摘要
高温合金涡轮叶片的缘板部分存在横截面的突然扩展,造成定向凝固过程中极易产生杂晶缺陷.本文以自主研发的M4706DS合金作为研究材料,采用Bridgman定向凝固技术制备某单晶叶片,并通过Procast数值模拟软件分析定向凝固过程中叶片缘板处温度场的分布及过冷区域的形成,预测叶片缘板产生杂晶的可能性,模拟结果显示通过降低缘板部分的抽拉速率,可以有效地降低缘板处过冷度,从而减少杂晶形成,这与定向凝固实验结果吻合良好.
The abrupt expansion of the superalloy turbine blade platform resulted in stray gains during directional solidification. A sort of single crystal blades were prepared by Bridgman directional solidification process with home-developed superalloy M4706DS. Besides that, Procast software was used to predict stray grains defect by simulating the distribution of temperature field and the formation of undercooling section at platforms. The simulation results showed that by reducing the withdraw rate of the platform, the udercooling degree of platform can be effectively reduced, and stray grain defects can be reduced, which was in good agreement with the experimental results of directional solidification.
作者
王海洋
张琼元
李林蓄
马德新
杨照宏
曾洪
Wang Haiyang;Zhang Qiongyuan;Li Linxu;Ma Dexin;Yang Zhaohong;Zeng Hong(State Key Laboratory of Long-life High Temperature Materials,Dongfang Turine Co.,Ltd.,Deyang Sichuan,618000)
出处
《东方汽轮机》
2019年第3期47-49,68,共4页
Dongfang Turbine
关键词
数值模拟
单晶叶片
杂晶
定向凝固
numerical simulation
single crystal blade
stray grain
directional solidification
