The effects of thermomechanical processing parameters on elevated temperature behavior of a 6061 Al-Al2O3 metal matrix composite

Abstract

The effects of thermomechanical processing parameters on the elevated temperature behavior of a 6061 aluminum -- aluminum oxides metal-matrix composite (MMC) have been studied. The same processing parameters were employed with unreinforced 6061 AL to provide a comparison. These materials were both thermomechanically processed at either 350 C or 500 C using two rolling schedules. Both schedules involved a constant strain per pass. Subsequent mechanical tests were conducted at temperatures 200 to 500 C and strain rates ranging from (6.7E-3)/s to (1.3E-1)/s. The materials processed at 500 C exhibited higher strength when compared to those processed at 350 C for deformation temperatures below 350 c. Materials stabilized by annealing after completion of rolling displayed higher ductilities when compared to the as-processed materials, especially at lower testing temperatures. The peak ductilities of the MMCS occurred at testing temperatures near the prior rolling temperatures. Solution treatment prior to rolling and additional strains during rolling in excess of 2.5 appeared to have no effect on strength or ductility