Hot forgeability and die-forging forming of semi-continuously cast AZ70 magnesium alloy

Semi-continuously cast AZ70 Mg alloy were studied at different temperatures and various strain rates in uniaxial tensile and compressive tests. The plastic diagram, the curves of deformation resistance and the relationship curves between deformation degree and mean grain sizes were determined. The possible hot-forging process parameters were subsequently confirmed. Based on these results and the presently used forging equipments and dies, a conventional forging experiment for a projectile head shell was performed on an oil hydraulic press with the capacity of 3 MN by directly utilizing semi-continuously cast AZ70 billet. The forged head shell possesses the desired microstructure and good combined mechanical properties with 30 wt.% saving in comparison with an Al alloy shell.