Static and Cyclic Deformation of Commercially Pure Al Processed by Equal-Channel Angular Pressing Using Two Routes

In the present investigation, annealed billets of commercially pure Al (1050) with coarse-grained microstructure of 0.6 mm were ECAPed through a die with an internal angle of 90 degrees using two routes A and B-C. The samples were processed up to four passes using both routes. The change in the processing route results in the change of the shear plane, and consequently the change in the produced microstructure. The microstructure study was conducted on the extrusion direction and the shear plane. The cell size, misoriention and the fraction of high angle boundaries were determined by using electron back scattered diffraction (EBSD). A study of mechanical behavior was conducted by cutting tensile and compression specimens from the ECAPed specimen in the extrusion direction to study the effect of processing route and the number of passes on the deformation characteristics. Enhanced strength was observed but with anisotropic behavior between tension and compression. Cyclic deformation under load control (HSF) was also performed and the S-N curves were established as a function of number of passes and processing route. The fractography of fractured tensile specimens was also investigated.