冷坩埚连续熔铸与定向凝固Ti6Al4V合金的温度场计算  

Temperature Field Calculation on Cold Crucible Continuous Melting and Directional Solidification of Ti6Al4V Alloy

作　　者：陈瑞润[1] 丁宏升[1] 郭景杰[1] 梁富振[1] 张子钦[1] 毕维生[1] 刘林[2] 傅恒志[1] 

机构地区：[1]哈尔滨工业大学先进材料特种凝固加工研究所,黑龙江哈尔滨150001 [2]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《稀有金属材料与工程》2007年第10期1722-1727,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金重大项目(50395102)

摘　　要：为有效利用冷坩埚,更优控制工艺参数,获得冶金质量良好的铸棒,本文对冷坩埚连续熔铸与定向凝固Ti6Al4V温度场进行计算。根据电磁场的感应加热形成上下料棒、电磁压力形成驼峰的情况确定边界条件;采用抛物线逼近确定驼峰形状;对运动单元所处位置的识别实现连铸过程。对功率52kW、速度为3mm/min的条件下进行计算。结果表明,料棒在45s时开始熔化,在70s时形成驼峰,然后熔体获得一定的过热度,形成凝壳,在115s熔体达到最高温度;抽拉过程中上送料能完全熔化,温度场基本稳定,凝固界面的形状和位置基本不变,凝固界面的形状为中间平直、两端上翘,传热基本以轴向传热为主。相同条件下进行实验,实验结果与计算结果相符合,从而证明计算程序在计算冷坩埚连续熔铸与定向凝固温度场是有效的。In order for making efficient use of the cold crucible, optimizing technological parameters and obtaining perfect metallurgy quality billets, the temperature fields of the cold crucible continuous melting and directional solidification of Ti6Al4V have been calculated. Boundary conditions were determined according to the feeding billet and fresh billet formed by induction heating, the meniscus formed by electromagnetic force. The meniscus shape was obtained from the parabola approaching the experimental one. Continuous casting was achieved by distinguishing from the moving unit at different positions. The calculation results under the conditions of 52 kW and 3 mm/min velocity show that the feeding billet begin to melt at 45 s and the meniscus was formed at 70s, then the melt had superheat degree and the skull was formed, the melt reached the highest temperature at 115 s. The feeding billet was melted completely and the temperature field was steady, the shape and the position of solidification front were invariable in the process of continuous melting and directional solidification. The solidification front was planar in the middle but upwarp on both sides, most of heat was transferred in axial direction. Experimental results are agreement with the calculation results, which proves that the procedure is accurate for calculating the temperature field of cold crucible continuous melting and directional solidification.

关 键 词：冷坩埚 定向凝固 温度场 数值计算 

分 类 号：TG292[金属学及工艺—铸造]