DAMPING PERFORMANCE AND MECHANISM OF HIGH STRENGTH ALUMINUM ALLOY PREPARED BY RAPIDLY SOLIDIFIED/POWER METALLURGY PROCESS

The investigation of damping property, microstructure and damping mechanism of High Strength Aluminum Alloy (HSAA) prepared by rapid solidified/powder metallurgy (RS/PM) process were conducted by means of Dynamic Mechanical Thermal Analyzer (DMTA) and Transmission Electron Microscopy (TEM) in the paper. The damping capacity (Q-1) of the HSAA was (0.5~3.1)×10-2 in the temperature range of 20~250°C, reaching to the level of high damping alloys. It was found that grain boundaries in the alloy became clear and sharp in high temperature and contributed to the total damping capacity. The analysis results show that at low temperature, the main internal friction mechanism was dislocation damping which was induced by large extrusion deformation, while in the high temperature region, the influence of interface damping increased gradually.