ガスアトマイズAZX912マグネシウム合金粉末の着火性および積層造形性

抄録

The relationship between the flammability and ignition of magnesium alloy powder for additive manufacturing prepared by the gas atomization method was investigated. It was found that the AZX912 magnesium alloy powder does not burn. Therefore, the powders with the average particle size of about 100 μm, which were sieved to 75-150 μm, were additively manufactured by the PBF method. The microstructure of the additively manufactured body consisted of finer dendrites than the atomized powder, and the calculated cooling rate was on the order of 10⁴ to 10⁷ °C/s. Next, the influence of the laser conditions on the microstructural changes of the additively manufactured body was investigated. It was found that the hot crack area percentage decreased when the laser energy density was in the range of 110-170 J/mm³. Furthermore, a fine microstructure without defects was obtained even after HIP treatment at 450°C and 98 MPa for 6 hours. This is due to the cooling rate after laser melting during the additive manufacturing.