小角度晶界对单晶高温合金DD6持久性能的影响

Effects of Low Angle Grain Boundaries on Stress Rupture Properties of Single Crystal Superalloy DD6

在800℃,850℃和900℃的温度条件下,研究小角度晶界对第二代单晶高温合金DD6持久性能的影响。结果表明,带有小角度晶界合金的持久性能低于[001]取向DD6合金的持久性能。并且,随着晶界角度的增加,持久性能具有明显的降低倾向。晶界角度较大时,带有小角度晶界合金的持久性能明显低于[001]取向的性能。晶界角度较小时,与[001]取向相比,800℃温度条件下带有小角度晶界合金的持久性能明显较低;而在850℃和900℃的温度条件下,尽管带有小角度晶界合金的持久性能较低,但数值与[001]取向的性能相差不大,表明随着温度的升高,小角度晶界对持久性能的影响减弱。

The effects of low angle grain boundaries （LABs） on the stress rupture properties of second generation single crystal superalloy DD6 were investigated at 800℃ , 850℃ and 900℃. The stress rupture properties of DD6 with LABs tended to decrease with angle increasing, and were rather low when the angles of LAB were relatively larger. Meanwhile the stress rupture properties of DD6 alloy with [ 001 ] orientation were superior to those of the alloy with LABs. When the angles of LABs were relatively lower, the stress rupture properties of DD6 with LABs were lower than those of the alloy with [001 ] orientation at the condition of 800℃ ; however, the stress rupture properties of DD6 with LABs approached quantitatively to those of the alloy with [ 001 ] orientation at the conditions of 850℃ and 900℃ ,indicating that the effects of LABs on rupture properties decreased with temperature increasing.