Damping characterization of magnesium matrix composites prepared by in-situ synthesis technique
(State Key Lab of Metal Matrix Composites, Shanghai Jiaotong University, Shanghai 200030, China)
Abstract: Magnesium alloy reinforced with 8% TiC(mass fraction) is in-situ synthesized using remelting and dilution technique. Damping capacity of AZ91 alloy and magnesium matrix composites was examined using Mark IV dynamic mechanical thermal analyzer. The results reveal that the damping capacity of materials is independent of frequency, but dependent on strain. Damping capacity of materials increase when testing strain enhances, and there is strain peak at damping-strain curve of materials. There are two temperature peaks at damping-temperature curve of magnesium matrix composites under 140℃ and 250℃ respectively. The damping mechanism is explained by dislocation motion, interface slip and grain boundary slip.
Key words: magnesium matrix composites； damping characterization； damping mechanism