Electromagnetic Twin-Roll Casting of Aluminium Alloy Sheets: An Overview

Aluminum (Al) alloys have been the most popular choice in various applications to achieve an optimum strength-to-weight ratio. Al sheets/strips products can be economically produced by the twin-roll casting process. However, the cast strips possess several cast defects, which degrade the quality of the products. A detailed study on as-cast TRC strips, i.e., types of defects, reasons of occurrence, and possible remedies is reported and discussed. It has been found that, with the help of an external electromagnetic field, a better-quality Al sheet can be manufactured by a TRC machine. The effects of different types of EMFs on the segregation and grain refinement of TRC Al alloys have been studied and compared. The requirement of EMF depending on various casting factors, like pouring temperature, rolling speed, and alloy composition, is presented and discussed. Various casting parameters and EMF types, and the amount that influences the macro-segregation and grain refinement of various Al alloys, have also been studied.