Study on the Lubrication Characteristics at the Elevated Temperature in Hot Forging Test with Extruded AZ80 Mg Alloy

Abstract

This paper demonstrates the lubricant performance in T-shape hot forging of Mg alloys. This processes induces complex plastic material flow of the initial billet such as simultaneous compression and extrusion deformations. Five lubricants with different amounts of graphite are applied to the T-shape forging at temperatures of 300 and 350 °C. As the amount of graphite in the lubricant increases, the extruded depth gradually increases, which improves hot forgeability for Mg alloys. However, the lubricant performance decreases as forging temperature increases from 300 to 350 °C. As the punch stroke increases, forgeability is considerably influenced by the lubricant. Thus, the selection of lubricants in hot forging of Mg alloys is critical when plastic deformation is severe.