تأثير درجة حرارة التعتيق و المعالجة-الحرارية الميكانيكية في الخواص الميكانيكية لمواد متراكبة(Al –Mg –Si)‎ Al2O3)‎

Abstract EN

This work is focusing on studying the effect of heat treatment and thermo mechanical process on microstructure and mechanical properties of metal matrix composite , based on (AL-Mg- Si) alloy reinforced by 10 of Al2O3 of particle size (< 53 um ) , and the system was prepared by stir-casting technique .

Microhardness measurement had revealed that the best aging time for the prepared composite system is about (9) hours which are higher than the needed time for the reference cast alloy.

Microstructure examination had shown that thermomechanical treatment had led to the refinement of Al2O3 Particles and their redistribution in the matrix.

Tensile test had shown that the yield stress and maximum strength of the thermomechanical treated composite system were higher as compared to the reference cast alloy composite at all deformation ratios percentages .

This improvement in mechanical properties was attributed to the refinement of Al2O3 particles in the matrix and grain boundaries, which behave as obstacles against the grain growth.

The mathematical analysis of tensile test results, showed that the ultimate tensile strength value was decreased as deformation temperature increased, and it followed the relationship.

σu= 870*T -0.299225{1 – 1.65( E٪)}