化学法制取RE—Ni—B—Al_2O_3复合镀层及其性能研究

Electroless RE Ni B Al_2O_3 Composite Psating and Film Properties

提出ＲＥ—Ｎｉ—Ｂ—Ａｌ２Ｏ３化学复合镀溶液和工艺条件，以获得Ｂ４．８ｗｔ％、ＲＥ０．４５Ｗｔ％、Ａｌ２Ｏ３６．２ｗｔ％的复合镀层。分析镀液中ＲＥ（稀土）、Ａｌ２Ｏ３浓度、搅拌速度、温度对镀速、复合镀层Ａｌ２Ｏ３共析量、硬度和耐磨性的影响。使用Ｘ射线衍射仪和扫描电镜观察镀层微观形貌。稀土的加入可以提高晶化温度和镀层性能。在热处理中复合镀层晶变过程为非晶态－混晶态－晶态，在３５０℃、５００℃热处理１ｈ，复合镀层硬度、耐磨性分别达到最佳值。

An electroless plating process is Provided to obtain RE-Ni-B-Al2O3 composite containing (in wt%) B 4.8, RE 0.45 and Al2O3 6.2. Effects of RE(rare earth) and Al2O3 concerntration, agitation and working temperature of the bath on deposition rate, Al2O3 content in the film are studied. Micromorphology of the composite is investigated by means of X-ray diffraction and scanning .electron microscope.Addition of RE may increase crystallizing temperature and improve film properties. Crystallization of the composite during heat treatment proceeds from the state of amorphous through mixture to crystal. Optimum hardness and wear resistance of the deposit may be obtained by heat treatment at 350 ℃ and 500 ℃ respectively for l hour.