Effects of Mechanical Milling and FAST on Mg Powders: Microstructural Analysis and Mechanical Properties

Abstract

This study investigates the sintering mechanism of commercially pure Magnesium (Mg) using the Field Assisted Sintering Technique (FAST). Powder morphologies are in a vast variety of spherical to flake, as well as nano to fine grain as in powder size and mechanically milled (MM) between 0-108 hours. The MM'ed Mg particles were sintered by FAST with at 350-425℃ for 5-20min. Relative densities (93-99%) and compressive strength up to 369MPa were obtained from FAST’ed Mg samples depending on MM durations and particle geometries which significantly influenced the sintering mechanism. SEM and XRD analysis identified four distinct bonding and sintering mechanisms influenced by particle geometry, residual stress, and microstructure developed through mechanical milling. The combination of mechanical milling and FAST exhibited significant effects on the microstructural and mechanical properties of Mg powders, with the Mg36 sample displaying promising strength and hardness.

Keywords

• Mechanical milling
• Mechanical activation
• FAST
• Sintering mechanism
• Magnesium

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