The Effect Of Grain Size And Orientation On The Mechanical Property Of Copper

When the particle size of materials is in the nanometer level, the mechanicalproperties of materials change a lot. So it is necessary to study the mechanical propertiesof materials microscopically. In this article, nanoindentation tests were performed ondifferent grain-sized polycrystalline copper and different grain-orientationed singlecrystal copper to get the mechanical properties of materials.It was showed that the hardness of polycrystalline copper has obvious size effectwith respect to the depth of indentation, while the modulus is not very sensitive toindentation depth. For different grain-sized polycrystalline copper, hardness and elasticmodulus are also different. Along with the increase of grain size, hardness and modulusincrease in the beginning, then decrease. Single crystal copper also showed obvious sizeeffect. At the same depth, the hardness of (110) orientation is much higher than (100)orientation. With the increase of depth, the difference gradually decreases, and finallycomes zero. In addition, the hardness and the modulus of single crystal copper are bothsmaller than those of polycrystalline copper.This paper also investigates by the combination of nanoindentation test method andEBSD technology to analyze the indentation in the materials, so as to obtain theorientation of the indentation area.