1A METHOD FOR CRYSTALLOGRAPHIC TEXTURE INVESTIGATIONS USING STANDARD X-RAY EQUIPMENT

A fast and accurate method has been developed for measuring crystalline texture in homogeneous materials. The method uses a conventional powder x-ray diffractometer capable of θ scans. Two scans are recorded from the sample: first, a high resolution θ-2θ scan is obtained of a Bragg peak whose diffracting planes are normal to the preferred orientation direction; second, a θ scan is obtained using this peak. The θ scan contains the required texture information but the intensities must be corrected for defocussing and absorption to obtain the texture profile. The θ-2θ scan of the Bragg peak is used to make the defocussing correction, and first principles calculations are used to correct for absorption. The theory behind these corrections is presented here. The validity of the technique has been verified by making measurements on untextured alumina. Data obtained from Bi2Sr2Ca2Cu3O10 superconducting tape specimens with this technique are compared with texture data obtained with a four-circle diffractometer. I