Interaction of high-temperature deformation mechanisms in a Magnesium Alloy with Mixed Fine and Coarse Grains

Zelin, M. G.; Yang, Hongbo; Valiev, Ruslan Z.; Mukherjee, Amiya K.

doi:10.1007/bf02646132

Cited by 34 publications

(10 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Tan and Tan [14] and Zelin et al [37] have suggested the coexistence of GBS and slip in Mg alloys with a heterogeneous microstructure formed by large grains embedded in a matrix of small grains.…”

Section: A Low Stress Exponent Regime (N ͻ 3)mentioning

confidence: 98%

See 1 more Smart Citation

Deformation mechanisms responsible for the high ductility in a Mg AZ31 alloy analyzed by electron backscattered diffraction

Valle

Pérez‐Prado

Ruano

2005

Metall Mater Trans A

146

View full text Add to dashboard Cite

The microstructural evolution during tensile deformation of an AZ31 alloy with grain size ranging from 17 to 40 m, at intermediate temperatures, has been studied using electron backscattered diffraction (EBSD) and optical microscopy (OM) as the main characterization tools. Two deformation regimes could be distinguished. In the high-strain-rate regime, the stress exponent was found to be about 6, and the activation energy is close to that for Mg self-diffusion. These values are indicative of climbcontrolled creep. In the lower strain rate range, elongations higher than 300 pct were measured. In this range, significant dynamic grain growth takes place during the test, and thus, the predominant deformation mechanisms have been investigated by means of strain-rate-change tests. It was found that the stress exponent varied during the test between 1.7 and 2.5, while the activation energy remains close to that for grain-boundary diffusion. The EBSD analysis revealed, additionally, the appearance of low to moderately misoriented boundaries that tend to lay perpendicular to the tensile axis. The enhanced ductility of this AZ31 alloy in this regime is attributed to the operation of a sequence of deformation mechanisms. Initially, grain-boundary sliding governs deformation; once dynamic grain growth occurs, dislocation slip becomes gradually more important. Dislocation interaction gives rise to the appearance of new interfaces by continuous dynamic recrystallization (CDRX).

show abstract

Section: A Low Stress Exponent Regime (N ͻ 3)mentioning

confidence: 98%

“…The simultaneous operation of GBS and dislocation slip as independent deformation mechanisms has been previously observed in several materials such as, for example, Al, Mg, and Zn alloys, and INCONEL* 718. [14,[34][35][36][37][38][39] *INCONEL is a trademark of INCO Alloys International, Huntington Woods, WV.…”

Section: A Low Stress Exponent Regime (N ͻ 3)mentioning

confidence: 99%

Deformation mechanisms responsible for the high ductility in a Mg AZ31 alloy analyzed by electron backscattered diffraction

Valle

Pérez‐Prado

Ruano

2005

Metall Mater Trans A

146

View full text Add to dashboard Cite

show abstract

“…14) Many commercially available Mg alloys can be reduced in grain size to less than 10 mm. However, whether or not GBS can occur in finegrained Mg alloys remains unknown.…”

Section: )mentioning

confidence: 99%

Grain-Boundary Sliding in AZ31 Magnesium Alloys at Room Temperature to 523 K

et al. 2003

View full text Add to dashboard Cite

Rolled sheets of AZ31 Mg alloys were subjected to tensile testing at temperatures ranging from room temperature to 523 K. The occurrence of grain-boundary sliding (GBS) at room temperature was demonstrated by the displacement of scribed lines across grain boundaries of deformed samples. Surface relief of deformed samples was measured by use of a scanning laser microscope. GBS strain was calculated from the measured surface step height, and its temperature dependence was analyzed by a Dorn-type constitutive equation. GBS above 423 K was found to be pure GBS that was activated by resolved applied shear stress acting on grain boundaries. The activation energy for GBS was found to be 80 kJ/mol, which is in agreement with the activation energy for grain boundary diffusion. Meanwhile, GBS below 373 K was found to be slipinduced GBS, and its extent was found to be significantly greater than that expected from extrapolation of high-temperature values. The slipinduced GBS is considered to occur by plastic compatibility conditions in the presence of plastic strain anisotropy and by absorption and dissociation of lattice dislocations at grain boundaries.

show abstract

“…In particular, at this point it is key to develop simulation models that, supported by the experimental data available, can predict of the response of Mg alloys under different service conditions. The deformation mechanisms of Mg and Mg alloys that are operative at low strain rates have been extensively investigated over the past years (Couling et al, 1959;Kocks and Westlake, 1967;Kelley and Hosford, 1968a;Couret and Caillard, 1985;Chin and Mammel, 1970;Yoo, 1981;Vagaralia and Langdon, 1981;Zelin et al, 1992;Munroe and Tan, 1997;Agnew et al, 2001;Watanabe et al, 2001;Barnett, 2001;Agnew et al, 2003;Galiyev et al, 2003;Koike et al, 2003;Barnett, 2003;Gehrmann et al, 2005;Barnett et al, 2004a;Agnew and Duygulu, 2005;del Valle et al, 2005;Keshavarz and Barnett, 2006;Meza-García et al, 2007;Barnett, 2007;del Valle and Ruano, 2007;Al-Samman and Gottstein, 2008;Chino et al, 2008;Jain et al, 2008;Hutchinson et al, 2009;Ball and Prangnell, 1994;Lou et al, 2007). Slip in hexagonal close packed (HCP) metals may take place along the h11 20i (hai) direction on basal and non-basal (f10 10g-prismatic, f10 11g-pyramidal) planes.…”

Section: Introductionmentioning

confidence: 99%

Continuum modeling of the response of a Mg alloy AZ31 rolled sheet during uniaxial deformation

Fernández

Prado

Wei

et al. 2011

International Journal of Plasticity

103

View full text Add to dashboard Cite

a b s t r a c tLightweight magnesium alloys, such as AZ31, constitute alternative materials of interest for many industrial sectors such as the transport industry. For instance, reducing vehicle weight and thus fuel consumption can actively benefit the global efforts of the current environmental industry policies. To this end, several research groups are focusing their experimental efforts on the development of advanced Mg alloys. However, comparatively little computational work has been oriented towards the simulation of the micromechanisms underlying the deformation of these metals. Among them, the model developed by Staroselsky and Anand [Staroselsky, A., Anand, L., 2003. A constitutive model for HCP materials deforming by slip and twinning: application to magnesium alloy AZ31B. International Journal of Plasticity 19 (10), 1843-1864] successfully captured some of the intrinsic features of deformation in Magnesium alloys. Nevertheless, some deformation micromechanisms, such as cross-hardening between slip and twin systems, have been either simplified or disregarded. In this work, we propose the development of a crystal plasticity continuum model aimed at fully describing the intrinsic deformation mechanisms between slip and twin systems. In order to calibrate and validate the proposed model, an experimental campaign consisting of a set of quasi-static compression tests at room temperature along the rolling and normal directions of a polycrystalline AZ31 rolled sheet, as well as an analysis of the crystallographic texture at different stages of deformation, has been carried out. The model is then exploited by investigating stress and strain fields, texture evolution, and slip and twin activities during deformation. The flexibility of the overall model is ultimately demonstrated by casting light on an experimental controversy on the role of the pyramidal slip hc + ai versus compression twinning in the late stage of polycrystalline deformation, and a failure criterion related to basal slip activity is proposed.

show abstract

Interaction of high-temperature deformation mechanisms in a Magnesium Alloy with Mixed Fine and Coarse Grains

Cited by 34 publications

References 9 publications

Deformation mechanisms responsible for the high ductility in a Mg AZ31 alloy analyzed by electron backscattered diffraction

Deformation mechanisms responsible for the high ductility in a Mg AZ31 alloy analyzed by electron backscattered diffraction

Grain-Boundary Sliding in AZ31 Magnesium Alloys at Room Temperature to 523 K

Continuum modeling of the response of a Mg alloy AZ31 rolled sheet during uniaxial deformation

Contact Info

Product

Resources

About