Effect of nanodiamond particle sizes on damping properties of ZK60 magnesium matrix composites

The aim of the research is to ensure that the material has functional mechanical properties as well as high-damping value. The microstructure, elemental composition, second phase distribution and interface structure of the Mg-based composite with different particle sizes were characterized by Optical Microscope(OM), X-Ray Diffractometer(XRD), Scanning Electron Microscope(SEM), Transmission Electron Microscope(TEM) and Energy Dispersive Spectrometer (EDS). The mechanical and damping properties of the ZK60 magnesium matrix composites were investigated an Instron5982 universal tester and Dynamic Mechanical Analysis (DMA). The results indicate that nanodiamond(ND) can disperse well in the composites. The elastic modulus of composite can reach 9.9 GPa after reinforcement phase being added. Under certain conditions,the damping value can reach beyond 2.5 × 10 –1 , which is 117% of other composite. High-temperature damping depends on grain boundary slip and interface slip. The interfacial damping depends on the difference in the incoherent interface and thermal expansion coefficient between the nanodiamond and ZK60 matrix to slip and improve the damping value.