Abstract
In titanium casting, a reaction byproduct known as alpha-case is a hard and brittle phase layer that exists on the surface of cast objects. This reaction layer may be detrimental to the mechanical properties of cast objects and may complicate the finishing processes. To investigate the formation of the alpha-case layer during the casting of commercially pure titanium (CP-Ti) and Ti-6Al-4V alloy, both metal ingots were cast in spinel-based investments in a controlled environment. The cast samples were metallographically prepared and analyzed for the thicknesses of alpha-case layer depth and the metal matrix. The samples were characterized using light microscopy, Vickers microhardness testing, X-ray diffractometry, and extended X-ray absorption fine structure spectrometry. The alpha-case layer on the CP-Ti cast sample was thicker than that of the Ti-6Al-4V cast sample due to the ability of the α-titanium matrix to uptake oxygen faster, which in turn is attributed to the higher diffusion coefficient of the α-titanium phase. A metastable Ti3O phase was observed as an intermediate reaction product which could be transformed into the alpha-case layer and the α-titanium phase.
Similar content being viewed by others
References
M. Peters, J. Kumpfert, C. H. Ward and C. Leyens: Titanium and Titanium Alloys, Wiley-VCH Verlag GmbH & Co. KGaA, 2005, pp 333–350.
D. Eylon, S. Fujishiro, Pamela J. Postans and F. H. Froes: JOM 1984, vol. 36, pp. 55-6
Łukaszewicz A, Smolarczyk P, Szota M, Nabiałek M, Bukowska A (2013) J Achiev Mater Manuf Eng 61:281-288
B. Kasemo: J. Prosthet. Dent. 1983, vol. 49, pp. 832-837.
J. Breme, E. Eisenbarth and V. Biehl: Titanium and Titanium Alloys, Wiley-VCH Verlag GmbH & Co. KGaA, 2005, pp 423–51.
H. J. Rack and J. I. Qazi: Mater. Sci. Eng. C, 2006, vol. 26, pp. 1269-1277.
M. Niinomi: J. Mech. Behav. Biomed. Mater., 2008, vol. 1, pp. 30-42.
S.S.d. Rocha, F. Nogueira, A.R.F. Pieralini, R.F.R. and G.L. Adabo: Braz Oral Res., 2010, vol. 24, pp. 147–52.
T. Papadopoulos, S. S. Zinelis and M. Vardavoulias: J. Mater. Sci., 1999, vol. 34, pp. 3639-3646.
R. C. Atwood, P. D. Lee and R. V. Curtis: Dent Mater., 2005, vol. 21, pp. 178-186.
R. I. Jaffee: Prog. Met. Phys., 1958, vol. 7, pp. 65-163.
J. Unnam, R. N. Shenoy and R. K. Clark: Oxid. Met., 1986, vol. 26, pp. 231-252.
R. Gaddam, B. Sefer, R. Pederson and M.-L. Antti: Mater. Charact., 2015, vol. 99, pp. 166-174.
H. Guleryuz and H. Cimenoglu: J. Alloys Compd., 2009, vol. 472, pp. 241-246.
K. S. Chan, M. Koike, B. W. Johnson and T. Okabe: Metall. Mater. Trans. A, 2008, vol. 39, pp. 171-180.
W. J. Boettinger, M. E. Williams, S. R. Coriell, U. R. Kattner and B. A. Mueller: Metall. Mater. Trans. B, 2000, vol. 31, pp. 1419-1427.
C.-C. Hung, G.-L. Hou, C.-C. Tsai and C.-C. Huang: Dent. Mater., 2004, vol. 20, pp. 846-851.
Y. Guilin, L. Nan, L. Yousheng and W. Yining: J. Prosthet. Dent., 2007, vol. 97, pp. 157-164.
K.-i. Suzuki, K.i Nishikawa and Siro Watakabe: Mater. Tran., JIM, 1997, vol. 38, pp. 54–62.
M.-G. Kim, S. Kim and Y.-J. Kim: Mater. Trans., 2002, vol. 43, pp. 745-750.
L. Seul, B.-J. Choi, J.-I. Youn, and Y.-J. Kim: in Proc. 10th Int. Symp. Liq. Met. Process. Cast., M.J.M. Krane, A. Jardy, R.L. Williamson and J.J. Beaman, eds., Springer, Cham, 2016, pp. 341–45.
P.C.G. Oliveira, G.L. Adabo, R.F. Ribeiro and S.S. Rocha: Dent. Mater., 2006, vol. 22, pp. 1098-1102.
D. Chan, V. Guillory, R. Blackman and K.-h. Chung: J. Prosthet. Dent., 1997, vol. 78, pp. 400-404.
A.R.F. Pieralini, F. Nogueira, R.F. Ribeiro and G.L. Adabo: J. Prosthet. Dent., 2012, vol. 108, pp. 51-57.
B. Ravel and M. Newville: J. Synchrotron Radiat., 2005, vol. 12, pp. 537-541.
R. Gaddam, B. Sefer, R. Pederson and M. L. Antti: Mater. Sci. Eng., 2013, vol. 48, p. 012002.
H. Kikuchi, M. Onouchi, K. Miyanaga, M. Wakashima, O. Okuno and M. Nishiyama: J. Dent. Mater., 2004, vol. 23, pp. 387-394.
C. Frueh, D. R. Poirier and M. C. Maguire: Metall. Mater. Trans. B, 1997, vol. 28, pp. 919-926.
H H. Bros, M. L. Michel and R. Castanet: J. Therm Anal., 1994, vol. 41, pp. 7-24.
M. Xu, S.N. Lekakh and V.L. Richards: Int. J. Metalcast, 2016, vol. 10, pp. 329-337.
S.S.d. Rocha, G.L. Adabo, G.E.P. Henriques and M.A.d.A. Nóbilo: South Braz. Dent. J., 2006, vol. 17, pp. 126–129.
K.-F. Lin and C.-C. Lin: J. Mater. Sci., 1999, vol. 34, pp. 5899-5906.
M. . Yan, W. Xu, M. S. Dargusch, H. P. Tang, M. Brandt and M. Qian: Powder Metall., 2014, vol. 57, pp. 251-257.
R. Montanari, G. Costanza, M. E. Tata and C. Testani: Mater. Charact., 2008, vol. 59, pp. 334-337.
A. I. Frenkel: Chem. Soc. Rev., 2012, vol. 41, pp. 8163-8178.
S. Enzo, L. Schiffini, L. Battezzati and G. Cocco: J. Less-Common Met., 1988, vol. 140, pp. 129-137.
S. Carvin: XAFS for Everyone, CRC Press, New York, 2013.
H.H. Wu, P. Wisesa and D.R. Trinkle: Phys. Rev. B 2016, vol. 94, p. 014307.
B. Ravel: J. Synchrotron Radiat., 2014, vol. 21, pp. 1269-1274.
Acknowledgments
This study was financially supported by Chulalongkorn Academic Advancement into its 2nd Century Project, Chulalongkorn University, Thailand. The authors would like to express their gratitude to the Center for Scientific and Technological Equipment (CSTE), Suranaree University of Technology for access to the XRD Measurement Facility. We thank the Synchrotron Light Research Institute (Public Organization), Beam Line #8 (BL8:XAS) and also BL8 staff, in Nakhon Ratchasima, Thailand for providing the XAS Facility. Boonrat Lohwongwatana acknowledges the support from the Advanced Materials Analysis Research Unit and the Biomedical Engineering Research Center, Faculty of Engineering, Chulalongkorn University. Chedtha Puncreobutr acknowledges the in-kind material support from Meticuly Co., Ltd. Atchara Khamkongkaeo acknowledges the support from Rachadapisek Sompote Fund, Chulalongkorn University.
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Manuscript submitted June 28, 2019.
Rights and permissions
About this article
Cite this article
Boonchuduang, T., Bootchanont, A., Klysubun, W. et al. Formation of Alpha-Case Layer During Investment Casting of Pure Ti and Ti-6Al-4V Using Comparative XRD and EXAFS Investigation. Metall Mater Trans A 51, 586–596 (2020). https://doi.org/10.1007/s11661-019-05541-1
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11661-019-05541-1