摘要
The fracture behavior of fully lamellar binaryγ-TiAl alloys is extremely anisotropic with respect to the lamellar orientation.For the fully lamellar Ti-46Al-0.5W-0.5Si alloy,the existence of silicide clusters plays a critical role on the fracture behavior.In the present study,tensile test and three point bending test were performed at room temperature with the loading axis parallel and perpendicular to the lamellar orientation,respectively.To investigate the influence of silicide clusters on the initiation and propagation of cracks,the fracture surface and the cracks adjacent to the fracture zone of the specimens have been analyzed.Results show that the fracture process is related to the morphology and distribution of the silicide clusters.Crack preferentially initiates at and propagates along the interface of silicide andα 2 /γlamellar with the loading axis perpendicular to the length direction of silicide.While the silicide can prevent the propagation of cracks from running across with the crack growth direction perpendicular to the length direction of silicide.
The fracture behavior of fully lamellar binary γ-TiAI alloys is extremely anisotropic with respect to the lamellar orientation. For the fully lamellar Ti-46Al-0.5W-0.5Si alloy, the existence of silicide clusters plays a critical role on the fracture behavior. In the present study, tensile test and three point bending test were performed at room temperature with the loading axis parallel and perpendicular to the lamellar orientation, respectively. To investigate the influence of silicide clusters on the initiation and propagation of cracks, the fracture surface and the cracks adjacent to the fracture zone of the specimens have been analyzed. Results show that the fracture process is related to the morphology and distribution of the silicide clusters. Crack preferentially initiates at and propagates along the interface of silicide and a2/7 lamellar with the loading axis perpendicular to the length direction of silicide. While the silicide can prevent the propagation of cracks from running across with the crack growth direction perpendicular to the length direction of silicide.
基金
supported by National Natural Science Foundation of China(Grant Nos.50975060,50901025)
the National Basic Research Program of China(Grant No.2011CB610406)
the China Postdoctoral Science Foundation(Grant Nos.201104420,20090450840)
the Fundamental Research Funds for the Central Universities(Grant No.HIT.BRET1.2010008)
Scientific and Technological Project in Heilongjiang Province(Grant No.GZ09A206)