Abstract
In this study, precipitation of Ca in Al-Mg alloys containing a trace of Ca during homogenization was investigated using a transmission electron microscope (TEM) and calculated phase diagrams. TEM result indicated that the Ca-based particles found in the examined sample are Ca7Mg7.5Si14. From the calculation of Scheil-Gulliver cooling, it was found that the Ca was formed as Al4Ca and C36 laves phases with Mg2Si and Al13Fe4 from other impurities phase during solidification. No Ca-Mg-Si ternary phase existed at the homogenization temperature in the calculated phase diagram. From the phase diagram of Al-Al4Ca-Mg2Si three-phase isothermal at 490℃, it was shown that Ca7Mg6Si14 phase co-exists with Al, Mg2Si and Al4Ca in the largest region and with only Al and Mg2Si in Al4Ca-poor regions. It was thought that the Ca7Mg6Si14 ternary phase was formed by the interaction between Mg2Si and Al4Ca considering that the segregation can occur throughout the entire microstructures.
Go to article
Bibliography
[1] J.R. Davis, ASM International, Aluminum and Aluminum Alloys, Materials Park 1993.
[2] G . Wu, K. Dash, M.L. Galano, K.A.Q. O’Reilly, Corros. Sci. 155, 97 (2019).
[3] B.H. Kim, S.H. Ha, Y.O. Yoon, H.K. Lim, S.K. Kim, D.H. Kim, Mater. Lett. 228, 108 (2018).
[4] S.H. Ha, B.H. Kim, Y.O. Yoon, H.K. Lim, T.W. Lee, S.H. Lim, S.K. Kim, Sci. Adv. Mater. 10, 697 (2018).
[5] D. Ajmera, E. Panda, Corros. Sci. 102, 425 (2016).
[6] S.H. Ha, J.K. Lee, S.K. Kim, Mater. Trans. 49, 1081 (2008).
[7] S.H. Ha, B.H. Kim, Y.O. Yoon, H.K. Lim, T.W. Lee, S.H. Lim, S.K. Kim, Int. J. Metalcast. 13, 121 (2019).
[8] J.W. Jeong, J.S. Im, K. Song, M.H. Kwon, S.K. Kim, Y.B. Kang, S.H. Oh, Acta Mater. 61, 3267 (2013).
[9] K. Ozturk, L.Q. Chen, Z.K. Liu, J. Alloys Compd. 340, 199 (2002).
[10] C.W. Bale, E. Bélisle, P. Chartrand, S.A. Decterov, G. Eriksson, A.E. Gheribi, K. Hack, I.H. Jung, Y.B. Kang, J. Melançon, A.D. Pelton, S. Petersen, C. Robelin, J. Sangster, P. Spencer, M.A. Van Ende, Calphad 54, 35 (2016).
Go to article