关键词: 化学沉积, 合金, 镍, 钼, 性能

Abstract: The electroless Ni-Mo-P alloy has been deposited from the alkaline bath containing boric acid as a buffer agent and sodium citrate as a complexing agent. The effect of deposition parameters, such as pH and concentration of (NH_(4))_(6)Mo_(7)O_(24)4H_(2)Oon the plating rate, the composition, the structure and the microhardness of the coating was examined. It was found that the presence of molybdenum has an inhibitory effect on the alloys deposition. As a consequence, the percentage of molybdenumin the Ni-Mo-P coatings never reaches high values, which was lower than 20 at%. It was also shown that the deposition condition affects the microhardness of the deposit and almost does not affect the structure of the deposit. Therefore, the microhardness of the deposit depends on the content of molybdenumin the deposit. The corrosion resistance of the deposit in 3.5 Wt% NaCl solution (pH 7.0) was studied by the weight loss test and the electrochemical anodic polarization measurement. The results show that the corrosion resistance of the deposit is better and depends on the deposition parameters, and the weight loss test agree with those of the anodic polarization measurement.

Key words: Electroless deposition, Alloy, Nickel, Molybdenum, Property