Ti-Al-Zr-Sn-Mo-Si-Y合金高温塑性变形行为及加工图

Hot Plastic Deformation and the Processing Map of Ti-Al-Zr-Sn-Mo-Si-Y Alloy

在Gleeble-1500热模拟试验机上对Ti-Al-Zr-Sn—Mo—Si—Y合金进行了热压缩试验，采用动态材料模型建立的加工图研究了在变形温度800～1100℃，变形速率在0．002～10s^-1范围内的热变形行为。结果表明：该合金的功率耗散效率的峰值区为875～925℃，应变速率为0．001-0．002s^-1，峰值效率为85％。在温度为900～1000℃，应变速率为0．1～3s^-1的区域和850～950℃，应变速率为0．001-0．01s^-1的环形区域内进行等温压缩，Ti-Al-Zr-Sn-Mo-Si—Y合金发生了动态再结晶，其功率耗散效率为40％～55％。在800～925℃，应变速率为0．03～10s^-1和温度为860～930℃，应变速率为0．003～0．03s^-1区域内易产生流变失稳现象。

The hot deformation behaviors of Ti-Al-Zr-Sn-Mo-Si-Y alloy in the temperature range of 800-1100 ℃ and the strain rate range of 0.001 s^-1 to 10 s^-1 have been studied by using hot compressing testing on Gleeble-1500 stimulator. A processing map is developed on the basis of these data by using the principles of dynamic material modeling. The map exhibits that the deformation at 875-925 ℃ and 0.001 -0.002 s^-1 is the peak efficiency of power dissipation of 85%. Optical microscope observations show that they represent two dynamic recrystallization domains： one at the temperature of 900-1000 ℃ and the strain rate of 0.1 s^-1 to 3 s^-1, the other at the temperature of 850-950 ℃ and the strain rate of 0.001 s^-1 to 0.01 s^-1, and the corresponding efficiency of power dissipation is about 40%-55%. The flow instability regimes appear at two different regimes： at the temperature of 800-925 ℃ and the strain rate of 0.03 s^-1 to 10 s^-1, as well as at the temperature of 860-930 ℃ and the strain rate of 0.003 -0.03 s^-1.