Continuous Strip Casting of Magnesium Alloy by a Horizontal Twin Roll Caster

摘要

This paper is concerned with the development of a strip-casting technology for manufacturing magnesium alloy sheets. The aim of the work is to establish a manufacturing process and technology to facilitate the economical manufacture of high-quality magnesium sheet alloys. Magnesium alloy AZ31B was used to investigate the appropriate manufacturing conditions for use in twin-roll strip casting. Temperatures of the molten materials and roll speeds were varied to find the appropriate manufacturing conditions. The effects of manufacturing conditions on possible forming were clarified in terms of roll speeds and roll gaps between upper and lower rolls. In addition, microscopic observation of the microstructure of the finished casting was performed. It was determined that a magnesium sheet of 2.5 to 3.5mm thickness could be produced at a speed of 20m/min by a horizontal copper roll caster. Mill stiffness and a method of predicting the cast sheet's thickness were investigated to determine the appropriate manufacturing conditions. It was also found that the cast magnesium sheet manufactured by roll-strip casting could be used for plastic forming if the appropriate wrought magnesium sheets were produced after the roll casting process.