Research on the Mechanism of Damping Attenuation Behavior of alloys

摘要

A new phenomenon that the damping property dramatically decreased at differentrnisothermal temperatures was found in four different alloys (Mg-Zr, Fe-Cr, 316 stainless steel andrnporous Ti-Ni alloy), and Mg-Zr alloy was selected to systematically investigate the mechanismrnof the damping attenuation behavior. Firstly, the damping attenuation behavior at differentrnisothermal temperatures and isothermal intervals were studied by implementing differentrndamping measurements on Dynamic Mechanical Analyzer (DMA). Secondly, dislocationrnmorphologies of the damping specimen before and after isothermal-treated were observed byrntransmission electron microscopy (TEM) respectively. It is shown that the damping attenuationrnbehavior can be attributed to the tangle process of mobile dislocations in the alloy during thernvibration, which decreases the mobility of dislocation and the damping property.