Characterization of high damping Fe-Cr-Mo and Fe-Cr-Al alloys for naval ships application

Abstract

The metallurgical basis for high damping in Fe-Cr-based alloys was investigated. Two alloys similar to VACROSIL-010 were studied, with compositions of 84.7 Fe-11.44 Cr-2.91 A1 and 84.8 Fe-11.65 Cr-2.92 Mo. The strain dependence of specific damping capacity (SDC) was evaluated using a modified version of the resonant dwell technique. Heat treatment variations were introduced by annealing in argon gas at temperatures between 950 C and 1100 C and then furnace cooling. Cantilever beam specimens were evaluated for SDC at their first three resonant modes (0-1,000 Hz) at room temperature. Changes in damping capacity were correlated with the results of tensile hysteresis testing and dilatometry. Keywords: Damping; Ship silencing; Ferritic stainless steels