nm, respectively, the angle between coating and basement was about 10°, the growth direction of crystal particle was paralleled to the basement with 10°; SEM results showed that the coating structure was compact and without defect; the salt spray corrosion testing results showed that coating could tolerance to neutral salt spray corrosion resistance for 980 h without speck of rust, and in the case of simulating underground corrosion experiment with Anhui XINJI mine water, the speck of rust was not appeared for 298 days; the results of metalloscope and flexural cathode experiment showed that more compact chromium layer with smaller inner stress was obtained. The optimum pulse parameters of this subject were shown as follows: Tc = 1 min, Ta = 0.5 s.