XRD investigation of thermostability of TiB2/Al deformation layer introduced by shot peening

The thermostability of 6351Al and TiB2/6351 Al during heat treatment was investigated utilizing X-ray diffraction. Domain size and microstrain were calculated by modified Warren-Averbach method and Voigt method, respectively. Results showed that the textures of both specimens were randomized by shot peening and did not appear again after all heat treatments. Domains had grown during heat treatments, and the growth of composite was slower than that of alloy. The microstrain of composite is easier to release than alloy. Higher density dislocation around reinforcements promotes recrystallization while further domain growth was retarded. The similar variation of microstrain and FWHM shows that the dominant factor to affect FWHM is microstrain. The thermostability of composite is higher than that of alloy. (c) 2007 Elsevier B.V. All rights reserved.