定向凝固ZMLMC法温度梯度的测定及其对凝固组织的影响  

Determining the Temperature Measurement of Temperature Gradient on ZMLMC Directional Solidification Apparatus and the Effect of Temperature Gradient on Solidification Microstructure

作　　者：张卫国[1] 刘林[1] 黄太文[1] 张聚辉[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《铸造技术》2006年第11期1165-1168,共4页Foundry Technology

基　　金：国家自然科学基金资助项目:50395100;10377012

摘　　要：对定向凝固区域熔化液态金属冷却法的固液界面前沿温度梯度进行了测定。在3mm/min的凝固速率下得到的温度梯度高达813K/cm,并且发现温度梯度随着凝固速率的增加而呈减小趋势。得出这种工艺下一次枝晶间距λ1与工艺参数即温度梯度GL和凝固速率V的对应关系,在此工艺参数下获得良好的定向组织。对试验数据λ1与GL-0.5、V-0.25值进行线性回归,其线性回归关系式为:λ1=-0.0032+0.0655G-0.5V-0.25。The temperature gradient in front of S/L interface was measured on Zone Melting Liquid Metal Cooling（ZMLMC） directional solidification apparatus. The temperature gradient can reach up to 813 K/cm at solidification rate of 3 mm/min. The temperature gradient is found to to reduce with increase of withdrawing speed. The relation between the primary arm spacing λ1 and processing parameter-temperature gradient GL and solidification rate V has been inferred. The preferable directional microstructure is obtained under this process. The test data λ1 and the value of GL^0.5. V^-0.25 have been processed through linear regression, and the relation of linear regression can be expressed as： λ1 = - 0. 0032 ＋ 0. 0655 G^- 0.5 V^- 0.25.

关 键 词：定向凝固 温度梯度 凝固速率 一次枝晶间距 

分 类 号：TG244[金属学及工艺—铸造]