Plastic deformation mechanisms in a crept L12 hardened Co-base superalloy

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:571

Article

Pyczak, F.¹  Bauer, A.²  Goeken, M.²  Neumeier, S.²  Lorenz, U.¹  Oehring, M.¹  Schell, N.¹  Schreyer, A.¹  Stark, A.¹  Symanzik, F.³ 

[1] Ctr Mat & Coastal Res, Helmholtz Zentrum Geesthacht, D-21502 Geesthacht, Germany

[2] Univ Erlangen Nurnberg, Dept Mat Sci & Engn, Inst 1, D-91058 Erlangen, Germany

[3] Helmut Schmidt Univ, D-22008 Hamburg, Germany

关键词: Cobalt based superalloys;    Creep;    Dislocations;    Transmission electron microscopy;    Synchrotron X-ray diffraction;   

DOI  :  10.1016/j.msea.2013.02.007

来源: Elsevier

【 摘 要 】

Plastic deformation mechanisms in a crept L1(2) hardened Co-base superalloy are investigated by transmission electron microscopy. The deformation happens mainly in the cobalt solid solution matrix by slip of ordinary a/2 < 101 > {111} dislocations and rafting of the gamma' precipitates perpendicular to the external compressive stress axis is observed. Dislocation structures are early stages of the development of gamma/gamma' interfacial dislocation networks. Furthermore, gamma' precipitates are sheared by partial dislocations generating stacking faults which sometimes extend over matrix channels and neighbouring gamma' precipitates. Due to the positive lattice mismatch at creep temperature the dislocation activity in matrix channels perpendicular to the compressive external stress axis is less pronounced compared to parallel channels. (C) 2013 Elsevier Ltd. All rights reserved.

【 授权许可】

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