Nano-indentation studies and macro-scale mechanical testing of vanadium modified BBN ceramics

摘要

The mechanical properties of the pure as well as vanadium modified BaBi_2Nb_2O_9 ceramics have been studied in macro and nano-scales using three different methods. Specifically for macro-scale, ultrasonic velocity and internal friction were employed to evaluate the Young modulus (E), whereas for nano-scale the nanoindentation method was a very useful tool to obtain the elastic modulus and hardness. These results reveal the strong influence of vanadium admixture on mechanical properties of the discussed material. In the case of modified ceramics the value of Young modulus increases, which is probably connected with the decreasing of the number of defects. Moreover, the described results show the significant differences in mechanical properties measured on nano and macro-scale. It is concluded that the knowledge of the mechanical properties of the ceramic material is complete only when we take into account both the macro and nano-scale.