功率超声对A356合金除气效果的影响  

Effect of Ultrasonic Vibration on Degassing of A356 Alloy

作　　者：石婷[1] 张忠涛[1] 张宇博[1] 卢一平[1] 李廷举[1] 

机构地区：[1]大连理工大学材料科学与工程学院,辽宁大连116023

出　　处：《铸造》2010年第6期546-548,共3页Foundry

基　　金：国家自然科学基金资助项目(50874022)

摘　　要：气孔和针孔等缺陷会对铝合金的性能产生不利影响,因此必须采取适当措施减少铝合金中气体的含量,提高产品质量。文中利用真空减压试验,研究不同功率超声作用时间对A356合金除气效果的影响规律。试验结果表明,随着超声作用时间的增加铝合金铸锭内的气体含量明显减少,致密度大幅提高;功率超声作用120s时,熔体内部就不会产生针孔等缺陷;作用时间超过120s后,随着超声作用时间的进一步增加,铝熔体中气体含量变化不明显。通过水模拟试验观察气泡在超声场作用下的运动情况并探讨超声场去除铝合金中气体的机理,功率超声的空化效应和声流效应是实现金属液除气的主要原因。The presence of porosity is detrimental to the properties of aluminum alloy. So it is critical to take effective steps to reduce the gas content in AI alloy, thereby improving the quality of products. In this paper, the effect of ultrasonic action time on degassing of A356 aluminum alloy was studied by using of vacuum decompress test. The results indicate that the gas content decreased obviously with the ultrasonic action time, and the density had a substantial increase. Degassing results were evident within 120 s while the ultrasonic vibrations had little effect on the degassing after 120 s. The movement of bubbles under the action of ultrasonic field was observed by means of the water simulation. The principle of ultrasonic degassing was discussed. Cavitation effects and acoustic streaming were the main mechanisms for ultrasonic degassing.

关 键 词：A356合金 功率超声 除气 真空减压 空化 声流 

分 类 号：TG292[金属学及工艺—铸造]