Open-celled porous Cu prepared by replication of a new space-holder

• Rock candy particles were used as space-holders to prepare open-celled porous Cu.
• A relaxational internal friction peak was found at around 260 °C.
• The porous Cu has a significantly enhanced damping capacity compared with the solid Cu.
• Mechanisms of the internal friction peak and damping enhancement were discussed.

An open-celled porous Cu has been successfully prepared by using rock candy particles as space-holders. Resultant material exhibits uniformly distributed and interconnected pores. Results of damping test show that a relaxational internal friction peak arises at around 260 °C. Corresponding to the appearance of this peak the storage modulus has a softening valley. This peak has been ascribed to the sliding of grain boundaries under the applied stresses during damping test. It is also found that compared with the solid Cu, the damping capacity of the porous Cu has been significantly enhanced due to the effect of pores and the micro-plastic deformation in the Cu matrix.