中文摘要：

通过等温恒应变速率压缩试验,研究了2种FGH98合金粉末热等静压锭坯在1 050~1 150℃/0.005~1.000 s-1的变形行为。基于动态材料模型,建立了2种粉末锭坯的热加工图。结果表明,2种粉末锭坯的流变曲线特征相似,同种变形条件下,氩气雾化（AA）粉末锭坯的峰值应力小于等离子旋转电极（PREP）粉末锭坯。AA粉末锭坯的最佳变形窗口为1 088~1 108℃/0.005~0.016 s-1,功率耗散效率η大于42%;PREP粉末锭坯的最佳变形窗口为1 098~1 120℃/0.010~0.016 s-1,η大于40%。

英文摘要：

The hot deformation behavior of as-HIPed PM superalloy FGH98 in the temperature range of 1 050- 1 150 ℃ and strain rate range of 0.005-1.000 s-1 was investigated by using isothermal constant strain rate compressing tests. The powder was prepared with different atomization methods. On the basis of dynamic material modeling, processing maps for the two atomized billet were established. The results show that the rheological curves of the two kinds of billets are similar. Under the same deformation condition, the peak stress of argon gas atomization （AA） powder billet is lower than that of plasma rotating electrode process （PREP） powder billet. The optimum de- formation window forAA powder billet is 1 088-1 108 ℃/0.005-0.016 s-1, the efficiency of power dissipation t/ is higher than 42%. But the optimum deformation window for PREP powder billet is 1 098-1 120 ℃/0.010-0.016 s-1, t/ is higher than 40%.