摘要
本研究以一维长杆铸件为对象,采用K型热电偶与数据分析软件研究了亚共晶Al-7Si-0.6Mg合金的凝固变形规律。结果表明:固定体积下,随着铸件模数与长宽比的增加,初晶析出温度与二元共晶反应温度随之上升,第一冷却速度、第二冷却速度与整体凝固冷却速度连续下降;受铸件/铸型界面换热影响,起始凝固部位体积收缩产生气隙并沿边线逐渐向心部区域扩展,凝固温差诱发产生的热应力受铸型刚性约束作用,铸件产生挠曲变形,宽度方向凝固尺寸变形量符合Lorentz数学函数分布,且随铸件长宽比降低逐渐下降,高度方向符合Extreme数学函数分布,随铸件长度增加连续上升;凝固总尺寸变形量随着铸件模数、凝固枝晶搭接温度与时间的增加而连续上升,随着凝固冷却速度与二元共晶反应温度的增加而不断降低。
The solidification law of Al-7Si-0.6Mg alloy was studied by using the K-type thermocouple and data analysis software, one-dimensional long rod castings were chosen as the research object. The results show that the aluminum matrix precipitation and the binary eutectic reaction temperature increase with the incensement of modulus and aspect ratio of the castings, and the first, second and total cooling rates decrease continuously under the fixed volume. Due to the effect of interface heat transfer of casting and mold, the air gap caused by solidification volume shrinkage extends along the edge to the core region. For the thermal stress induced by the solidification temperature difference was restrained by the rigid molds, the casting deform deviously, the size deformation in width direction is in accordance with the Lorentz mathematical function distribution and decreases gradually with the decline of aspect ratio, the height direction obey the Extreme mathematical function distribution and increases continuously with the length size. The total deformation size increases with the addition of modulus, temperature and time of dendrite lap, and decreases with the increase of cooling rate and binary eutectic reaction temperature serially.
作者
樊振中
杨守杰
宫玉辉
韩艾京
郝慧林
米刚
FAN Zhen-zhong;YANG Shou-jie;GONG Yu-hui;HAN Ai-jing;HAO Hui-lin;MI Gang(Beijing Institute of Aeronautical Materials, Beijing 100095, China;Beijing Advanced Engineering Technology and Application Research Center of Aluminum Materials, Beijing 100095, China)
出处
《铸造》
CAS
CSCD
北大核心
2017年第11期1184-1190,共7页
Foundry
基金
中国航空工业集团公司北京航空材料研究院新产品研发基金(KJSC160206)
