雾化器导液管内径对无铅焊锡粉末形貌及粒度分布的影响

Effect of inner diameter of delivery tube end of atomizer on morphology and size distribution of free-lead solder powder

本试验利用自行设计的超音速雾化制粉装置,研究了导液管内径对SnAgCu系无铅焊锡粉末有效雾化率、粒度分布、球形度及氧含量的影响。研究结果表明:在过热度为250℃,导液管外径为7mm,喷头突出为4 mm,雾化压力为0.7MPa,雾化介质为氮气条件下,导液管内径为3mm,雾化粉末具有最佳的球形度、表面光滑度及粒度分布,同时具有较高的有效雾化率和较低的氧含量;随着导液管内径减小,粉末明显细化,有效雾化率升高,但粒度分布的离散度变大;随着导液管内径增大,粉末有效雾化率急剧降低,粒度分布变差,且表面更粗糙,形状更不规则。

The effects of inner diameter of delivery tube end on the properties such as efficient atomization efficiency, size distribution, sphericity of free-lead solder powder in Sn-Ag-Cu system were investigated. The results show： when inner diameter of delivery tube end is 3.0mm size distribution, surface smoothness and sphericity of free-lead solder power are optimal, the efficient atomization efficiency is higher, and the oxygen content is lower. With the inner diameter of delivery tube end decreasing, the powder is significantly refined and efficient atomization efficiency increases, but size distribution deteriorates. With inner diameter of delivery tube end increasing, efficient atomization efficiency of powder significantly decreases, size distribution deteriorates and powder surface become coarser and more irregular.