Affiliation:
1. Key Laboratory for Advanced Technologies of Materials The Ministry of Education of China Southwest Jiao Tong University Chengdu 610031 P. R. China
2. R&D Department Tairimei Precision Manufacturing (Yangzhou) Co., Ltd. Yangzhou City 225000 P. R. China
3. National Key Laboratory on Ship Vibration and Noise China Ship Scientific Research Center Wuxi 214000 P. R. China
Abstract
As a metal functional material, the Mn–Cu‐based alloys are regarded to be able to cope with the vibration and noise from machines. In particular, the as‐cast alloys often exhibit an excellent damping capacity, which is attributed to the Mn segregation in the alloys. Herein, to amplify the kind of segregation, a trace of Sn is added in as‐cast Mn–Cu–Al alloys. The phase structures of the as‐cast Mn–44Cu–1.5Al alloys are analyzed in detail through X‐Ray diffraction (XRD). The distribution characteristics of face‐centered cubic (FCC) phases and face‐centered tetragonal (FCT) phases are observed using electron backscatter diffraction (BSE). The alloys’ dynamic mechanical spectra and internal friction (IF) are measured using an inverted torsion pendulum device. It is found that the addition of Sn promotes the Mn segregation in the as‐cast Mn–44Cu–1.5Al alloys. A large amount of FCT phases appears in the dendritic trunks, enhancing the damping capacity of the alloys. In the meantime, the Sn atoms enhance the twin boundary mobility in Mn‐rich dendritic trunks. As a result, the alloy containing 1 wt% Sn has the highest damping capacity in the alloys.
Subject
Condensed Matter Physics,General Materials Science