Study on the Dispersing Technique of Nanometer CoCrMo Composite Powders in Water Solvent

On the basis of Zeta value measurement of the nanometer CoCrMo composite powders prepared by DC arc plasma evaporation,the influences of supersonic dispersing time and surfactant concentration on the dispersing properties in water solvent were systematically studied for the nanometer CoCrMo composite powders by using polyvinylpirrolidone(PVP),triethanolamine(TEA),Cetyl Trimethyl Ammonium Bromide(CTAB),Secretary Ban-80(STAN-80),Sodium Hexametaphosphate(SHMP) as surfactants.The results show that(1) Nanometer CoCrMo composite powders at different pH,water solvent with a negative charge,its maximum value of Zeta potential locations in pH=9;(2) Ultrasonic time and the amount of dispersant significant affects on the dispersion effect.With the increasing of ultrasonic dispersing time and the concentration of surfactant,the dispersion property of the suspension increased,then decreased again after arrived a maximum;(3) SHMP have better effect on dispersing property of nanometer CoCrMo composite powders.The effect of surfactants using in the experiment on the dispersion property from high to low order in turn is: SHMP,STAN-80,CTAB,PVP,TEA.The optimum dispersion condition was proposed as follows: pH value is 7.4,3%(wt.) SHMP with 20 min.ultrasonic dispersing time and 560 W ultrasonic power.