Hardness Modeling of Az81 Magnesium Alloy at DifferentElevatedTemperaturesand Strain Rates

The hot deformation behavior of an AZ81 magnesium alloy was investigated by hot compressive testing on aSantam thermal mechanical simulator in the temperature of both 200 and 250°C and in the strain rate range of 0.00 s-1,0.01 s-1,0.1s-1 . The relationships amonghardness, strain rateand deformation temperature were analyzed. Hardness was decreased up to 59% by increasing temperature from 200c to 250c and also it increased 4% with the increase of strain rate ranging from 0.001 s-1to 0.01 s-1 and 3% for 0.01 s-1to 0.1s-1 in bothtemperatures.Average ratio of hardness at both ends of sample to middle section was 1.3.

Keywords:

AZ81 Magnesium Alloy , Hardness , strain rate , the bulk compression forming , extrusion