Mechanical property investigation of AlN/VN nanomultilayers with microindentation technique

Abstract In this paper, a two-step penetration method using microindentation technique is presented to investigate the mechanical properties of AlN/VN nanomultilayers, and this method is used to evaluate the relationship of hardness, elastic modulus and modulation period of AlN/VN multilayers. The results show that hardness and elastic modulus of AlN/VN multilayers unvaryingly increase as the modulation period decreases. The microstructure analysis shows that multilayer posses columnar polycrystalline growth both of VN and then of AlN layer at short modulation period. The maximum values of HV=33.4 GPa and E =377.8 GPa, respectively, are reached at the modulation period of 1.0 nm. This demonstrates that there exist superhardness and supermodulus effects in AlN/VN nanomultilayers.