Effect of initial texture on deformation behavior of AZ31 magnesium alloy sheets under biaxial loading

Deformation behavior of an AZ31 Mg alloy under a biaxial loading has been studied in relation to the initial texture developed during a prior hot-rolling process. Sheet specimens were thus prepared from a hot-rolled plate in the RD-TD planes (RTD) and ND-TD planes (NTD) to examine the effects of initial texture. Biaxial dome forming tests were then carried out under the punch speed of 0.1 mm/s at room temperature (RT), 100 degrees C, and 200 degrees C to obtain punch load vs. displacement curves during dome-forming tests. Different twin modes were observed under a biaxial loading at RI, viz. {1 0 (1) over bar 1} compression twins and {1 0 (1) over bar 1}-{1 0 (1) over bar 2} double twins in RID specimens, while {1 0 (1) over bar 1} compression twins generated through the rotation of {1 0 (1) over bar 2} extension twins developed earlier in NTD specimens. Formability of NTD sheets was observed to increase more rapidly compared to that of RID specimens as forming temperature was raised, which might be accounted for by reduced critical resolve shear stresses (CRSS) of prismatic slips due to their higher Schmid factor values. (C) 2012 Elsevier By. All rights reserved.