Study On The Metal Texturing Technology Of Composite Electrodeposition

With rapid development of aerospace,automobile manufacturing industry and electronics industry.Requirements to quality of cold-rolled sheet and roll are higher.At present,there are many methods to roughen roll on surface.But there is still insufficient.It is significative to explore a way of roughening which have uniform roughening,high efficiency,wide range of roughness,good wear-resisting performance and long service life.According to current roughening technology at domestic and abroad,the subject adopts a new way of roughening technology at present,it is electrochemical deposition.In the process of electrodeposition,some fluid particles are added to deposition liquid.The codeposition method of nickel deposit and particles are used to increase the roughness of coating.Electroplating chromium is used to enhance roughening layer.The hardness and wear resistance are enhanced.Coating roughness?Ra?,wear resistance and hardness are used as test index to optimize parameter optimization.The impacts of current density,concentration of main salt,pH value,solution temperature,kinds and concentrations of particles on the test results are examined in the experience.Experimental results show that the kind of particles affects result greatly in process of composite electrodeposition.The hardness ranking from good to bad are Ni-Al₂O₃ coating,Ni-ZrO₂,Ni-SiO₂ coating.Texturing results ranking from good to bad are Ni-Al₂O₃ coating,Ni-SiO₂ coating,Ni-ZrO₂ coating.The hardness of composite electric sediments film is enhanced obviously after chrome plating.The mean hardness increase from 461.68 Hv to 660 Hv,the maximum can reach 1049 Hv.The mean roughness decreases from 4.48?m to below 4?m.Coating wear resistance is enhanced after chrome plating,the average wear is reduced by 60%.Coating hardness is higher when pH is 4.2⁵.0,electric current density is 3⁴A·dm^-2,concentration of Al₂O₃ is 8¹2g·L^-1 temperature is 42 ? ⁵2 ? and concentration of NiSO₄ is 230²50g·L^-1,hardness is 660¹049Hv.Coating roughness is higher,when pH is 3.9⁴.3,electric current density is 2.5³.5 A·dm^-2,concentration of Al₂O₃ is 8¹1g·L^-1 temperature is 48 ? ⁵5 ? and concentration of NiSO₄ is 230²50g·L^-1,Ra can reach 2.5³.5?m.Abrasion performance is higher,when pH is 4.0⁴.5,electric current density is 2.5³.5 A·dm^-2,concentration of Al₂O₃ is 4⁸g·L^-1,temperature is 45⁵5? and.The parameters are optimized when concentration of NiSO₄ is 280 g/L,concentration of Al₂O₃ is 10 g/L,electric current density is 3 A·dm^-2,pH is 4.8 and temperature is 45 °C after orthogonal test,hardness reaches 963.7Hv,roughness reaches 3.576?m and abrasion resistance is good.