In this paper, we show that there is a strong correlation between the strength differential (SD) effects in the plastic flow of the matrix, which arise from its dependence on the third stress invariant, void evolution, and ultimately the ductility of porous metallic polycrystals. For this purpose, detailed micromechanical finite-element analyses of three-dimensional unit cells are carried out. The plastic flow of the matrix is described by a criterion that accounts for strength-differential effects induced by shear deformation mechanisms of the constituent grains through a macroscopic parameter, k; only if there is no SD, k is zero, and the von Mises criterion is recovered. Numerical analyses are conducted for macroscopic proportional tensile loadings corresponding to fixed values of the stress triaxiality (ratio of the mean stress to the second stress invariant). It is shown that for the same macroscopic loading, the local plastic strains and the local stress distribution are strongly dependent on the sign of the parameter k. This in turn has a huge impact on damage accumulation, and ultimately affects the ductility of the porous polycrystals. Specifically, for axisymmetric loadings at third stress invariant positive, the rate of void growth is the slowest in the material with k negative, while the reverse holds true for equibiaxial tension (third stress invariant negative). Consequently, the ductility in axisymmetric tension at third-stress invariant positive is also markedly different from that in equibiaxial tension (third-stress invariant negative).
Accepted:
Published online:
José Luis Alves 1, 2; Oana Cazacu 2
@article{CRMECA_2015__343_2_107_0, author = {Jos\'e Luis Alves and Oana Cazacu}, title = {Correlation between strength differential effects in the plastic flow of the matrix and the rate of damage growth in porous polycrystals}, journal = {Comptes Rendus. M\'ecanique}, pages = {107--120}, publisher = {Elsevier}, volume = {343}, number = {2}, year = {2015}, doi = {10.1016/j.crme.2014.12.002}, language = {en}, }
TY - JOUR AU - José Luis Alves AU - Oana Cazacu TI - Correlation between strength differential effects in the plastic flow of the matrix and the rate of damage growth in porous polycrystals JO - Comptes Rendus. Mécanique PY - 2015 SP - 107 EP - 120 VL - 343 IS - 2 PB - Elsevier DO - 10.1016/j.crme.2014.12.002 LA - en ID - CRMECA_2015__343_2_107_0 ER -
%0 Journal Article %A José Luis Alves %A Oana Cazacu %T Correlation between strength differential effects in the plastic flow of the matrix and the rate of damage growth in porous polycrystals %J Comptes Rendus. Mécanique %D 2015 %P 107-120 %V 343 %N 2 %I Elsevier %R 10.1016/j.crme.2014.12.002 %G en %F CRMECA_2015__343_2_107_0
José Luis Alves; Oana Cazacu. Correlation between strength differential effects in the plastic flow of the matrix and the rate of damage growth in porous polycrystals. Comptes Rendus. Mécanique, Mechanics of granular and polycrystalline solids, Volume 343 (2015) no. 2, pp. 107-120. doi : 10.1016/j.crme.2014.12.002. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/j.crme.2014.12.002/
[1] Void growth in an elastic–plastic medium, J. Appl. Mech., Volume 39 (1972), pp. 964-969
[2] Influence of voids on shear band instabilities under plane strain conditions, Int. J. Fract., Volume 17 (1981), pp. 389-407
[3] Void growth and coalescence in porous plastic solids, Int. J. Solids Struct., Volume 24 (1988) no. 8, pp. 835-853
[4] Dilatant plasticity or upper bound estimates for porous ductile solids, Acta Metall. Mater., Volume 42 (1994), pp. 2561-2577
[5] Numerical analysis of the influence of the Lode parameter on void growth, Int. J. Solids Struct., Volume 38 (2001), pp. 5847-5856
[6] Porosity evolution in a creeping single crystal, Model. Simul. Mater. Sci. Eng., Volume 20 (2012), pp. 1-23
[7] Relation of experiments to mathematical theories of plasticity, J. Appl. Mech., Volume 16 (1949), pp. 349-357
[8] Theory of Perfectly Plastic Solids, John Wiley & Sons, Inc., 1951
[9] The relationship of hardness measurements to the tensile and compression flow curves, General Electric Research Laboratory, 1955 (WADC technical report 55-114)
[10] Non-linear mechanical response of various metals: I dynamic and static response to simple compression, tension and torsion in the as received and annealed states, J. Phys. D, Volume 10 (1977), pp. 519-531
[11] Twining and directional slip as a cause for strength differential effect, Metall. Trans., Volume 4 (1973), pp. 1424-1425
[12] A criterion for description of anisotropy and yield differential effects in pressure-insensitive materials, Int. J. Plast., Volume 22 (2004), pp. 2027-2045
[13] Simulation of the rolling and shear texture of brass by the Taylor theory adapted for mechanical twinning, Acta Metall., Volume 26 (1978), pp. 591-604
[14] Calculated and experimental orientation distributions of twin lamellae in rolled brass, Acta Metall., Volume 37 (1989), pp. 1191-1198
[15] Modelling of texture evolution for materials of hexagonal symmetry—II. Application to zirconium and titanium α or near α alloys, Acta Metall. Mater., Volume 43 (1995), pp. 1619-1630
[16] Importance of twinning in static and dynamic compression of a Ti–6Al–4V titanium alloy with an equiaxed microstructure, Mater. Sci. Eng. A, Volume 537 (2012), pp. 1-10
[17] Mechanical response and texture evolution of AZ31 alloy at large strains for different strain rates and temperatures, Int. J. Plast., Volume 27 (2011), pp. 688-706
[18] Texture evolution and anisotropy in the thermo-mechanical response of UFG Ti processed via equal channel angular pressing, Int. J. Plast., Volume 30–31 (2012), pp. 202-217
[19] Orthotropic yield criterion for hexagonal closed packed materials, Int. J. Plast., Volume 22 (2006), pp. 1171-1194
[20] Effect of single-crystal plastic deformation mechanisms on the dilatational plastic response of porous polycrystals, Int. J. Solids Struct., Volume 49 (2012), pp. 3838-3852
[21] Three-dimensional numerical simulation of the deep-drawing process using solid finite element, J. Mater. Process. Technol., Volume 97 (2000), pp. 100-106
[22] Algorithms and strategies for treatment of large deformation frictional contact in the numerical simulation of deep drawing process, Arch. Comput. Methods Eng., Volume 15 (2008), pp. 113-162
[23] Analysis of the cup-cone fracture in a round tensile bar, Acta Metall., Volume 32 (1984), pp. 157-169
[24] Modelling the mechanical response of polycrystals deforming by climb and glide, Philos. Mag., Volume 90 (2010), pp. 567-583
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