单晶高温合金HRS定向凝固过程凝固参数的计算机检测与分析

Computer Detection and Analysis of Solidification Parameters During HRS Directional Solidification of Single Crystal Superalloys

建立了一套炉前计算机数据自动采集和控制系统 ,该系统可对HRS定向凝固过程的温度数据进行自动采集。对单晶高温合金DD98定向凝固过程温度场的现场测定和分析的结果表明 :该系统现场采集的数据平稳 ,较好地解决了干扰问题 ;在恒定的加热温度和抽拉速率下 ,温度梯度、糊状区宽度等凝固参数是不断变化的 ,起始端的温度梯度最高 ,凝固后期温度梯度趋于平稳 ,糊状区的宽度随着凝固的进行呈增加的趋势。

A computer automatic data acquisition and control system which can be used for data acquisition and reduction of temperature field during high rate directional solidification(HRS) process has been developed. The system has been applied to the investigation of DD98 single crystal superalloy solidification process. The result shows that the data are stable and the problem of interference at workshop is resolved, the solidification parameters, such as temperature gradient, width of mushy zone, are variable with the stationary heating temperature and withdrawal rate. The temperature gradient is highest in the starting stage and becomes stable during the late stage of solidification. The width of mush zone is increased in the solidification process.