Abstract
Investigation of creep behavior of AZ31 magnesium alloy at three different temperatures (230, 270, and 350 °C) and stresses of 1–13 MPa reveals that grain boundary sliding (GBS) is the dominant creep mechanism at elevated temperatures and low stresses. GBS and Mg17Al12 precipitates in Mg–Al alloys result in stress concentration sites for cavity formation during high-temperature low-strain rate deformation leading to premature failures. Analysis of fractured surfaces of samples deformed at 350 °C reveals that brittle-type fracture (inter-granular and trans-granular) is the dominant mechanism at low stresses (σ = 1–5 MPa) while at higher stresses (σ = 7–13 MPa) dimple ruptures are predominant. Grain growth, dynamic recovery, and a decrease in dislocation density are characteristics of low-stress deformation of AZ31 alloys in GBS region whereas increase in dislocation density and dynamic recrystallization is noted during deformation under higher stresses where dislocation creep was noted to be predominant.
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N. Farahbakhsh, P.S. Roodposhti, A.S. Ayoub, R.A. Venditti, J.S. Jur, Melt extrusion of polyethylene nanocomposites reinforced with nanofibrillated cellulose from cotton and wood sources. J. Appl. Polym. Sci. (2015). doi:10.1002/app.41857
P.S. Roodposhti, A. Sarkar, K.L. Murty, A review of the influence of production methods and intermetallic phases on the creep properties of AZ91. Magn. Technol. 2014, 59–64 (2014)
H. Somekawa, H. Watanabe, T. Mukai, Effect of solute atoms on grain boundary sliding in magnesium alloys. Philos. Mag. 94(12), 1345–1360 (2014)
S.W. Chung, H. Watanabe, W.-J. Kim, K. Higashi, Creep deformation mechanisms in coarse-grained solid solution Mg alloys. Mater. Trans. 45(4), 1266–1271 (2004)
R. Korla, A.H. Chokshi, A constitutive equation for grain boundary sliding: an experimental approach. Metall. Mater. Trans. A 45(2), 698–708 (2013)
R.B. Figueiredo, T.G. Langdon, Developing superplasticity in a magnesium AZ31 alloy by ECAP. J. Mater. Sci. 43(23–24), 7366–7371 (2008)
S. Spigarelli, M. El Mehtedi, D. Ciccarelli, M. Regev, Effect of grain size on high temperature deformation of AZ31 alloy. Mater. Sci. Eng. A 528(22–23), 6919–6926 (2011)
S. Spigarelli, M. El Mehtedi, M. Cabibbo, E. Evangelista, J. Kaneko, A. Jäger, V. Gartnerova, Analysis of high-temperature deformation and microstructure of an AZ31 magnesium alloy. Mater. Sci. Eng. A 462(1–2), 197–201 (2007)
H. Somekawa, K. Hirai, H. Watanabe, Y. Takigawa, K. Higashi, Dislocation creep behavior in Mg–Al–Zn alloys. Mater. Sci. Eng. A 407(1–2), 53–61 (2005)
K. Ishikawa, H. Watanabe, T. Mukai, High temperature compressive properties over a wide range of strain rates in an AZ31 magnesium alloy. J. Mater. Sci. 40(7), 1577–1582 (2005)
A.G. Beer, M.R. Barnett, Influence of initial microstructure on the hot working flow stress of Mg–3Al–1Zn. Mater. Sci. Eng. A 423(1–2), 292–299 (2006)
S.-H. Choi, J.K. Kim, B.J. Kim, Y.B. Park, The effect of grain size distribution on the shape of flow stress curves of Mg–3Al–1Zn under uniaxial compression. Mater. Sci. Eng. A 488(1–2), 458–467 (2008)
H.-K. Kim, W.-J. Kim, Creep behavior of AZ31 magnesium alloy in low temperature range between 423 and 473 K. J. Mater. Sci. 42(15), 6171–6176 (2007)
J.A. Del Valle, O.A. Ruano, Deformation mechanisms responsible for the high ductility in a Mg AZ31 alloy analyzed by electron backscattered diffraction. Metall. Mater. Trans. A 36, 1427–1438 (2005)
S.W. Chung, C.S. Chung, D. Kum, Super plasticity in thin magnesium alloy sheets and deformation mechanism maps for magnesium. Acta Mater. 49, 3337–3345 (2001)
K. Kitazono, E. Sato, K. Kuribayashi, Internal stress superplasticity in polycrystalline AZ31 magnesium alloy. Scripta Mater. 44(12), 2695–2702 (2001)
P. Shahbeigi Roodposhti, N. Farahbakhsh, A. Sarkar, K.L. Murty, A review on the equal channel angular process of commercially pure titanium, in Proc. MS&T14 (2014), pp. 1559–1566
J. Koike, R. Ohyama, T. Kobayashi, M. Suzuki, K. Maruyama, Grain-boundary sliding in AZ31 magnesium alloys at room temperature to 523 K. Mater. Trans. 44(4), 445–451 (2003)
S.S. Vagarali, T.G. Langdon, Deformation mechanisms in HCP metals at elevated temperatures—II. Creep behavior of a Mg-0.8% Al solid solution alloy. Acta Metall. 30(6), 1157–1170 (1982)
S. Ansary, R. Mahmudi, M.J. Esfandyarpour, Creep of AZ31 Mg alloy: a comparison of impression and tensile behavior. Mater. Sci. Eng. A 556, 9–14 (2012)
H. Somekawa, T. Mukai, Molecular dynamics simulation of grain boundary plasticity in magnesium and solid-solution magnesium alloys. Comput. Mater. Sci. 77, 424–429 (2013)
R.B. Figueiredo, T.G. Langdon, Principles of grain refinement and superplastic flow in magnesium alloys processed by ECAP. Mater. Sci. Eng. A 501(1–2), 105–114 (2009)
M.R.R. Panicker, A.H. Chokshi, Influence of grain size on high temperature fracture in a Mg AZ31 alloy. Mater. Sci. Eng. A 528(7–8), 3031–3036 (2011)
C.J. Lee, J.C. Huang, Cavitation characteristics in AZ31 Mg alloys during LTSP or HSRSP. Acta Mater. 52(10), 3111–3122 (2004)
Y.C. Lin, M.-S. Chen, J. Zhong, Effect of temperature and strain rate on the compressive deformation behavior of 42CrMo steel. J. Mater. Process. Technol. 205(1–3), 308–315 (2008)
J. Deng, Y.C. Lin, S. Li, J. Chen, Y. Ding, Hot tensile deformation and fracture behaviors of AZ31 magnesium alloy. Mater. Des. 49, 209–219 (2013)
G. Williamson, W. Hall, X-ray line broadening from filed aluminium and wolfram. Acta Metall. 1(1), 22–31 (1953)
P.S. Roodposhti, A. Sarkar, K.L. Murty, Microstructure development of high temperature deformed AZ31 magnesium alloys. Mater. Sci. Eng. A 626, 195–202 (2015)
P.S. Roodposhti, A. Sarkar, K.L. Murty, Creep deformation mechanisms and related microstructure development of AZ31 Magnesium alloy. Magn. Technol. (2015), in press
G.K. Williamson, R.E. Smallman III, Dislocation densities in some annealed and cold-worked metals from measurements on the X-ray debye-scherrer spectrum. Philos. Mag. 1(1), 34–46 (1956)
W.P. Peng, P.J. Li, P. Zeng, L.P. Lei, Hot deformation behavior and microstructure evolution of twin-roll-cast Mg–2.9Al–0.9Zn alloy: a study with processing map. Mater. Sci. Eng. A 494(1–2), 173–178 (2008)
O. Sabokpa, A. Zarei-Hanzaki, H.R. Abedi, An investigation into the hot ductility behavior of AZ81 magnesium alloy. Mater. Sci. Eng. A 550, 31–38 (2012)
W. Qudong, C. Wenzhou, Z. Xiaoqin, L.U. Yizhen, Effects of Ca addition on the microstructure and mechanical properties of AZ91 magnesium alloy. J. Mater. Sci. 6, 3035–3040 (2001)
J.N. Greenwood, D. Miller, J. Suiter, Intergranular cavitation in stressed metals. Acta Metall. 2(2), 250–258 (1954)
R. Raj, M. Ashby, Intergranular fracture at elevated temperature. Acta Metall. 23(6), 653–666 (1975)
B. Cunningham, K.H.G. Ashbee, Marmem engines. Acta Metall. 25(11), 1315–1321 (1977)
A.H. Chokshi, T.G. Langdon, A model for diffusional cavity growth in superplasticity. Acta Metall. 35(5), 1089–1101 (1987)
P.D. Nicolaou, S.L. Semiatin, Modeling of cavity coalescence during tensile deformation. Acta Mater. 47(13), 3679–3686 (1999)
P. Nicolaou, S. Semiatin, An analysis of the effect of continuous nucleation and coalescence on cavitation during hot tension testing. Acta Mater. 48(13), 3441–3450 (2000)
L. Angeles, The development of cavity growth maps for superplastic materials. J. Mater. Sci. 21, 2073–2082 (1986)
R. Raj, Nucleation of cavities at second phase particles in grain boundaries. Acta Metall. 26(6), 995–1006 (1978)
A.H. Chokshit, A.K. Mukherjee, An analysis of cavity nucleation in superplasticity. Acta Metall. 37(11), 3007–3017 (1989)
A.H. Chokshi, Cavity nucleation and growth in superplasticity. Mater. Sci. Eng. A 410–411, 95–99 (2005)
D.A. Miller, T.G. Langdon, An analysis of cavity growth during superplasticity. Metall. Trans. A 10A, 1869–1874 (1979)
A.H. Chokshi, A.K. Mukherjee, The cavitation and fracture characteristics of a superplastic Al-Cu-Li-Zr alloy. Mater. Sci. Eng. A 110, 49–60 (1989)
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This research is supported by the National Science Foundation Grant 0968825.
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Roodposhti, P.S., Sarkar, A. & Murty, K.L. Fracture Behavior of AZ31 Magnesium Alloy During Low-Stress High-Temperature Deformation. Metallogr. Microstruct. Anal. 4, 91–101 (2015). https://doi.org/10.1007/s13632-015-0189-1
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DOI: https://doi.org/10.1007/s13632-015-0189-1