Short fatigue cracks nucleation and growth in lean duplex stainless steel LDX 2101

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

卷:615

Article

Strubbia, R.¹  Herenu, S.¹  Alvarez-Armas, I.¹  Krupp, U.² 

[1] Univ Nacl Rosario, CONICET, Inst Fis Rosario, RA-2000 Rosario, Santa Fe, Argentina

[2] Univ Appl Sci Osnabruck, Fac Engn & Comp Sci, Osnabruck, Germany

关键词: Duplex stainless steel;    Fatigue;    Crack nucleation and growth;    Microstructure;    EBSD;   

DOI  :  10.1016/j.msea.2014.07.076

来源: Elsevier

【 摘 要 】

This work is focused on the fatigue damage of lean duplex stainless steels (LDSSs) LDX 2101. Special interest is placed on analyzing short fatigue crack behavior. In this sense, short crack initiation and growth during low cycle fatigue (LCF) and short crack nucleation during high cycle fatigue (HCF) of this LOSS have been studied. The active slip systems and their associated Schmid factors (SF) are determined using electron backscattered diffraction (EBSD). Additionally, the dislocation structure developed during cycling is observed by transmission electron microscopy (TEM). Regardless of the fatigue regime, LCF and HCF, short cracks nucleate along intrusion/extrusions in ferritic grains. Moreover, during the LCF phase boundaries decelerate short crack propagation. These results are rationalized by the hardness of the constitutive phases and the dependence of screw dislocation mobility in the ferrite phase on strain rate and stress amplitude. (C) 2014 Elsevier B.V. All rights

【 授权许可】

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