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Indexed by:期刊论文

Date of Publication:2021-03-05

Journal:JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T

Volume:9

Issue:6

Page Number:13206-13215

ISSN No.:2238-7854

Key Words:TiAl; Ti3SiC2; Growth kinetics; Interfacial microstructure; Amorphous intergranular films

Abstract:Investigations of the interfacial microstructural evolution, the growth kinetics, and the mechanical properties in the Al-doped joint can derive guidelines for the knowledge-based parameter optimization of dissimilar Ti3SiC2/TiAl joining process. The interfacial microstructural evolution, the growth kinetics of the Ti3SiC2/TiAl joints was greatly altered by doping Ti3SiC2 with Al. The interface in the Ti-3(Si0.94Al0.06)C-2/TiAl and Ti-3(Si0.91Al0.09)C-2/TiAl joints changed from gamma+alpha(2)/TiAl3 + Ti5Si3 + Ti5Si4/Ti3SiC2 to gamma+alpha(2)/TiAl2/TiAl3 + Ti5Si3 + Ti5Si4/Ti3SiC2, to gamma+alpha(2)/gamma/TiAl2/TiAl3 + Ti5Si3 + Ti5Si4/Ti3SiC2, and to gamma+alpha(2)/gamma/TiAl2/TiAl3 + Ti5Si3 +Ti5Si4/Ti5Si3/Ti3SiC2 as the bonding temperature and duration increased. The growth of the interfacial compound layer in the Ti-3(Si0.94Al0.06)C-2/TiAl and Ti-3(Si0.91Al0.09)C-2/TiAl joints followed the cubic law and was controlled by grainboundary diffusion. The Al was the mainly diffusion elements in the Al-doped joints, and its diffusion in the Ti-3(Si,Al)C-2 substrate and in the interfacial layer was both along the grainboundaries. The bonding activation energies for the Al-doped joints were about 180 kJ/mol, which were much lower than the value (225 kJ/mol) for the undoped Ti3SiC2/TiAl joint. The highest shear strength of the Al-doped joints was about 65 MPa and was about 23% higher than the value of the undoped joint. (C) 2020 The Author(s). Published by Elsevier B.V.