液态金属超声雾化喷嘴的气雾化性能影响因素  

Influence factors of gas atomization performance of liquid metal ultrasonic atomizer nozzle

作　　者：周珊 刘明翔[1] 隋大山[1] 崔振山[1] 

机构地区：[1]上海交通大学模具CAD国家工程研究中心,上海200030

出　　处：《粉末冶金材料科学与工程》2017年第4期451-457,共7页Materials Science and Engineering of Powder Metallurgy

基　　金：国家科技重大专项资助项目(2012ZX04012011)

摘　　要：采用Fluent软件建立超声雾化喷嘴气流场的数值模拟模型,研究入口压力、导液管孔径与伸出长度对超声雾化喷嘴气雾化性能的影响,并采用超声雾化法制备GCr15轴承钢粉末,验证入口压力对粉末粒度的影响。结果表明:导液管伸出长度Δh=1 mm时,入口压力越大,越有利于提高雾化效果;在Δh=2 mm或Δh=3 mm条件下,当入口压力小于2.0 MPa时,增大入口压力可有效提高雾化性能,而当入口压力超过2.0 MPa后,增大入口压力对提高雾化性能效果有限。导液管的孔径对气流场结构影响较小,主要通过影响金属液的质量流率来影响雾化效果。雾化实验结果表明,在Δh=1 mm、导液管孔径d=4.5 mm时,2.8 MPa入口压力下的雾化性能优于2.0 MPa与1.2 MPa下的雾化性能,获得的GCr15轴承钢粉末平均粒径最小,整体球形度最佳,该实验结果与数值模拟研究结果一致。A numerical model of ultrasonic gas field was constructed in Fluent to study the effect of inlet pressure, melt orifice diameter and protrusion length of the nozzle on the gas atomization performance, and GCrl5 bearing steel powder was also prepared by ultrasonic gas atomization to validate the effect. The results indicate that a higher inlet pressure will lead to better atomization at protrusion length of 1 ram. At the protrusion length of 2 mm or 3 mm, an increase in inlet pressure will effectively improve the atomization when inlet pressure is less than 2.0 MPa, while further increase will hardly gain better performance when inlet pressure is over 2.0 MPa. The melt orifice diameter shows little effect on the gas field structure but influences the melt mass flow rate which deeply shapes the atomization process. The atomization experiment at the protrusion length of 1 mm and orifice diameter of 4.5 mm shows that the GCrl5 powder produced under the inlet pressure of 2.8 MPa has a smaller mean size and better sphericalness compared with the powder under the inlet pressure of 2.0 MPa or 1.2 MPa, and the experimental results are in accord with that of the numerical simulation.

关 键 词：超声雾化 气流场 入口压力 导液管孔径 伸出长度 GCR15轴承钢 

分 类 号：TF123.2[冶金工程—粉末冶金]