High Damping Capacity Of Fe-Mn Alloys

The damping behavior of thermal martensite and deformed for Fe-Mn alloys as well as the effects of cold rolling deformation, heat treatment and the condition on the damping behavior of Fe-Mn based alloys have been investigated systematically by means of thermal mechanical analyzer (TMA), scanning electron microscopy (SEM) and X-RAY diffraction. The micro梞echanism for high damping properties of martensite in Fe-Mn alloys has been discussedThe experiment results show that the damping capacity of Fe-Mn alloys increases slowly with the increase of strain amplitude at low strain amplitude and the fiction- strain is not liner; when the strain amplitude is up to a certain value, the damping capacity increases quickly with increase of strain amplitude at high strain amplitude and the fiction-strain is liner very well. The movements of twin interfaces and dislocations are responsible for the high damping properties of deformed martensite.Heat-treating temperature affects obviously the damping capacity of these alloys. As the heat-treating temperature rises, the damping capacity of Fe-Mn reaches peaks at 1000 for one hour followed by water cooling and decreases with further increasing of heat-treating temperatureThe damping capacity of martensite first increase and then decreasewith the increase of cold rolling deformation. The movements of interphase boundaries and moving ability are responsible for the high damping properties of the alloys.By studying the damping capacity of the Fe-Mn alloys at high temperature, the damping character and variation are made clear. As the testing temperature increase, the damping capacity of Fe-Mn first increase then decrease gradually. The damping characters of these alloys are still higher at 300.The tensile properties are investigated. The results indicate Fe-14Mn-0. 2C alloys possess the better mechanical property at 600 for one hour followed by water cooling. Its tensile strength(b) is 1019Mpa, and longation percentage is 15%. After all, with suitable heat treatment, Fe-Mn alloy possesses the highest damping capacity and good mechanical property.