激光处理化学沉积Ni-P/Ni-W-P双镀层的显微组织及性能特征

摘要

采用SEM/EDX及XRD定量分析技术研究了化学沉积Ni-P/Ni-W-P双镀层激光晶化前、后的组织特征,并通过表面和截面的硬度测量以及干摩擦磨损实验评估了双镀层的硬度及耐磨性.结果表明,在两种不同的镀液中连续沉积可以制备出Ni-P/Ni-W-P双合金镀层.激光晶化处理后,化学沉积Ni-P/Ni-W-P双镀层表现出外层Ni-W-P比内层Ni-P更高的晶化程度及更大的晶粒尺寸,但外层具有更高的硬度.激光处理的双镀层在给定的加工条件下,其耐磨性优于镀态镀层的.激光处理可直接在空气中进行而不需要氩气保护,这为工业化应用提供了可能性.%Characteristics of microstructures of electroless Ni-P/Ni-W-P duplex coatings were investigated using SEM/EDX and XRD analysis techniques.Microhardness and wear behaviour of the coatings before and after laser crystallization were evaluated by measurements of hardnesses of coating surface and cross-section,and by unlubricated friction and wear experiments.The results indicate that it is possible to prepare electroless Ni-P/Ni-W-P duplex coatings by sequential immersion in two different plating baths.After laser crystallization,the microstructures of electroless Ni-P/Ni-W-P duplex coatings present the characteristics of higher degree of crystallization and larger grain size for outer layer Ni-W-P than inner Ni-P,but outer layer has a higher hardness.The wear resistance of laser-treated duplex coatings in a given process parameter conditions is superior to the as-plated ones.Laser treatment was performed directly in air without argon protection,which provides the possibility for application of industrialized production.