The Effects of Static Strain on the Damping Capacity of High Damping Alloys

Abstract

Influences of static strain on the damping capacity in Mn-based M2052 and Fe-6Al alloys were studied with the forced flexural oscillation method by using a dynamic mechanical analyzer (DMA). The static surface strain was applied on the 3-point bending specimens in the range of 1.0 × 10 −5 -2.0 × 10 −4 . The damping capacity of the M2052 alloy showed a continuous increase, but that of the Fe-6Al alloy showed a continuous decrease with increasing static strain in the range below 1.0 × 10 −4 . The variation of the damping capacity with increasing static strain was fitted with an exponential function, and the exponential index turned out to be 0.25 and −0.5 for the M2052 and Fe-6Al alloys, respectively. Static strains in the vicinity of 1.0 × 10 −4 caused the formation of a damping peak, which accelerated the increase of the damping capacity in the M2052 alloy, but softened the decrease of the damping capacity in the Fe-6Al alloy. A significant reduction of the damping capacity appeared at static strains above 1.0 × 10 −4 in both high damping alloys.

Study of damping capacity of Fe–5.4Al–0.05Ti alloy

“…The damping capacity of the Fee5.4Ale0.05Ti alloy continuously decreases with an increase in the static strain in the range 2.0e15 Â 10 À4 . These results are in agreement with the results for Fee15Cr, Fee6Al [47,48], FeeGaeAl [49], and Fee15Cre2.5Moe1.0Ni [40] ferromagnetic high damping alloys. The maximum strain amplitude ε max and the maximum damping capacity Q À1 respectively shift to higher and lower values with an increase of the static stress.…”

Effects of Si on Tensile Properties Associated with Deformation-Induced ε-Martensitic Transformation in High Mn Austenitic Alloys

“…The temperature dependence of Young's modulus obtained by DMA provides the transformation temperatures. 27,29,30) During the cooling process of the DMA, thermally induced ¾-martensite increases Young's modulus whereas the antiferromagnetic transition decreases it. The obtained temperature dependence of Young's modulus and the corresponding transformation temperatures are shown in Fig.…”

The Twinning Microstructure and Damping Behavior in Mn–30Cu (at%) Alloy

“…The principles of DMA method were described concretely in a previous work. 5) During heating the specimens at 0.05 K/s, vibration in the frequency of 0.1, 1 and 10 Hz is alternatively applied. As the result, Young's modulus and damping capacity (tan ) varying with the increasing temperature are obtained.…”