摘要
在半连续铸造过程中施加超声制备了ф1250 mm 2219铝合金大规格铸锭。利用光学显微镜、扫描电镜、电子万能试验机等仪器对常规铸锭和超声铸锭的微观组织与力学性能进行了检测与分析,探究超声作用的内在机制。结果表明：超声振动明显细化晶粒,减小截面上的晶粒尺寸不均匀性;改善组织形态,心部粗大的柱状晶转变为细小的球状等轴晶;有效抑制了晶内第二相的聚集和长大,使其呈均匀密集点状析出。超声不仅能有效提高铸锭各位置的综合力学性能,还能改善铸锭截面的力学均匀性。
The 2219 large-scale aluminum alloy ingot with diameter of 1250 mm was prepared by applying ultrasomc m the process of semi continuous casting process. The microstructure and mechanical properties of the conventional ingot and ultrasonic casting ingot were tested and analyzed by using optical microscope, scanning electron microscope, and electronic universal testing machine, and the mechanism of ultrasonic treatment was analyzed. The result shows that the ultrasonic vibration obviously refines the grain, decreases the inhomogeneity of grain size in cross section, and improves microstructure; the coarse columnar crystals in the center changes into small globular ~quiaxed grains. It effectively inhibits the aggregation and growth of the second phase in the crystal, and the second phase precipitates in form of uniform dense dots. The ultrasonic can not only effectively improve the comprehensive mechanical properties of each position of the ingot, but also improve the mechanical homogeneity of cross section of the ingot.
作者
李昴
李瑞卿
李晓谦
曹飞
LI Mao1,2, LI Ruiqing2,3, LI Xiaoqian1,2,3, CAO Fei1,2(1. School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China; 2.State Key Laboratory of High Performance Complex Manufacturing, Central South University, Changsha 410083, China; 3. Light Alloy Research Institute, Central South University, Changsha 410083, Chin)
出处
《热加工工艺》
CSCD
北大核心
2018年第5期21-24,28,共5页
Hot Working Technology
基金
国家自然科学基金资助项目(51475480
5160496)
关键词
超声场
半连续铸造
力学性能
均匀性
ultrasonic field
semi continuous casting
mechanical properties
homogeneity
