Structural Effects of Heat Treatment Holding-Time on Dynamic and Damping Behaviour of an Fe-28Mn-6Si-5Cr Shape Memory Alloy

Abstract

The paper reports the structural effects of holding time period, during heat treatment, on the dynamic and damping behavior of a Fe-28Mn-6Si-5Cr (mass. %) shape memory alloy. After casting and hot rolling, solution treatment at 1050 oC was applied for five holding times, 2, 4, 6, 8 and 10 hours, followed by water quenching. The specimens were analyzed by scanning electron microscopy and X-ray diffraction which emphasized that only the 2-hours solution treated specimens contained ε-hexagonal close packed (hcp) martensite and experienced the highest internal friction value. These specimens were tested on a special device which transformed both tension and compression into tensile strain applied to the specimens and proved to be a promising solution for anti-seismic damper.

Keywords

• FeMnSiCr shape memory alloys
• martensite
• strain sweep dynamic mechanical analysis
• internal friction
• anti-seismic damper