The density of magnesium-zinc (Mg-Zn) soft magnetic ferrite cores directly affects magnetic permeability and eddy current losses. Excessive internal pores within the green body reduce the electromagnetic performance of the magnetic material, while high-purity magnesium oxide can enhance the sintering density of Mg-Zn soft magnetic ferrites. Messi Biology’s specialized magnesium oxide for magnetic materials serves manufacturers of various high-frequency soft magnetic ferrite cores.
After Mg-Zn ferrite powder is pressed into a green body, gaps exist between the particles. During high-temperature sintering, solid-state reactions drive particle rearrangement, expel pores, and achieve densification. The addition of high-purity magnesium oxide acts as a sintering aid, lowering the activation energy of the system, promoting particle boundary diffusion, accelerating pore expulsion, and increasing the density of the core after sintering. A dense magnetic core features fewer internal pores, resulting in less obstruction to magnetic domain rotation, which helps achieve higher magnetic permeability while reducing eddy current losses caused by pores.
Magnesium oxide regulates grain growth during the sintering process, forming a uniform fine-grained structure. A fine-grained structure makes it easier to achieve overall densification and reduces large-sized closed pores. Large grains easily form large, difficult-to-expel pores, which lower the green body density. Messi Biology’s magnesium oxide powder features a fine particle size, good dispersibility, and uniform mixing, allowing it to function simultaneously throughout the entire green body. This ensures uniform density across all parts of the magnetic core and prevents localized looseness.
Impurities can generate secondary phases during the sintering process, trapping pores and hindering densification. Messi Biology strictly controls alkali metal and heavy metal impurities in its products to minimize secondary phase generation and ensure the smooth progression of solid-state reactions. The powder’s reactivity is tailored to the ferrite sintering temperature—avoiding abnormal grain growth caused by excessive reactivity, or a lack of sintering-aid effects due to insufficient reactivity—thus achieving a balance between density and microscopic grain size.
High-density Mg-Zn soft magnetic ferrite cores exhibit higher mechanical strength, making them less prone to edge chipping or breakage during core grinding and assembly processes, thereby improving the yield of finished products. Messi Biology can tailor magnesium oxide powders to customers’ kiln processes and core specifications, assisting in optimizing sintering processes and enhancing the overall quality of Mg-Zn soft magnetic ferrite products.