Shear strength and fracture characteristics near the interface of diffusion bonding of Fe3Al/Q235 dissimilar materials

In this study, Fe3Al intermetallic and Q235 steel were jointed by the vacuum diffusion bonding.The shear strength of the Fe3Al/Q235 interface was analyzed and the interfacial fracture morphology was observed by means of scanning electronic microscope (SEM).The experimental results indicated that the fracture location was on the Fe3Al side, and the shear rupture morphology was the cleavage characteristics with little toughness fracture.Most micro-cracks propagated along the interface near the Fe3Al side and sometimes leaned to the center of the interface.The Fe3Al/Q235 diffusion bonding joint with excellent interface combination and the sufficient shear strength (112 MPa) can be obtained when the heating temperature was 1060 • C, the holding time was 45-60 min and the pressure was 12-15 MPa.K e y w o r d s : diffusion bonding, interface, shear strength, fracture morphology