Papers by Keyword: Mg Chips

Abstract: Mg alloy chips produced by machining processes are fine and active, and thus difficult to recycle by melting. The treatment of Mg chips is one of the concerns for expansion of the application of Mg alloys. Therefore, suitable processing for Mg chips is necessary. Mg alloys have the disadvantage of poor corrosion resistivity, and high reactivity with water, leading to the hydrogen and Mg hydroxide. This hydrolysis reaction is enhanced by the presence of NaCl in water. In this study, hydrogen was produced by the hydrolysis reaction of Mg chips generated by machining and seawater. Furthermore, ball milling was performed to enhance the formation of hydrogen. The hydrolysis reaction combined with the ball milling produced 795mL of hydrogen for 1g of Mg chips after 120 min. However, only 180 mL of hydrogen was obtained by the reaction without ball milling; a notable improvement in hydrogen formation was observed. A similar result was obtained for AZ91 chips. It is believed that the combined process of hydrolysis and ball milling is useful for the production of hydrogen with the disposal of Mg chips.

Abstract: Machined AZ31 alloy chips were consolidated by hot-pressing and then hot-extrusion at 300 °C, and their workability was evaluated. The consolidated sample has a fully dense microstructure with fine equiaxed grains. The　compression and backward extrusion tests reveal that the consolidated AZ31 chips have a good workability at above 200°C.　It is said that the recycled AZ31 alloy by hot-extrusion of the chips is suitable for forging materials and the process is useful for the recycling of Mg chips.