Neutron Diffraction and Neutron Radiography Investigation into Powder Sintering of Ti/Al and TiH2/Al Compacts
Sintering behaviors of two types of powder compact, i.e., Ti/Al and TiH2/Al, under vacuum were studied using in situ neutron diffraction, in situ thermal dilatometric measurement, and ex situ neutron radiography. Their densification, microstructure, hydrogen concentration, and phase transformation features were compared. The results indicate that the predominant phase identified in the samples sintered from both compacts is γ-TiAl phase with minor Ti3Al phase. Dehydrogenation of TiH2 plays a decisive role in the sintering behavior and the resultant microstructure. In comparison with the Ti/Al compact, dehydrogenation occurring in the TiH2/Al compact leads to a higher level of densification and faster sintering kinetics.
GC gratefully acknowledges the funding from National Natural Science Foundation of China (Contract No.: 51604228) and the Fundamental Research Funds for the Central Universities (No.: 06500092). This study is also supported by State Key Lab of Advanced Metals and Materials, University of Science and Technology Beijing, P.R. China (No.: 2018-Z02). PC appreciates the financial support from Ministry of Business Innovation and Employment (MBIE), New Zealand. The authors also acknowledge the Australian Nuclear Science and Technology Organisation (ANSTO) for providing the neutron research facilities used in this study. The authors would like to thank the Australian Institute of Nuclear Science and Engineering (AINSE) Ltd. and ANSTO for providing funds (Nos.: P3430 and P4788) to enable us conduct the study on WOMBAT and DINGO.
- 5.A.P. Savitskii, N.N. Burtsev: Poroshkovaya Metallurgiya, 1983, vol. 3, pp. 24-9.Google Scholar
- 9.Z.Z. Fang, J.D. Paramore, P. Sun, K.S.R. Chandran, Y. Zhang, Y. Xia, F. Cao, M. Koopman, M. Free: International Materials Reviews, 2017, vol. pp. 1-53.Google Scholar
- 10.B. Liu, Y. Liu: 27—Powder metallurgy titanium aluminide alloys A2, in: Ma Qian, F.H.F. (Ed.) Titanium Powder Metallurgy. Butterworth-Heinemann, Boston, 2015, pp. 515-31.Google Scholar
- 23.I.A. Mwamba, L.H. Chown: Journal of the Southern African Institute of Mining and Metallurgy, 2011, vol. 111, pp. 159-65.Google Scholar
- 27.B. Viswanathan, S.S. Murthy, M.V.C. Sastri: Metal hydrides: fundamentals and applications, 1 ed., Springer1999.Google Scholar
- 35.G. Chen, N. Edmonds, P. Cao: International Journal of Powder Metallurgy, 2015, vol. 51, pp. 39-50.Google Scholar
- 40.M. Janssen, G.D. Rieck: Transactions of the Metallurgical Society of AIME, 1967, vol. 239, pp. 1372-85.Google Scholar