Microstructure and mechanical properties of rapidly solidified Mg alloy powders compacted by magnetic pulsed compaction (MPC) method

Gas atomized Mg–Zn4.3Y0.7 (at%) alloy powders were consolidated by using a magnetic pulsed compaction (MPC) process, and obtained by rapid solidification not to lose the fine microstructure during the generally conducted thermal consolidation process. MPC is known as one of the most rapid pressing process with the GPa range. The effects of the discharging voltage and thermal pressure on the microstructure, hardness, density and compressive strength were investigated. The experimental results showed that the density increased with increasing the voltage although the sample MPCed still consists of pores especially between the powder boundaries even at the maximum pressure of this investigation. The density was improved further up to 96% to the cast value by the MPC at the maximum voltage. Uniform and fine microstructure formed in the alloy powders as atomized was almost maintained even after the thermal MPC.

Research highlights
► MPC method offers aviable alternative to the drawback of existing P/M methods.
► The R/S Mg powders maintained a fine microstructureduring the MPC at high temperatures.
► Thermal condition of 573 K to the max pressure of 1.6 kV resulted in forming the pore-less structure as well as increasing the density.