W、P含量对Ni-W-P化学镀层硬度和耐磨性的影响

Effect of W and P on Hardness and Wear Resistance of Ni-W-P Electroless Plating

目的使Ni-W-P合金镀层具有最大的硬度和耐磨性,通过试验寻找镀层中的最优W、P含量。方法通过改变化学镀液中钨酸钠的加入量(0~75 g/L)制备出不同W、P含量的Ni-W-P镀层。用扫描电镜和能谱仪分析镀层中W、P的含量,用显微硬度计测试镀层的硬度,用球盘式摩擦磨损试验机测试镀层的摩擦系数和磨损率。对比分析镀层的硬度与镀层中的W、P含量,研究它们之间的内在关系。通过X射线衍射仪对镀层进行物相分析,探索W、P含量与镀层中典型物相之间的关系,进而分析其与镀层硬度和耐磨性的关系。并用同样的方法研究了时效处理条件下镀层化学成分与镀层硬度、耐磨性之间的关系。结果试验条件下,当P的质量分数低至6%左右时,镀态镀层硬度最大,耐磨性最好。镀层经过400℃×1h时效处理后,当P的质量分数为8.5%左右、W的质量分数为7.5%左右时,镀层有最大的硬度和耐磨性。结论镀态下,镀层的硬度主要随P含量的增大而减小,W含量对其影响不大。时效态下,镀层的硬度主要随W含量的增大而增大,P含量对其影响不大。

The work aims to make Ni-W-P alloy plating possess the greatest hardness and wear resistance and find out the optimum contents of W and P in plating through test. Ni-W-P electroless plating with different W and P contents were prepared by changing the addition amount of sodium tungstate（0-75 g/L） in electroless plating bath. Contents of W and P were analyzed by SEM and EDS, hardness of plating was tested by microhardness tester and friction factor and wear rate of plating were de-tected by plating ball-plate friction and wear tester. Hardness of plating and contents of W and P in plating were analyzed by contrast to study the internal relation. X-ray diffractometer was used to analyze the phase of plating to detect the relation between contents of W and P and typical phase in plating so as to study the relation between phase and plating harness and wear resistance. The same method was adopted to investigate the relation between chemical compositions, hardness and wear resistance of plating at aging treatment condition. At test condition, when mass fraction of P reached about 6%, the plating at plating condition had the greatest hardness and the best wear resistance. After aging treatment for 1 h at 400 ℃, fraction mass of P and W respectively reached about 8.5% and 7.5% and plating had the largest hardness and wear resistance. At plating condition, the hardness of plating decreases as the content of P increases, but the effect of W on the hardness is minor. At aging treatment, the hardness of plating can increase as the content of W improves, but the effect of P on the harness is minor.