Mechanical properties and microstructure evolution of 1050 aluminum severely deformed by ECAP to 16 passes

Variation of mechanical properties and microstructure evolution in 1050 aluminum processed by equal channel angle pressing are investigated using Route BC and up to 16 passes. Micro hardness and compression testing were used to evaluate mechanical properties, whereas electron back scattered diffraction (EBSD) was used to document the variation of cell size and misorientation angle with number of passes. The hardness and yield strength exhibited an instant increase by a factor of about 2.75 and 2.96, respectively, compared to the annealed state, after only the first pass. It was found that the cell size gradually decreased with number of passes and attained an average value of about 0.6 μm in the face plane (normal to the extrusion direction), and 0.85 μm in the flow plane (parallel to the extrusion direction) after the sixteenth pass. The average misorientation angle evolved in both the face and flow planes ended up to about 27° and 26°, respectively.