Mechanical behavior of AlN/Mo functionally graded materials with various compositional structures

In this paper, aluminum nitride (AlN) and molybdenum (Mo) were used for fabrication of AlN/Mo functionally graded materials by spark plasma sintering (SPS). In order to study the influence of microstructure on mechanical properties in AlN/Mo FGMs, the FGMs with different composition exponent p value were analyzed by indentation and bending test . The results showed that the specimens with p  < 1 exhibited a metal-rich graded structure comparing to specimens with p  ≥ 1. The radial bending and shear strength of AlN/Mo FGMs reached maximum when p  < 1, which are 369.78 MPa and 48.01 MPa respectively. Moreover, comparing with the porosity and the ceramic/metal interface, the distribution of the two components is the most important factor for improvement of bending and shear strength. The more the hard metal network content in the graded layer, the higher the bending and shear strength of AlN/Mo FGMs.