Evolution of magnetic properties and microstructure of high-silicon steel during hot dipping and diffusion annealing

Summary form only given. Electrical steels with high silicon content (up to 6.5 wt.%Si) are difficult to process by conventional metallurgical routes: ordering phenomena make the material too brittle to be cold rolled. A hot dipping and diffusion annealing process appears to be an alternative production route to obtain steel with a high silicon and aluminium content avoiding rolling problems. Surface alloying with Si and Al is achieved on a conventional steel substrate by hot dipping in a hypereutectic Al-Si-bath followed by a diffusion annealing treatment in order to obtain a sufficient amount of Al and Si in solid solution over the thickness.