Effects of Ultrasound on the Microstructures and Mechanical Properties of Cast-Rolling AZ31B Magnesium Alloy Strip

Abstract

The experiment of ultrasonic cast-rolling magnesium strip was carried out on the horizontal twin-roll cast-rolling machine with the ultrasonic pole used in the solidification. The microstructures of ultrasonic and general cast-rolling magnesium strip were characterized. The results showed that the cellular dendrite of the general cast-rolling magnesium strip was coarse, the grain structure was heterogeneous and the average grain diameter was between 50μm~60μm. However, the grain structure became more homogenize after the ultrasonic treatment for cast-rolling magnesium strip, the grain was refined and the average grain diameter was between 20μm~30μm. Besides, the mechanical properties test results show that the tensile strength, yield strength and elongation of the ultrasonic cast-rolling magnesium strip were increased by 22.85%, 49.78% and 123.06% than those of the general cast-rolling magnesium strip.