FeNi-based Nanocomposite Soft Magnetic Alloy Magnetic and Mechanical Property Tailoring Through Flash Annealing

Tailoring details of thermal processing, including controlled heating rates and annealing time, plays a key role in enhancement of soft magnetic properties of amorphous and nanocrystalline soft magnetic materials. In particular, rapid thermal processing also known as flash annealing has potential for grain size refinement, tailoring phase identity, and tuning magnetic properties. This work explores the differences between conventional furnace annealing and isothermal annealing with flash annealing techniques for a range of detailed thermal processing conditions (temperature, time, cooling method) in an FeNi-based alloy. As compared to conventional annealing, flash annealing results in dominant FCC gamma FeNi phase with refined grains. Microstructural refinement due to optimized flash annealing showed improved soft magnetic properties with reduced coercivity and improved ductility for improved core manufacturing at scale.