Pitcheswara Rao et al. [5] observed

Pitcheswara Rao et al. [5] observed through optical micrographfor ZX11 alloy, the initial microstructure having the average graindiameter of 120 mm, while exhibiting in two phases TernaryCa2Mg6Zn3 at grain boundaries as the samples underwent at3000 and 3800 the recrystallized grains and average grain size isimproved, while the specimen at 2600 the lower temperatureinstability occurred and for 460 C high temperature region intercrystalline cracking regions are formed. Aibinm et al. [3], Bhushanand Kumar [4] observed through optical and SEM micrograph forthe AZ91 alloy processed by ECAP with 16 number of passesshowed the grain size of a-Mg matrix decreased and UFGmicrostructure formed while b- phase were completely refined tosmaller particles and homogeneously distributed. Jiang et al. [2]observed through optical micrograph for the ZE41A Magnesiumalloy processed through ECAP. The initial cast alloy consists of aMg grains which are distributed at the grain boundaries, as thenumber of ECAP passes increased from 8,16,60 the grain particlesare homogeneously dispersed. Gzyl et al. [1] observed throughoptical micrograph of AZ31B extruded rod and plate the extrudedbar is dominated by coarse grains and having small colonies ofsmall grains, where are for rolled plate the homogeneity isobserved with little amount of coarse grains. As the sample passedby I-ECAP through routes, the initial microstructure of the samplehaving equally distributed flat grains of different shapes, andundissolved particles are seen and for extruded bar is dominatedby coarse grains and having small colonies of small grains, whereasfor the rolled plate for different temperature and with additionalannealing contributed to grain refinement and homogeneous colonies of small grains are absent, tensile samples revealed shearbands parallel to shear plane and rolled plate after 6 number ofpasses with additional annealing temperature was increased thegrowth of grain size was seen