Acoustic study of texture in polycrystalline brass

Resonant ultrasound spectroscopy was used to measure the orthorhombic elast ic constants of rolled, polycrystalline plates of Cu, Cu-5% Zn, and Cu-15% Zn. The experimental results were fit to theoretical expressions to determi ne the orientation-distribution coefficients W-400, W-420, and W-440. These coefficients are related to texture (the nonrandom orientation of crystall ites). The experimental results were in good agreement with theory for the Cu and the Cu-15% Zn materials. The agreement was not as good for the more anisotropic Cu-5% Zn material, especially for the in-plane compressional co nstants C-11 and C-22. The ultrasonically derived W's were compared to thos e obtained from neutron measurements for the Cu-Zn alloys. Pole plots based on the two types of measurements, using W-400, W-420, and W-440, were in e xcellent agreement for the 15% Zn material, and in qualitative agreement fo r the 5% Zn material. The results support the idea that acoustic methods ca n be used to measure the low-order W's in polycrystalline materials. (C) 19 99 Acoustical Society of America. [S0001-4966(99)00505-0].