Fluidized Bed Heat Treating of a Magnesium-Rare Earth Alloy

The heat treating response of a magnesium-rare earth alloy that underwent rapid heating to the holding temperatures using a fluidized bed heat treating process was investigated. Cast tensile samples underwent various solution treating and aging times within the fluidized bed process, and resulting mechanical behavior was measured by uniaxial tensile testing. The measured heating rates were faster than conventional processes with the cast tensile samples heated to both solution and aging holding temperatures within three minutes. From the measured mechanical behavior, the optimum solution treating time within the fluidized bed was two hours, and this holding time is considerably less than that recommended for standard conventional heat treating. Microstructural analysis showed that the solute phase dissolved rapidly within the Mg matrix during solution treating that allowed for a significant reduction in holding times using the fluidized bed process.