S Hosseini - School ofMetallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran, P.O. Box ۱۱۱۵۵-۴۵۶۳, Iran
S. A. A Akbari Mousavi - School ofMetallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran, P.O. Box ۱۱۱۵۵-۴۵۶۳, Iran
G Faraji - Department of Mechanical Engineering, University College of Engineering, University of Tehran, Tehran, P.O. Box ۱۱۱۵۵-۴۵۶۳, Iran

Parallel Tubular Channel Angular Pressing (PTCAP) is a recently developed novel intense plastic deformation method appropriate for fabrication ultrafine-grained and nanostructured cylindrical tube. This technique was applied to AZ31 magnesium alloy up to four passes at 250°c and the effects on the mechanical properties were studied. Observation analysis by OM showed that with increasing in number of passes, it has a significant decrease in grain size. Dynamic Recrystallization (DRX) can be an important factor for this grain refinement. The micro hardness and tensile test were carried out in PTCAP samples at different passes. With increasing the number of passes the value of the hardness (HV) was increased. The initial hardness in as-extruded reached to maximum value after 4 passes. The yield stress shows a decrease in PTCAP passes as compared to as-extruded condition. It can be related to texture softening that happens during the parallel TCAP. But the yield and ultimate strength increase with increasing the number of passes.

AZ31 magnesium alloy, Severe plastic deformation, mechanical properties