界面热阻对π型铸件凝固过程温度场的影响  

Effect of thermal resistance at interface on temperature field of solidification process for π-type castings

作　　者：焦壮壮 杨燕[1] 袁训锋[1] 王艺儒 JIAO Zhuangzhuang;YANG Yan;YUAN Xunfeng;WANG Yiru(Shangluo University,Shangluo 726000,Shaanxi China)

机构地区：[1]商洛学院,陕西商洛726000

出　　处：《中国铸造装备与技术》2018年第5期24-29,共6页China Foundry Machinery & Technology

基　　金：商洛市科技局科研计划资助项目(SK2017-46);2015年度国家级大学生创新训练项目(201511396717);陕西省高教学会高等教育研究资助项目(XGH17169)

摘　　要：采用直接差分法求解热传导方程,对π型镁合金铸件凝固过程温度场进行模拟,研究界面热阻对温度分布的影响。结果表明:不同铸件/铸型热阻条件下,内外拐角处的温度先快速升高到极大值,随后缓慢减小趋于稳定。随着铸件/铸型热阻的增加,冒口部分热扩散层"梯形状"向"矩形状"转变,冒口之间的"U形"低温区域逐渐增大;随着铸型/空气热阻的增大,底座部分热扩散层增厚,温度逐渐增加;随着铸件/空气热阻的增大,铸件/空气向外传输热量的能力减弱,冒口区域优先凝固的优势减弱直到最终消失。The direct differential method has been used to solve the heat conduction equation. The temperature field of the solidification process for π-type magnesium alloy castings has been simulated, and the influence of thermal resistance at interface on temperature distribution has been studied. The results show that the temperature at the inner and outer corners quickly rises to a maximum value and then slowly decreases to stabilize under different casting / mold thermal resistance conditions. With the increase of the thermal resistance at east/mold, the ＂trapezoid＂ of the heat diffusion layer in the riser changes to the ＂rectangle＂, and the ＂u-shaped＂ low-temperature area between the risers increases gradually. With the increase of the thermal resistance at mold /air, the heat diffusion layer of the base has been thickened while the temperature increases gradually. With the increase of the thermal resistance at east/air, the ability of casting/air to transfer heat outward is reduced, and the advantage of preferential solidification in the riser area is reduced until it finally disappears.

关 键 词：镁合金 温度场 热扩散层 界面热阻 

分 类 号：TG244[金属学及工艺—铸造]