INFLUENCE OF HOT ROLLING ON FRACTURE BEHAVIOUR OF Al-Fe-V-Si ALLOY PREPARED BY HOT EXTRUSION OF RAPIDLY SOLIDIFIED POWDERS
热轧变形对快凝Al—Fe—V—Si粉热挤合金断裂行为的影响

The room temperature fracture behaviours of the alloy prepared by rapidly solidified Al-8.5Fe-1.3V-1.7Si powders under different deforming conditions have been investigated. The results revealed that the propagation mode of main crack related to the orientation of powder boundaries when the specimen fractured. For the specimen tensed along extrusion direction, the microcracks along rolling plane did not affect propagation of the main cracks; the microcracks along vertical section might lead to unusual fracture; the cross-section boundaries are ready to become the low energy propagation path for main crack. Hot rolling improved cohesion strength for boundaries along the vertical section and cross-section more than ones along rolling plane, resulting in the change of fracture mode at a certain deformation (30%). The different variation regularities for fracture strength and elongation relate to the fracture mode and follow-on deformation hardening. Correspondent: LI Songrui, (professor, Department of Materials Sciences and Engineering, Central South University of Technology, Changsha 410083)