A new technology for diffusion bonding intermetallic TiAl to steel with composite barrier layers

Journal Article · Wed Jan 15 04:00:00 EST 2003 · Materials Characterization

DOI:https://doi.org/10.1016/S1044-5803(03)00122-0· OSTI ID:20748684

He, P; Feng, J C; Zhang, B G; Qian, Y Y

In this study, intermetallic TiAl and steel are diffusion bonded successfully by using composite barrier layers of titanium/vanadium/copper. The relationship of the bond parameters and tensile strength of the joints is discussed, and the optimum bond parameters were obtained. The reaction products and the interface structures of the joints were investigated by SEM, EPMA, and XRD. In this case, a dual phase Ti{sub 3}Al+TiAl layer and a Ti solid solution, which enhances the strength of the joint, are obtained at the TiAl/Ti interface. A formation mechanism at the interface of TiAl/Ti was proposed. The whole reaction process can be divided into three stages. In the first stage, Ti (Al{sub ss}) layer is formed at the interface TiAl/titanium. In the second stage, the continuous diffusion of Al atoms from TiAl to titanium leads to the formation of Ti{sub 3}Al, a TiAl+Ti{sub 3}Al layer is formed adjacent to TiAl. In the last stage, the thickness of each reaction layer increases with bonding time according to a parabolic law. The interface of TiAl/titanium/vanadium/copper/steel was free from intermetallic compounds and other brittle phases, and the strength of the joint was as high as 420 MPa, very close to that of the TiAl base. This method provides a reliable bonding method of intermetallic TiAl and steel.

• OSTI ID: 20748684
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Journal Issue: 1 Vol. 50; ISSN 1044-5803; ISSN MACHEX
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BONDING
COPPER
DIFFUSION
ELECTRON MICROPROBE ANALYSIS
INTERFACES
INTERMETALLIC COMPOUNDS
JOINTS
LAYERS
SCANNING ELECTRON MICROSCOPY
SOLID SOLUTIONS
STEELS
TENSILE PROPERTIES
THICKNESS
TITANIUM
VANADIUM
X-RAY DIFFRACTION