定向凝固法制备单晶高温合金一次枝晶间距研究  

Primary Dendrite Spacing in Single Crystal Superalloy Prepared by Directional Solidification

作　　者：张小丽[1] 杨亚楠 刘贵群 耿桂宏[1] 杨铠丞 李宝青 

机构地区：[1]北方民族大学材料科学与工程学院,宁夏银川750021

出　　处：《铸造技术》2018年第1期21-24,共4页Foundry Technology

基　　金：北方民族大学国家级大学生创新训练计划资助项目(201611407005);北方民族大学校级重点科研项目资助(2015KJ22)

摘　　要：利用定向凝固技术和籽晶法相结合的方式制备了DD5单晶高温合金。通过正方形估算法和直接测量法研究了DD5单晶高温合金的不同凝固距离(50、150和250 mm)横截面样品的一次枝晶间距。结果表明,随着凝固距离的增大,DD5单晶高温合金的一次枝晶间距逐渐增大;正方形估算法和直接测量法统计的DD5单晶高温合金的平均一次枝晶间距差距不明显,说明正方形估算法的精确度较高,为了提高效率可以采用正方形估算法统计单晶高温合金的一次枝晶间距;不同凝固距离横截面的一次枝晶间距上限约为下限的6倍。The DD5 single crystal supemlloy was prepared by directional solidification and seeding. The square calculation and direct measurement were used to study the primary dendrite spacing of DD5 single crystal superalloy at different solidification distances （50, 150 and 250 mm）. The results show that as the solidification distance increases, the primary dendrite spacing gradually enlarges. In addition, the primary dendrite spacing calculated by square calculation and direct measurement are similar, which indicates the high precision of square calculation. Although the precision of primary dendrite spacing calculated by direct measurement is the most accurate, the method is time-consuming and laborious. In order to improve the efficiency, the square calculation method is used to calculate the primary dendrite spacing of single crystal superalloy. At different solidification distances, the maximum values of the primary dendrite spacings are six times than minimum ones.

关 键 词：定向凝固 籽晶法 单晶高温合金 一次枝晶间距 

分 类 号：TG244[金属学及工艺—铸造]