Multiscale ductile fracture integrating tomographic characterization and 3-D simulation

Abstract Ductile fracture in alloys is a multiscale process in which primary voids formed at micron-scale particles coalesce by a zig-zag pattern of shear localization driven by finer-scale microvoiding at submicron-scale secondary particles. Employing the method of serial sectioning, unprecedented 3-D microstructural reconstructions of steel crack-tip process zones are obtained and implemented into a large-scale simulation for ductile fracture analysis. A quantitative understanding of the microvoid sheeting mechanism and mixed-mode failure controlling the zig-zag fracture surface are presented using the modeling technique utilized herein. We define and quantify metrics of fracture by analyzing the crack opening distance, process zone size, zig-zag wavelength and void growth ratios in the crack tip reconstructions. The quantitative agreement of these metrics between experiment and simulation supports a new and developing predictive structure/property theory to enable materials design.

[1]  Brian Moran,et al.  The 3-D computational modeling of shear-dominated ductile failure in steel , 2006 .

[2]  Cahal McVeigh,et al.  Multiresolution modeling of ductile reinforced brittle composites , 2009 .

[3]  D. M. Tracey,et al.  On the ductile enlargement of voids in triaxial stress fields , 1969 .

[4]  C. Shih,et al.  Relationships between the J-integral and the crack opening displacement for stationary and extending cracks , 1981 .

[5]  Morris Azrin,et al.  Microvoid formation during shear deformation of ultrahigh strength steels , 1989 .

[6]  Huajian Gao,et al.  Mechanism-based strain gradient plasticity— I. Theory , 1999 .

[7]  Norman A. Fleck,et al.  A phenomenological theory for strain gradient effects in plasticity , 1993 .

[8]  P. Thomason,et al.  Ductile Fracture of Metals , 1990 .

[9]  Wing Kam Liu,et al.  A renormalization approach to model interaction in microstructured solids: Application to porous elastomer , 2012 .

[10]  G. B. Olson,et al.  Designing a New Material World , 2000, Science.

[11]  Shan Tang,et al.  Three-dimensional ductile fracture analysis with a hybrid multiresolution approach and microtomography , 2013 .

[12]  F. Delannay,et al.  A method for the metallographical measurement of the CTOD at cracking initiation and the role of reverse plasticity on unloading , 2000 .

[13]  N. Aravas On the numerical integration of a class of pressure-dependent plasticity models , 1987 .

[14]  Wing Kam Liu,et al.  Multiresolution continuum modeling of micro-void assisted dynamic adiabatic shear band propagation , 2010 .

[15]  J. Hutchinson,et al.  Modification of the Gurson Model for shear failure , 2008 .

[16]  Franck J. Vernerey,et al.  A micromorphic model for the multiple scale failure of heterogeneous materials , 2008 .

[17]  Franck J. Vernerey,et al.  Multi-scale micromorphic theory for hierarchical materials , 2007 .

[18]  J. W. Bray,et al.  Fracture toughness and the extents of primary void growth , 1992 .

[19]  Rong Tian,et al.  A multiresolution continuum simulation of the ductile fracture process , 2010 .

[20]  Franck J. Vernerey,et al.  An interactive micro-void shear localization mechanism in high strength steels , 2007 .

[21]  H. Saunders,et al.  Advanced Fracture Mechanics , 1985 .

[22]  K. Ravi-Chandar,et al.  The Sandia Fracture Challenge: blind round robin predictions of ductile tearing , 2014, International Journal of Fracture.

[23]  Andrzej L. Wojcieszynski,et al.  A discussion of the effect of inclusion volume fraction on the toughness of steel , 2007 .

[24]  Cahal McVeigh,et al.  Linking microstructure and properties through a predictive multiresolution continuum , 2008 .