Technological developments in amorphous and nanocrystalline soft magnetic ribbons with high saturation induction via patent analysis

The global development trend and key technologies of amorphous and nanocrystalline soft magnetic ribbons (ANSMR) were analyzed and assessed based on the patent documents of ANSMR with high saturation induction. It provides the annual patent application trends, top five application countries, distribution of ANSMR technologies, patentee types, and technology roadmap. The results show that China and Japan file the greatest number of ANSMR patents. The countries with the most active patent applications in the past three years were China, Korea, and Japan. Unlike patents in foreign countries mainly applied by enterprises, patents in China were mainly filed by enterprises and universities. As evidenced by international patent classification (IPC) and technology evolution, the ANSMR technologies mainly focus on alloy composition, ribbon preparation, and application technology. The composition design tends to be FeCuSiBPC, FeCuSiBPNbM, and FeCoCuSiBP alloys with higher B s over 1.8 T. The preparation technology tends to have wider and thinner ribbons, multi-step field annealing, and fast annealing to reduce core loss. The application technology tends to higher-frequency and high-efficient situations such as wireless charging, high-frequency transformers, shielding, and motors. The technological development of the ANSMR trends to higher B s and wider ribbons, as well as high-efficient and high-frequency applications.