Study on the Short-term Aging Behavior of GH199 Alloy

Short-term aging behavior of GH199 alloy was investigated at 650-1000℃ for 1-24h by using transmission electron microscopy(TEM) and ball hardness test.The results showed that the γ′phase was evolved gradually from ellipse to spherical shape to quadrate during aging treatment and the γ′phase size increased with the increase of aging time.The alloy hardness increased rapidly and then it was invariable gradually with the increase of aging time during the aging treatment at 700-800℃,but the alloy hardness increased rapidly and then it descended gradually with the increase of aging time during the aging treatment at 850-1000℃.The maximum of HB388 was obtained at 800℃,the time,which the peak value of the alloy hardness was reached,would be shortened from 8h to 2h with the increase of aging temperature.