The quaternary Q phase is an important precipitate phase in the Al-Cu-Mg-Si alloy system and its accurate thermodynamic description is crucial for further tailoring this material class for light-weight structural applications. In order to achieve an improved thermochemical parameter set of this phase, we used a combination of experimental measurements and first-principles calculations, which was focussed on the heat capacity. Its accurate experimental determination required the preparation of pure samples of Q phase and sophisticated calorimetric measurements. On the theoretical side, a simultaneous treatment of lattice vibrations within the quasiharmonic approximation, electronic excitations, and configuration entropy within the compound energy formalism were required to achieve a complete description of the heat capacity. The evaluation demonstrates the high predictive power of the first-principles as well as the Calphad modeling.
This is a preview of subscription content, access via your institution.
Buy single article
Instant access to the full article PDF.
Tax calculation will be finalised during checkout.
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
Tax calculation will be finalised during checkout.
D.J. Chakrabarti and D.E. Laughlin, Phase Relations and Precipitation in Al-Mg-Si Alloys with Cu Additions, Prog. Mater Sci., 2004, 49, p 389-410
S. Esmaeili, X. Wang, D.J. Lloyd, and W.J. Poole, On the Precipitation-Hardening Behavior of the Al-Mg-Si-Cu Alloy AA6111, Metall. Mater. Trans. A, 2003, 34(13), p 751-763
A. Biswas, D.J. Siegel, and D.N. Seidman, Compositional Evolution of Q-Phase Precipitates in an Aluminum Alloy, Acta Mater., 2014, 75, p 322-336
C.-A. Gandin, Modeling of Solidification, Grain Structures and Segregation in Metallic Alloys, Comptes Rendus Phys., 2010, 11, p 216-225
L. Thuinet and H. Combeau, A New Model of Microsegregation for Macrosegregation Computation in Multicomponent Steels, Comput. Mater. Sci., 2009, 45, p 294-304, ibd. pp 285-293
T. Kraft, M. Rettenmayr, and H.E. Exner, An Extended Numerical Procedure for Predicting Microstructure and Microsegregation in Multicomponent Alloys, Model. Simul. Mater. Sci. Eng., 1996, 4, p 161-177
M. Rappaz and M. Rettenmayr, Simulation of Solidification, Curr. Opin. Solid State Mater. Sci., 1998, 3, p 275-282
A. Löffler, J. Gröbner, M. Hampl, H. Engelhardt, R. Schmid-Fetzer, and M. Rettenmayr, Solidifying Incongruently Melting Intermetallic Phases as Bulk Single Phases Using the Example of Al2Cu and Q-Phase in the Al-Mg-Cu-Si System, J. Alloys Compd., 2012, 515, p 123-127
C. Wolverton, Crystal Structure and Stability of Complex Precipitate Phases in Al-Cu-Mg-(Si) and Al-Mg-Zn Alloys, Acta Mater., 2001, 49, p 3129-3142
H.N. Thi, B. Drevet, J.M. Debierre, D. Camel, Y. Dabo, and B. Billia, Preparation of the Initial Solid-Liquid Interface and Melt in Directional Solidification, J. Cryst. Growth, 2003, 253, p 539-548
A. Löffler, K. Reuther, H. Engelhardt, D.M. Liu, and M. Rettenmayr, Resolidification of the Mushy Zone of Multiphase and Multicomponent Alloys in a Temperature Gradient—Experiments and Modeling, Acta Mater., 2015, 91, p p34-p40
M. Buchmann and M. Rettenmayr, Microstructure Evolution During Melting and Resolidification in a Temperature Gradient, J. Cryst. Growth, 2005, 284, p 544-553
D. Liu, Y. Su, X. Li, L. Luo, J. Guo, and H. Fu, Influence of Thermal Stabilization on the Solute Concentration of the Melt in Directional Solidification, J. Cryst. Growth, 2010, 312, p 3658-3664
G. Kresse and J. Hafner, Ab Initio Molecular Dynamics for Liquid Metals, Phys. Rev. B, 1993, 47, p 558-561
G. Kresse and J. Furthmüller, Efficiency of Ab-Initio Total Energy Calculations for Metals and Semiconductors Using a Plane-Wave Basis Set, Comput. Mater. Sci., 1996, 6, p 15-50
G. Kresse and J. Furthmüller, Efficient Iterative Schemes for Ab Initio Total-Energy Calculations Using a Plane-Wave Basis Set, Phys. Rev. B, 1996, 54, p 11169-11186
J.P. Perdew, K. Burke, and M. Ernzerhof, Generalized Gradient Approximation Made Simple, Phys. Rev. Lett., 1996, 77, p 3865-3868
P.E. Blöchl, Projector Augmented-Wave Method, Phys. Rev. B, 1994, 50, p 17953-17979
H.J. Monkhorst and J.D. Pack, Special Points for Brillouin-Zone Integrations, Phys. Rev. B, 1976, 13, p 5188-5192
L. Arnberg, B. Aurivillius, E. Wahlström, G. Malmros, J. Sjöblom, T.G. Strand, and V.F. Sukhoverkhov, The Crystal Structure of Al(x)Cu2 Mg(12-x)Si7 (h-AlCuMgSi), Acta Chem. Scand., 1980, 34a, p 1-5
B. Grabowski, T. Hickel, and J. Neugebauer, Ab Initio Study of the Thermodynamic Properties of Nonmagnetic Elementary fcc Metals: Exchange-Correlation-Related Error Bars and Chemical Trends, Phys. Rev. B, 2007, 76, p 024309
N.D. Mermin, Thermal Properties of the Inhomogeneous Electron Gas, Phys. Rev., 1965, 137, p A1441
B. Sundman, B. Jansson, and J.-O. Andersson, The Thermocalc Database System, CALPHAD, 1985, 9, p 153-190
T. Hickel, B. Grabowski, F. Körmann, and J. Neugebauer, Advancing Density Functional Theory to Finite Temperatures: Methods and Applications in Steel Design, J. Phys.: Condens. Matter, 2012, 24, p 053202
A. Glensk, B. Grabowski, T. Hickel, and J. Neugebauer, Understanding Anharmonicity in fcc Materials: From its Origin to Ab Initio Strategies Beyond the Quasiharmonic Approximation, Phys. Rev. Lett., 2015, 114, p 195901
A. Glensk, B. Grabowski, T. Hickel, J. Neugebauer, in preparation.
A. Zendegani, F. Körmann, T. Hickel, B. Hallstedt, J. Neugebauer, in preparation.
M. Schick, B. Hallstedt, A. Glensk, B. Grabowski, T. Hickel, J. Gröbner, M. Hampl, J. Neugebauer, and R. Schmid-Fetzer, Assessment of the Binary Mg-Si Phase Diagram, CALPHAD, 2012, 37, p 77-86
C. Ravi and C. Wolverton, First-Principles Study of Crystal Structure and Stability of Al-Mg-Si-(Cu) Precipitates, Acta Mater., 2004, 52, p 4213-4227
C. Ravi, C. Wolverton, Comparison of thermodynamic databases for 3xx and 6xxx aluminum alloys. Metall. Mater. Trans.A 2005, 36(8), p 2013-2023
K. Chang, S. Liu, D. Zhao, Y. Du, L. Zhou, and L. Chen, Thermodynamic Description of the Al-Cu-Mg-Mn-Si Quinary System and Its Application to Solidification Simulation, Thermochim. Acta, 2011, 512, p 258-267
The funding of this work by the Deutsche Forschungsgemeinschaft (DFG) within the joint Project PAK 461 under Grant Nos. Re1261/7, Ne428/12, and Schm 588/35 is gratefully acknowledged.
About this article
Cite this article
Löffler, A., Zendegani, A., Gröbner, J. et al. Quaternary Al-Cu-Mg-Si Q Phase: Sample Preparation, Heat Capacity Measurement and First-Principles Calculations. J. Phase Equilib. Diffus. 37, 119–126 (2016). https://doi.org/10.1007/s11669-015-0426-y
- ab initio methods
- CALPHAD approach
- heat capacity
- thermodynamic assessment