| The electroless plating technology has been progressed constantly and paid more attention to as one of the ways of surface hardening . In ths paper , We focus on the eletroless Ni alloy plating in the composition , the position rate technologic parameters N the surface heat treatment the thermal stability and so on .The main experiwents and theis results of conclusion are as follows:1. The electroless Ni-P coatings with different Cu content have been deposited fromalkaline bath . The surface morphology icrostructure and crystallization behaviour of the electroless and crystallization behaviour of the electroless Ni-Cu-P alloys have been studied Icy SEM. The results show that the concentration of CuSO4 . 5H2O in the bath has a great offeet on the composition of the deposits the deposition rate , The codeposition of a small amount of Cu makes the crystal grains of the deposits become smaller ,but with the Cu content increasing , the deposits exhibit a larger grain size and a more coarse surface morphology . The thermal statility of Ni-Cu-P deposit increase with the Cu content increasing in the deposits .2. A techniguec of tlectroless Ni-B alloy plating in acidic solution is introduced , which is characterzed ley excellent stability of the plating solution and high deposotion rate . The effects of the composition of the plating solution and technologic parametes on the deposition rate are discussed . The result shows that the Ni-B composition coatings have good aclhension , Very have microhardmess and excellent wear resistance after being tneated at certain temperatures .3. The as plating microstructure of coating is confirmed to be a mixture of amorphous and supersaturated solid solution with XRD analysis . The transformation process of the coating microstructure depends on heat-treatment temperature ,and 350 ℃ is the critical temperature of microstructure trans for mation . It is foud that Ni2B is formed during this trans for mation process , The factors which influence on hardness of coating are evolution of stress , dissolution of B and formation of NiaB and Ni2B. and the formation of Ni2B is the key factor . The peaks of micrt-hardness curves varywith heat-treatment temperatures . The transformation process becomes complex when the heat-treatment temperature accesses crystallizing temperature.5. The Ni-In-B alloy electrodes were prepared by electro less-deposition at Ph=9, t=55 ± 1℃ when the catalysts were added coutinously ,and the electrolessdeposited a lloys are silver bright and compact . Chang the the composition ,pH and the temperature of the bath, and the law of the depositions were studied . The catalytic property of the alloy at electrodes in hydrogen evolution reation in 1 mol/L KOH solution was studied by three electnods stystem . The resuts indicated that Ni-In-B alloy electrodes showed the hightest catalytic property on the certain condition.6. Ni, Co, In, B, deposit on the ion surface and the alloy electrode is obstained via eledrolessdeposit when catalyzed . At room temperature ,the alloy electrode is dipped in the solution of I M NaOH and the corrent and electromotive force is measaureal , then compare it with the ion's .The experiment proved the Ni-Co-In-B amorphous alloy be prepared at 60± and under pH=8.5~9.0 and the alloy has a good ability of gydrogen evlotution Catalyst when current values varied in certain scope.
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