A microstructure-based model for describing strain softening during compression of Al-30%wt Zn alloy

A microstructural-based model, describing the plastic behavior of Al-30wt% Zn alloy, is proposed and the effect of solid solution decomposition, Orowan looping, twinning and grain refinement is analyzed. It is assumed that the plastic deformation process is dominated by strain-induced solute diffusion and dislocation motion. To capture the essential physics, a law describing the evolution of the mean free path of dislocations with plastic strain is proposed which reproduces the experimentally observed strain softening.

[1]  R. Valiev,et al.  Gradual softening of Al-Zn alloys during high-pressure torsion , 2012 .

[2]  C. Cepeda-Jiménez,et al.  Mechanical properties at room temperature of an Al–Zn–Mg–Cu alloy processed by equal channel angular pressing , 2011 .

[3]  I. Samajdar,et al.  Development of grain structure during superplastic deformation of an Al–Zn–Mg–Cu–Zr alloy containing Sc , 2011 .

[4]  B. Muddle,et al.  Some observations on deformation-related discontinuous precipitation in an Al-14.6at.%Zn alloy , 2011 .

[5]  P. Bai,et al.  Microstructure and mechanical properties of a large billet of spray formed Al–Zn–Mg–Cu alloy with high Zn content , 2009 .

[6]  O. Ruano,et al.  An evidence of high strain rate superplasticity at intermediate homologous temperatures in an Al-Zn-Mg-Cu alloy processed by high-pressure torsion , 2009 .

[7]  G. Purcek,et al.  Microstructural evolution and mechanical properties of Al–40 wt.%Zn alloy processed by equal-channel angular extrusion , 2009 .

[8]  Alexis Deschamps,et al.  Influence of cooling rate on the precipitation microstructure in a medium strength Al–Zn–Mg alloy , 2009 .

[9]  R. Valiev,et al.  Thermal evolution and grain boundary phase transformations in severely deformed nanograined Al-Zn alloys , 2008 .

[10]  T. Langdon,et al.  The effect of severe plastic deformation on precipitation in supersaturated Al-Zn-Mg alloys , 2007 .

[11]  R. Valiev,et al.  Softening of nanostructured Al–Zn and Al–Mg alloys after severe plastic deformation , 2006 .

[12]  R. C. Picu,et al.  Effect of solute distribution on the strain rate sensitivity of solid solutions , 2006 .

[13]  Frédéric Barlat,et al.  Strain rate sensitivity of the commercial aluminum alloy AA5182-O , 2005 .

[14]  F. Barlat,et al.  Artificial aging and shear deformation behaviour of 6022 aluminium alloy , 2004 .

[15]  F. Barlatb,et al.  Strain rate sensitivity of the commercial aluminum alloy AA 5182 - , 2004 .

[16]  Frédéric Barlat,et al.  Plastic flow for non-monotonic loading conditions of an aluminum alloy sheet sample , 2003 .

[17]  F. Barlat,et al.  Effect of texture and microstructure on strain hardening anisotropy for aluminum deformed in uniaxial tension and simple shear , 2003 .

[18]  U. F. Kocks,et al.  Physics and phenomenology of strain hardening: the FCC case , 2003 .

[19]  J. Narayan,et al.  Mechanisms for grain size hardening and softening in Zn , 2002 .

[20]  Frédéric Barlat,et al.  Hardening behavior and structural evolution upon strain reversal of aluminum alloys , 2002 .

[21]  M. Cieslar,et al.  The influence of processing route on the plastic deformation of Al–Zn–Mg–Cu alloys , 2002 .

[22]  F. Froes,et al.  Microstructure and properties of a new super-high-strength Al–Zn–Mg–Cu alloy C912 , 1997 .

[23]  V. Stolyarov,et al.  Influence of severe plastic deformation on aging effect of Al-Zn-Mg-Cu-Zr alloy , 1997 .

[24]  A. Deschamps,et al.  Anomalous strain hardening behaviour of a supersaturated Al-Zn-Mg alloy , 1997 .

[25]  R. Valiev,et al.  Fabrication of submicrometer-grained Zn–22% Al by torsion straining , 1996 .

[26]  N. Hansen.  Microstructure and flow stress of cell forming metals , 1992 .

[27]  J. Gracio,et al.  Effect of grain size on substructural evolution and plastic behaviour of copper , 1989 .

[28]  P. McCormick,et al.  Plastic flow instability in a precipitation hardened AlZnMg alloy , 1987 .