Research on the electro-thermal coupling mechanism and uniformity of magnesium alloy foil in non-annealing electric rolling

• Analysis of electro-thermal coupling characteristics and mechanisms in the Non-Annealing Electric Rolling (NAER) Process: A three-dimensional electro-thermal coupled temperature field model was developed to analyze the electro-thermal coupling characteristics and mechanisms in the NAER process, with experimental validation confirming the model's accuracy. • Quantitative analysis of the influence of rolling parameters on temperature uniformity: The study provides a theoretical basis for parameter setting by quantitatively analyzing the impact of rolling parameters on the uniformity of temperature distribution. • Achievement of the Non-Annealing Electric Rolling production for magnesium alloy foil with good surface quality: The Non-Annealing Electric Rolling (NAER) process has been successfully applied to produce magnesium alloy foil with excellent surface quality, demonstrating the practical value of the Non-Annealing Electric Rolling (NAER) process. The non-annealing electric rolling (NAER) process is an innovative technology for the efficient production of magnesium alloy foil, which enables online plasticization and toughening. It significantly improves the uniformity of the transverse temperature distribution, reduces edge cracking, and minimizes the occurrence of strip breakage. However, the mechanism by which the electric field influences the transverse temperature distribution remains unclear. To address this, a three-dimensional electro-thermal coupling temperature field model was developed that integrates the interaction characteristics and coupling mechanisms of the electric and temperature fields. Compared with single-pass NAER experiments, the average relative error between calculated and measured values at the mill entrance is 2.20 %, and the root mean square error of the transverse temperature distribution is 3.48, confirming the model's high accuracy and reliability. To improve the uniformity of the transverse temperature, a simulation study was conducted to explore optimal process parameter ranges, providing a theoretical basis for parameter selection in NAER. Finally, a six-pass NAER experiment successfully produced magnesium alloy foil with a thickness of 0.099 mm without intermediate annealing, achieving a total reduction of 86.2 %. The surface quality of the final product was satisfactory.