材料期刊网

利用XRD研究了电刷镀Ni--P镀层经不同温度热处理后的组织结构. 研究表明, 镀态电刷镀Ni-P镀层呈非晶态; 热处理温度在350 ℃以上时, Ni, Ni₃P形核生长; 热处理温度在500 ℃以上时, 镀层中有NiO生成. 镀层的结晶度与热处理温度呈典型的“S”形关系变化,晶化激活能为(237.9±10.46) kJ?mol^-1. 随热处理温度升高, Ni的晶格常数先增大后减小;而Ni₃P的晶格常数a随热处理温度上升而变小, 而c略微增大; Ni和Ni₃P晶粒大小随热处理温度的上升均增大; Ni和Ni₃P晶体长大的表观活化能分别为(66.85±3.15) kJ?mol^-1和 (133.41±4.69) kJ?mol^-1, 前者仅为后者的50%, 表明在热处理过程中Ni晶体有优先长大的趋势.

The effects of heat-treat temperature on the structural of electro-brush plating Ni-P coatings were investigated using X-ray diffraction (XRD) analysis. The results show that the eletro-brush plating Ni-P coating is mainly in amorphous state. When heat-treat temperature above 350 ℃, Ni and Ni₃P crystal appear, NiO is generated as the heat-treat temperature is above 500 ℃. There is a typical S-shaped relationship between the crystallinity and heat-treat temperature. The activation energy of crystallization is (237.9±10.46) kJ±mol^-1. As the heat-treat temperature rises, Ni crystal cell parameter a increases firstly and then decreases, Ni₃P crystal cell parameter a decreases but $c$ has a little increase. The crystal size of both Ni and Ni₃P has some increase with the rise of heat-treat temperature. The activation energies for the growth of Ni and Ni₃P are (66.85$\pm$3.15) kJ?mol^-1 and (133.41±4.69) kJ?mol^-1, respectively, and the great disparity imply that Ni crystal has dynamic for preferred growth.\par