施载方向对定向凝固镍基高温合金高温蠕变行为的影响  

THE EFFECT OF APPLIED STRESS ORIENTATION ON THE HIGH TEMPERATURE CREEP BEHAIOUR OF DIRECTIONALLY SOLIDIFIED NICKEL BASE SUPERALLOY

作　　者：袁超[1] 郭建亭[1] 王铁利[1] 杨洪才[2] 王淑荷[1] 张皓[2] 

机构地区：[1]中国科学院金属研究所,沈阳110015 [2]东北大学材料与冶金学院,沈阳110006

出　　处：《金属学报》1998年第7期689-695,共7页Acta Metallurgica Sinica

摘　　要：研究了施载方向对定向凝固镍基高温合金980℃130—190MPa蠕变及断裂性能的影响结果表明三种取向试样的蠕变曲线相似，稳态蠕变均由位错的攀移过程所控制因蠕变断裂机制不同，纵向试样比横向及倾斜试样表现了高得多的啼变塑性，前者为完全穿晶断裂。The effect of applied stress orientation on the creep and fracture behaviour of a directionally solidified nickel base superalloy at 980 ℃ in the stress range of 130 - 190 MPa has been studied. The results show that the creep curves of three orientation specimens, in which the grain boundaries are oriented longitudinally, transversely, and 45° to the applied stress axis, have the same shape. In terms of Dorn creep law, three orientation specimens have same creep mechanism, which is controlled by the dislocation climb process. The strain to fracture in longitudinal specimens is much higher than that in transverse and inclined specimens, the reason is the change of creep fracture mechanism from the transgranular to intergranular failure mode.

关 键 词：施载方向 定向凝固 镍基 高温合金 高温蠕变 

分 类 号：TG111.8[金属学及工艺—物理冶金] TG132.32[金属学及工艺—金属学]