Metastability-assisted fatigue behavior in a friction stir processed dual-phase high entropy alloy

ABSTRACT Metastability-based high entropy alloy design opens a new strategic path for designing high-strength materials. However, high strength is always coupled with poor damage tolerance under cyclic loading conditions (fatigue). To overcome this drawback, here we present grain-refined Fe42Mn28Cr15Co10Si5 exhibiting significantly high fatigue strength as compared with leading transformation induced plasticity steels upon friction stir processing. The enhanced fatigue behavior is attributed to the metastability-promoted γ→ϵ transformation that caused local variation in work-hardening activity near the crack tip, and subsequent crack branching. Thus, decreased γ phase stability assisted not only in attaining strength but also in making the alloy fatigue-resistant. GRAPHICAL ABSTRACT Impact Statement Fatigue resistance of dual-phase TRIP Fe42Mn28Cr15Co10Si5 was evaluated. Metastability-promoted γ→ϵ transformation improved fatigue life due to local enhancement in work-hardening near the crack tip.

[1]  S. Suresh.  Fatigue of materials , 1991 .

[2]  Mitsuyuki Kobayashi,et al.  Cyclic deformation behavior of a transformation-induced plasticity-aided dual-phase steel , 1997 .

[3]  W. S. Owen,et al.  The dependence of some tensile and fatigue properties of a dual-phase steel on its microstructure , 1985 .

[4]  H. Maier,et al.  The role of monotonic pre-deformation on the fatigue performance of a high-manganese austenitic TWIP steel , 2009 .

[5]  Rajiv S. Mishra,et al.  Reversed strength-ductility relationship in microstructurally flexible high entropy alloy , 2018, Scripta Materialia.

[6]  H. Gao,et al.  Strain-induced martensitic transformation in fatigue crack tip zone for a high strength steel , 2005 .

[7]  H. Türker,et al.  The effect of martensite content on the fatigue behaviour of a ferritic-martensitic steel , 1990 .

[8]  A. Ly.  The effects of pre-straining conditions on fatigue behavior of a multiphase TRIP steel , 2016 .

[9]  M. Islam,et al.  Tensile and Plane Bending Fatigue Properties of Two TRIP Steels at Room Temperature in the Air—A Comparative Study , 2007 .

[10]  G. B. Olson,et al.  A general mechanism of martensitic nucleation: Part I. General concepts and the FCC → HCP transformation , 1976 .

[11]  R. Mishra,et al.  Extremely high strength and work hardening ability in a metastable high entropy alloy , 2018, Scientific Reports.

[12]  S. S. Nene,et al.  Enhanced strength and ductility in a friction stir processing engineered dual phase high entropy alloy , 2017, Scientific Reports.

[13]  K. Sugimoto,et al.  Fatigue strength of newly developed high-strength low alloy TRIP-aided steels with good hardenability , 2010 .

[14]  K. Manabe,et al.  Effect of Heat Treatment on Microstructure and Mechanical Properties of TRIP Seamless Steel Tube , 2012 .

[15]  Y. Birol.  What happens to the energy input during fatigue crack propagation , 1988 .

[16]  Y. H. Wang,et al.  Enhanced strength and ductility of bulk CoCrFeMnNi high entropy alloy having fully recrystallized ultrafine-grained structure , 2017 .

[17]  Luiz Fernando Martha,et al.  Fatigue life prediction of complex 2D components under mixed-mode variable amplitude loading , 2003 .

[18]  H. Noguchi,et al.  Bone-like crack resistance in hierarchical metastable nanolaminate steels , 2017, Science.

[19]  K. Tsuzaki,et al.  Effect of γ to ε martensitic transformation on low-cycle fatigue behaviour and fatigue microstructure of Fe-15Mn-10Cr-8Ni-xSi austenitic alloys , 2016 .

[20]  K. Tsuzaki,et al.  Effect of alloying composition on low-cycle fatigue properties and microstructure of Fe–30Mn–(6−x)Si–xAl TRIP/TWIP alloys , 2013 .

[21]  L. Zhao,et al.  Fatigue crack growth in TRIP steel under positive R-ratios , 2008 .

[22]  P. Zhu,et al.  Fatigue properties of transformation-induced plasticity and dual-phase steels for auto-body lightweight: Experiment, modeling and application , 2010 .

[23]  W. Bleck,et al.  On the effect of austenite stability on high cycle fatigue of TRIP 700 steel , 2013 .

[24]  N. Fredj,et al.  Fatigue life improvements of the AISI 304 stainless steel ground surfaces by wire brushing , 2004 .

[25]  E. Emadoddin,et al.  Effect of retained austenite characteristics on fatigue behavior and tensile properties of transformation induced plasticity steel , 2011 .

[26]  Rajiv S. Mishra,et al.  Probabilistic fatigue life prediction model for alloys with defects: Applied to A206 , 2011 .

[27]  M. Azrin,et al.  Fatigue strength of TRIP steels , 1980 .

[28]  M. Mitchell,et al.  Development of a Reversible Bending Fatigue Test Bed to Evaluate Bulk Properties Using Sub-Size Specimens , 2008 .

[29]  T. Niendorf,et al.  Unexpected cyclic stress-strain response of dual-phase high-entropy alloys induced by partial reversibility of deformation , 2018 .