论文部分内容阅读
利用超声变幅杆在7A09铝合金连续铸造过程中进行超声处理,通过Olympus dsx500光学显微镜来观察施加超声处理和不施加超声处理的铝合金表面中缺陷的变化,由此来研究超声铸造对铝合金中微观缺陷的影响。结果表明,相对于未施加超声处理的铸锭,施加超声后铸锭的氧化夹杂缺陷减少,可观察到表面气孔、缩孔缺陷数量上有所增加(从2 912增大为3 436),但是平均尺寸由10.0μm降为7.4μm、缺陷平均面积由0.40mm~2降为0.36mm~2。最后,对超声作用下氧化夹杂、双层膜、晶粒尺寸等对铝合金铸锭中微观缺陷的影响以及相关的作用机理进行了讨论。
Ultrasonic horn was used in the continuous casting process of 7A09 aluminum alloy, the changes of defects on the surface of aluminum alloy with or without ultrasonic treatment were observed by Olympus dsx500 optical microscope, The impact of microscopic defects. The results show that the number of surface pores and shrinkage defects is increased (from 2312 to 3 436), but the number of inclusions in the ingot after the ultrasonic treatment is reduced compared with that of the ingot without ultrasonic treatment. The average size decreased from 10.0μm to 7.4μm, and the average defect area decreased from 0.40mm ~ 2 to 0.36mm ~ 2. Finally, the effects of ultrasonic inclusions, bilayer films and grain size on microscopic defects in aluminum alloy ingots and the related mechanism were discussed.