镧元素对石英光纤表面化学镀Ni-P-B涂层上电镀厚镍的影响

Effects of Lanthanum Oxide on Nickel Electrodeposition on Ni-P-B Coating Electroless-plated on Quartz Optical Fiber

在普通瓦特电镀液中添加稀土镧元素在石英光纤表面化学镀Ni-P-B涂层上续镀厚镍。考察了氧化镧对镍沉积速率、电流效率、镀层组成、晶粒尺寸、组织结构以及其它物理性能的影响。用扫描电镜观察镀层表面和断面形貌,用能谱仪和等离子发射光谱仪测定镀层元素和组成。结果表明,在瓦特镀液中添加质量浓度为0.9g.-1的La2O3后,镍沉积速率、电流效率、致密度和硬度分别由15μm.h-1、91.33%、94%和283HV提高至16.2μm.h-1、98.88%、98%和334HV;镀层(约厚840μm)平均晶粒尺寸减小7～8倍;电阻率和可焊性分别由26μΩ.cm和5s～6s降至21μΩ.cm和2s～3s;镀层经热震试验后无起泡或脱落现象。

Lanthanum was added into the common Watt bath to make a thick nickel on the Ni-P-B coating of the quartz optical fiber surface.The influences of lanthanum on nickel deposition rate,current efficiency,coating composition,particle size,structure and other physical properties of the nickel coating were investigated.Scanning electron microscopy was used to characterize the morphologies of nickel coating （surface and cross-section）.Spectroscopy and plasma emission spectroscopy were employed to measure the elements and composition of the nickel coatings.The results show that after the addition of lanthanum oxide with concentration of 0.9 g/L in the Watt bath,the nickel deposition rate,current efficiency,degree of densification and hardness of the Ni-P-B are increased from 15μm/h,91.33%,94% and 283HV to 16.2 μm/h,98.88%,98% and 334HV,respectively;the average particle size of the coating （about 840μm of thickness） is 7～8 times less than that of the coating without adding lanthanum oxide;the resistivity and wetting time are reduced from 26 μΩ·cm and 5～6s to 21 μΩ ·cm and 2 ～ 3s,respectively;there is no blistering and peeling of the prepared coating after thermal shock test.