Microstructure、Texture And Mechanical Properties Of Al-1%Si Alloy

Nanostructured and ultrafine-grained metals have superior mechanical propertiesover their coarse-grained counterparts. However, these materials always exhibit lowtensile ductility that limits their pratical application. Annealing is an important processto control and improve the mechanical properties of materials. Therefore, it is importantto investigate the evolution of microstructure, texture and mechanical properties of theannealing materials during annealing to optimize the annealing process and henceproperties.98%cold rolled Al-1%Si alloy was annealed at210℃for different time in thiswork. The evolution of microstructure, texture and mechanical properties of the materialduring annealing were studied by microhardness, electron channel contrast (ECC),electron backscatter diffraction (EBSD) and tensile testing. The relationship between themicrostructure and mechanical properties were also discussed. The main results include:①Nucleation occurs after annealing for20min at210℃and the volume fractionof recrystallized grains increases with the rising of annealing time. The material is fullyrecrystallized after annealing for300min at210℃.②The orientation of nuclei are random. After the recrystallization is almostcomplete, a random texture is developed and the volume fractions of cube and rollingtexture components are very low.③Strength decreases while ductility increases with increasing volume fraction ofrecrystallized grains. The elongation of>30%can only be obtained after the volumefraction of recrystallized grains is larger than30%.