基于单分散逐液滴雾化法制备锡合金微细球形金属粉末

Preparation of tin alloys spherical fine metalpowders by centrifugal atomization based on mono-sized droplets

提出了一种新型微细球形金属粉末的制备方法——单分散逐液滴雾化法。该方法将脉冲微孔喷射系统与离心雾化系统相结合,并对离心雾化系统进行重新设计,利用脉冲微孔喷射系统制备单分散液滴,再将液滴逐滴离心雾化,制得的粉末表面光滑、粒度小、粒度分布窄、球形度高、无卫星粉。利用该方法制备微细Sn63Pb37,Sn0.3AgCu合金粉末,研究转盘加热处理、不同转盘材料(Cu、Ni、304不锈钢)对粉末制备的影响,分析粒径实验值与理论值的差别,讨论雾化过程中液膜的分裂模式。研究结果表明,转盘加热处理可以使得转盘液膜变薄,粉末粒度细化。转盘与金属材料间的润湿性越好,制备的粉末平均粒度越小,且实验值均小于理论值,铜转盘制备的粉末平均粒径最小为24.0μm。液膜分裂模式与润湿性相关,铜转盘显示滴状分裂,镍转盘显示膜状分裂,不锈钢转盘没有发生液膜分裂。

A novel hybrid method for the production of spherical fine metal powders by centrifugal atomization based on mono-sized droplets was proposed.In this method,the mono-sized droplets were prepared by pulsated orifice ejected system,and then the droplets were atomized by centrifugal atomization.The powders with smooth surface,small particle size,narrow particle size distribution,high spherical degree and no satellite powders were prepared by this method.Fine Sn63Pb37,Sn0.3AgCu powders were prepared by this method.The effects of heated treatment on rotation disk and different disk materials Cu,Ni,304 stainless steel on the preparation of the powders were studied,the difference between the experimental value and the theoretical value of particle size was analyzed,and the disintegration mode of liquid film in atomization process was discussed.The results show that the liquid film on the rotation disk tends to be thin and the average particle size of powders can be refined by heating the rotation disk.The better the wettability between the rotation disk and the metal material,the smaller the average particle size of the powders obtained,and the theoretical value of powders is higher than the experimental value,the smallest average particle size of the powders is 21.0μm prepared by copper rotation disk.The mode of liquid disintegration in this method is related to the wettability between the rotation disk and the metal material,the copper rotation disk shows direct droplets disintegration,the nickel rotation disk shows film disintegration,the 304 steel rotation disk does not show liquid disintegration.