|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Gamma (FCC)/Gamma-Prime (L12) Co-Based Superalloys II
||Analyzing the Tension/Compression Asymmetry in Creep Deformed Single Crystal Co-base Superalloys
||Malte Lenz, Yolita Eggeler, Christopher Zenk, Steffen Neumeier, Mathias Göken, Philip Wollgramm, Gunther Eggeler, Erdmann Spiecker
|On-Site Speaker (Planned)
In the present work a new Co-based superalloy (ERBOCo-1) was creep deformed in tension and compression under a stress of 400 MPa along the -direction at 850 °C. Tests were interrupted at 0.3 % and 5 % plastic strain and show a pronounced tension/compression asymmetry regarding the total creep times and the minimal creep rates. To obtain a better understanding of the underlying fundamental mechanisms CTEM, HRTEM and LACBED investigations have been carried out. In the early stages of creep, EM analysis reveals different predominant deformation mechanisms for tensile and compressive testing. In tension a planar fault configuration consisting of a superlattice intrinsic stacking fault enclosed by anti-phase boundaries is formed by glide of two loosely coupled superpartial dislocations.
In contrast, compressively deformed samples exhibit pronounced channel dislocation networks and SF in γ’-precipitates and occasionally γ-channels, indicating glide of single partials. I acknowledge DFG&CENEM for financial support.