Nickel Package Cu Composite Powder Preparation Process Of Powder Metallurgy Behavior

In the article, some nickel coated copper powders were prepared by choosing two means ,such as electroplating , electroless plating. Hypophosphite and hydrazine acted as reducing angents respectively when nickel coated copper powders were prepared by electroless plating. The article mainly reserched the processes of preparing nickel coated copper powders by electroplating , electroless plating. The article mainly emphasized on studing the processes of preparing nickel coated copper powders by electroless plating with hydrazine reduction. Six main trial parameters were choosed to design L₂5(5⁶) orthogonal arrays experiment, such as vitriolic nickel concentration, hydrazine concentration, PH value, temperature, keeping-temperature time and the amount of copper powder. The effect on nickle plating on the copper powders was studied and chemical and process properties of pure nickel-coated copper powder were analyzed. Through molding and sintering nickel-coated copper powders, the article studied the behavior of powder metallurgy. All these study results were followed.Some nickel-coated copper powders were prepared by electroplating with nickle board and nickle net as cathodes. Trials results showed: nickle could plate on the copper powders by electroplating, and nickle net as cathode could enhance adsorption area, which would improve uniformity of nickle-coat. EDS and XRD analysis showed that the coating of composite powders was continuous,and was made of pure nickel.Some nickel coated copper powders were prepared by electroless plating with hypophosphite reduction. The results showed: with hypophosphite, the nickle could well plated on copper powders activited and acidified by HC1 solution instead of expensive PdCl₂, The morpho of composite powders were observed by SEM, and the results showed the surface of composite powder was coarse, XRD and EDS analysis showed that the coating was made of Ni- P alloy.Some nickel coated copper powders were prepared by electroless plating with hydrazine reduction. The results showed: the copper powders could be directly plated on without any activition. Excellent parameters were attainted, such as, vitriolic nickel concentration: 30g/L, hydrazine concentration:70ml/L, PH value:13, temperature: 82°C, and the amount of copper powder: 15g/L, keeping temperature time:35min. Pure nickel-coated copper powder could be prepared through excellent parameters. The morpho of composite powder was observed by SEM, and the result showed the surface of composite powder was coarse. EDS and XRD analysis showed that the coating of composite powders was made of pure nickel. Chemical composition of composite powders were measured, and the results showed composite powders were agreed with powder metallurgy, and the carbon content and the hydrogon loss of composite powder were decreased with hydrogon reducing. EDS and XRD showed when sinteringtemperaturewas 800 °C, crystal degree of nickel-coated copper powder metallurgy was more increased and structure of Ni-Cu alloy was more uniformity.