Microindentation of coarse-grained polycrystalline α-brass

Effects of the indent depth, the distance between the indent and the grain boundary, grain sizes, and crystallographic orientations on the microhardness of annealed coarse-grained polycrystalline alpha-brass were investigated using a Vickers indenter with indents much smaller than the alpha-brass grains (ranging from 80 mum to 550 mum). It is found that the microhardness of alpha-brass crystals shows a strong dependence on the indentation depth when it is smaller than 5 mum and a very weak dependence on both the distance between the indent and the grain boundary and the grain size when the indentation depth is about 5 mum and more. No significant dependence of the microhardness on the crystallographic orientations was observed in the fourteen grains of different orientations studied in this investigation.