Research on hot-pressing technology of ferrite hard magnetic materials of high performance

Cheap iron scale from the steel-rolling industry and technically pure SrCO₃ were used as raw materials. Hot-pressing technology was adopted for the sintering of finished products. Samples were subjected to a 50-100-kg/cm² pressure, and the deformation degree was controlled within the range of 50-60%. If the hot-pressing temperature and duration were properly selected for the samples with 25-mm diameters, (BH)_max of 4.80 MGOe and density of 5.03 g/m³ could be reached after hot pressing. When the diameter of samples with a width of 53 mm was increased to 72 mm, the (BH)_max was 4.30 MGOe. In comparison with related technology of materials of high performance, high density, and high orientation degree, there were three pronounced advantages, i.e., cheaper raw materials, larger sample size, and lower pressure of hot pressing. Mass production could be conveniently achieved by this technology