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介绍了铝合金化学镀镍磷合金镀层的初期析出行为、组织和相结构镀态下，镀层截面组织为黑白分明的层状组织，平面组织呈同心环状。低磷镀层的相结构是磷在镍中的过饱和固溶体，而高磷镀层为非晶态镍磷合金。随着加热温度的升高，低磷镀层首先析出NixPy，然后析出Ni3P相。高磷非晶态镀层首先晶化转变成NixPy相和Ni3P相，然后析出Ni相，镀层相结构最后都为Ni＋Ni3P＋NixPy相。
The initial precipitation behavior of the electroless nickel-phosphorus alloy coating was introduced. The microstructure of the coating and the phase structure were as follows: the cross-section of the coating was a black-and-white layered structure with concentric rings. The phase structure of the low-phosphorus coating is a supersaturated solid solution of phosphorus in nickel, whereas the high-phosphorus coating is an amorphous nickel-phosphorus alloy. With the increase of the heating temperature, the low-phosphorus coating precipitates NixPy first and then precipitates the Ni3P phase. The high-phosphorus amorphous coating first crystallized and transformed into NixPy phase and Ni3P phase, then precipitated Ni phase, and the final phase structure of the coating was Ni + Ni3P + NixPy phase.