Abstract:
The objective of this thesis was to study effects of cyclic annealing on the microstructure of 1100 Aluminium after recrystallization. A two-zone furnace was constructed and the cyclic annealing was achieved by moving specimens between the two temperature zones. Total annealing time and dwelling time at each cycle in the range of 350- 450°c were the two main variables in this study. Optical micrographs and x-ray diffraction technique were used for microstructure comparison. Results show that cyclic annealing accelerated grain growth rate as evidenced by the fact that the total annealing time of 60 minute led to the mean grain size of 8-10% bigger than isothermal annealing, x-ray diffraction also revealed that among the crystallographic planes of (200), (220), and (311), the intensity of (220) peak was systematically reduced in samples that were 18 and 30 minutes cyclically annealed as compared to those that were isothermally annealed. Results from hardness test however did not indicate any difference between cyclic and isothermal annealing method.