熔体保温条件下溶质Si含量对超声波处理铝合金凝固组织的影响  

Effect of silicon solute contents on solidification structure of aluminum alloy ingots by ultrasonic treatment under melt holding

作　　者：贾征[1] 李军文[1] 姜峰[1] 尹铁生[1] 杨旭光[1] 付莹[1] 赵阳[1] 

机构地区：[1]辽宁工业大学材料与化学工程学院金属超声凝固研究室,辽宁锦州121001

出　　处：《轻合金加工技术》2009年第8期9-12,共4页Light Alloy Fabrication Technology

基　　金：教育部留学回国人员科研启动基金资助项目(20071067);辽宁省教育厅创新团队项目(20081224);辽宁省自然科学基金资助项目(20082177)

摘　　要：以工业纯铝、Al-2.5%Si合金、Al-5%Si合金以及Al-7%Si合金为对象,分别研究了保温条件下超声波处理对其凝固组织的影响。结果表明,在保温条件下,溶质Si的含量对超声波处理后铸锭的凝固组织有直接的影响。在694℃无超声波处理时,溶质Si含量大的铸锭,等轴晶细小且分布均匀;而在相同条件下进行超声波处理时,随着溶质Si含量的增多,等轴晶区域也随之增大,由于随着溶质Si含量的增多,细小的二次枝晶以及三次枝晶很容易被声流的搅拌作用所分断,并且破碎的枝晶随着这种搅拌作用而被分散到熔体的各处,从而产生了细化效果。另外,由于超声波的空化作用,对纯铝也有一定的细化效果,但是不如对合金的明显。Effect of solidification structure of ultrasonic treatment by using commercially pure aluminum, Al-2.5 % Si alloy, Al-5 % Si alloy and Al-7 % Si alloy was studied under the condition of melt holding. The results indicate contents of silicon have the direct effect on solidification structure of ingot by ultrasonic treatment. The equiaxed grain is refining and uniform distribution which is the ingot of having the maximum silicon contents under the condition of 694℃melt holding and without ultrasonic treatment; however, under the same condition of treating melt, with the increase of silicon contents, the equiaxed grain regions are increase; because of the increase of solute contents, the finer secondary dendritic crystal and tertiary dendritic crystal are easily broken up by the stirring of acoustic streaming, and the broken dendritic crystal is dispersed everywhere in the melt as the stirring, so this can cause the grain to be refined; and the pure aluminum has a effect of a certain refinement because of the cavitation of ultrasound, but its effect is not obviously compared to the alloy.

关 键 词：保温 溶质Si 超声波 铝合金 细化 空化作用 声流效应 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG292[金属学及工艺—金属材料]