Morphology and damping characteristics of woodceramics

Woodceramics has attracted more and more attention as ecomaterial at low cost in recent years. The purpose of this paper is to investigate morphology, damping characteristics of woodceramics and relationship between them. The experimental results reveal that pores in woodceramics can be divided into macropores, micropores and nanopores according to their dimensional size. Macropores are the majority of interconnected pores while most micropores are closed pores. Based on formation process, nanopores are supposed to consist of isolated nanopores and dendritic nanopores. Woodceramics exhibits significant damping gains, especially at room temperature, higher strain amplitude and higher vibration frequency. The values of damping capacity increase with vibration frequency and strain amplitude, decrease with testing temperature. Macropores and some nanopores have little but micropores and some other nanopores have much contribution to damping properties of woodceramics. The possible damping mechanisms of woodceramics at normal temperature are defect damping and thermoelastic damping; at high temperatures, interface damping is likely to responsible for the majority of the damping of woodceramics.