Anisotropy of Stress Rupture Property of Ni Base Single Crystal Superalloy DD432
Ni base superalloys have been extensively used in advanced aeroengine.With the devel-opment of modern aviation industry,high demands are being placed on the comprehensive performance of Ni base superalloys at high temperatures.To meet this demand,numerous refractory alloy elements are added to Ni base superalloys.However,in this way,the temperature bearing capacity of the alloy is enhanced,while the microstructure stability is reduced.Therefore,some scholars proposed to develop single crystal blades with various orientations through the anisotropy of a single crystal alloy.The stress rupture anisotropies of a Ni base single crystal superalloy DD432 under 760℃,810 MPa and 1000℃,280 MPa have been investigated in this study.The stress rupture properties of Ni base single crystal su-peralloy DD432 that deviated from<001>,<011>,and<111>with certain degrees were measured.It is discovered that rafting does not occur in specimens with three orientations,and the stress rupture life an-isotropy of specimens is visible at 760℃ and 810 MPa.Furthermore,the stress rupture life of specimens with<111>orientation is the best,and as the orientation deviation degree increases,the stress rupture life gradually decreases.The stress rupture property of specimens with<001>orientation is lower than that of specimens with<111>orientation,and the stress rupture life increases with increasing orientation deviation degree.The creep resistance of specimens with<011>orientation is the lowest,and the stress rupture property is also enhanced as the orientation deviation degree increases.Rafting occurred in all the specimens with three orientations under the conditions of 1000℃ and 280 MPa,and the stress rup-ture property anisotropy of specimens decreased,but still existed.The stress rupture property of speci-mens with<111>orientation was slightly better than that of specimens with<001>orientation,and the stress rupture property of specimens with<011>orientation was still the worst,although it improved.A dif-ference still exists in the stress rupture life as the degree of orientation deviation changes.However,there is no visible linear tendency.
Ni base single crystal superalloystress rupture propertyanisotropy
万方数据
维普
