组织结构的演变
(1. 山东轻工业学院 机械工程学院，轻工装备先进制造与测控技术实验室，济南 250353)
(2. 淄博市新材料研究所，淄博 255040)
摘 要: 用XRD定量分析法并结合扫描电镜形貌观察，研究化学沉积高磷(13.3%)含量的Ni-W-P镀层在不同热处理条件下的晶化程度、晶粒尺寸及晶格应变等组织结构的演变规律。结果表明：高磷非晶态镀层在退火晶化过程中，Ni3P相的体积分数始终高于Ni相的，700 ℃时，两相的体积分数之差显著增大，镀层仍有残存的非晶相；在400~500 ℃之间形成的Ni3P的晶粒尺寸大于Ni的；温度为500~700 ℃时，Ni相的尺寸大于Ni3P的，但均未超过纳米级。镀层晶格应变表现为随退火温度的升高而降低，镀态时晶格应变最大。激光晶化处理的非晶态Ni-W-P镀层的显微结构特征介于400~500 ℃之间退火的镀层晶化特征。随扫描速度增加，不仅Ni3P晶粒尺寸增大，而且两相的尺寸差变大。
关键字: 激光晶化；退火晶化；化学沉积Ni-W-P；晶化程度；晶粒尺寸；晶格应变
（School of Mechanical Engineering, Shandong Institute of Light Industry, Ji’nan 250353, China)
(2. Zibo Institute of New Materials, Zibo 255040, China）
Abstract:The evolution of microstructures, in terms of degree of crystallisation, grain size and lattice strain of electroless Ni-W-P coating with high phosphorous (13.3%) content during laser and furnace annealing was investigated by quantitative XRD method and morphological observation of SEM. The results show that, during the annealing crystallization of the amorphous coating, the volume fraction of Ni3P exceeds that of Ni, and the volume fraction difference between the two phases increases remarkably at 700 ℃, but the remaining amorphous phase still exists in the coating. The grain size of Ni3P is larger than that of Ni between 400 ℃ and 500 ℃, the grain size of both phases is reversed above 500−700 ℃ and are in the range of nanoscale. The lattice strain of as-plated deposit is the maximum and decreases with the increase of temperature. The characteristics of microstructures of the coating treated by laser is consistent with the deposit annealed by furnace between 400 ℃ and 500 ℃. The grain size of Ni3P and phases difference increase with the increase of the scanning velocity.
Key words: laser crystallizing; annealing crystallizing; electroless Ni-W-P; crystallisation degree; grain size; lattice strain
