Study On NI-P Electroless Plating Additive

In this paper, Electroless Ni-P plating process, Bad bath solution stability of plating agent, low deposition rate in plating bath, bad corrosion resistance of cladding high variance of component part, a high fluctuation of hardness bad densification before and late etc, By using orthogonal-design experiments and contrast experiments, deposition rate porosity of coating and hardness of heat treatment before and late by using dynamiting method. Target of the main examine by according to deposition rate, hardness of coating, porosity of coating and bath solution stability,the main salt NiSO4, The reducing agent NaH2PO2 of electroless plating process of the main technology factors are systemic studied. Concentration proportion of the main salt and the reducing agent and four kinds of complex agent, five kinds of accelerators, six kinds of stabilizers in acid electroless Ni-P plating process' s the laws of effect. Making theoretical basis for application of electroless plating additive, making basis of industry electroless maintaining of electrloless plating. Even of preparation agent, lightness, good corrosion resistance, good hargness, getting result by studying:1 Different effect of different behavior requirement of effecting electroless plating technology and cladding mass. For deposition rate, the main effect for concentration NiSO4 and accelerators; NaH2PO2 concentration effect porosity of coating and hardness; buffering agent and complex agent effect bath solution stability.2 Concentration more effect bath solution stability and cladding behavior. The most importance for NiSO4 and N.H2PO2' s concentration proportion. The best concentration range of NiSO4 · 6H2O is 20~30g/l, concentration of NaH2PO2 · H2O is 25~35g/l. the best mole proportion is 0. 3~0. 5.3 Different kinds of complex agents and use level for bath solution stability of electroless NI-P plating are different effects. In using of mononcomponent complex agents, Lactic acid is better complex agents. Its PH is high and makes an adding deposition rate, a high hardness, and bath solution stability. But proportion lactic acid and lactic acid-citric acid, lactic acid apple make low bath solution stability. A little level the third complex agents butanedioic acid of lactic acid and lactic acid-apple acid getting more higher bath solution stability.4 Metacetonic acid and glycerol is good accelerators of plating bath. Themore metacetonic acid and glycerol' s concentration the higher deposition rate, the less nickel coating. But butanedioic acid and glycolic acid don' t make accelerator of electroless NI-P plating.5 Showing stability by compound component, hypo and potassium iodide, lead sugar, ammonium bifluoride etc is compounded, getting satisfactory effect.6 Because different effect and port of electroless additive in electroless plating process, some of electro less additives is complex agents and is accelerators, but some of complex agent' s the good effect and inhibited deposition rate, so getting the better effect by optimum of electroless planting' s components, the optimum condition 1,2,3 by orthogonal-design experiment in the test. And getting fast depositing velocity, good bath solution stability, surface structure is compact and even, good hardness by using in industry application.