FeSiAl Based Alloy Of High Performance Soft Magnetic Powder Core

Soft magnetic composite materials are usually prepared through powder metallurgy process, and they are of much better magnetic properties over other materials. Since the21st century, smaller and better electronic devices are required due to the development of science and technology, which leads to higher requirement for magnetic powder cores. FeSiAl magnetic powder core is widely used because of its high resistance, low magnetic core loss, and low price.In this paper, we investigated the effect of the technologic procedure parameters on magnetic and mechanical properties of FeSiAl magnetic cores. We developed samples of better properties which could also be produced in production.The granularity of FeSiAl powders has a great influence on the material’s permeability and loss. We chose powders with different particle sizes and analyzed the size effect on the magnetic properties of magnetic core. After that, we prepared powders using10%of100mesh,80%of200mesh and10%of400mesh powders.Considering insulation a critical procedure of magnetic powder core preparation, we first prepare samples without insulation so as to investigate the influence of different types of bond solvent. After that, we add some mica and investigate the effect of quantity of bond solvent on magnetic and mechanic properties of samples. At last, we use mica as the main insulation to investigate the effect of its proportion on properties. It is found that high magnetic permeability and low core loss are got when we increase the proportion of bond and mica in a certain range. Specifically, samples with1.2%of mica and0.8%of resin are of the best magnetic properties.Compaction pressure is the basement to get high magnetic property and good strength in magnetic powder core preparation. Normally, higher pressure would improve the permeability and strength. However, too high pressure will do the opposite, which leads to defects and strain inside magnetic powder core. As a result, it’s important to find the critical pressure that insulation could afford. According to our experiments, the best compaction pressure is1887MPa.Annealing treatment is also an important process in preparation, through which the material could get higher magnetic permeability and lower core loss. It’s necessary to enhance the annealing temperature with the precondition that the resin is not burn down. In addition, one should control annealing time to make sure the strain in the magnetic powder has been fully released. It is found that the best annealing treatment temperature is650℃.