The use of silicon-containing steel in the manufacture of transformer cores can save raw materials and greatly reduce the volume and energy consumption of the transformer. A forsterite film of stoichiometry Mg₂SiO₄ formed on the steel surface provides a certain degree of insulation and forms by reaction between the oxides in internal oxidized zone and a deposited MgO coating during high-temperature annealing. In this work, the morphology evolution of internal oxidized zone and the forsterite film on the steel surface are studied when the arrangement methods for silicon steel and annealing atmosphere are different, then the relationship of morphology between internal oxidized zone and forsterite film is explored. Results showed that the morphology of forsterite film on the steel surface is closely related to the morphology of internal oxidized zone. Metallic iron particles exist in the forsterite film when an iron layer exists in the surface of internal oxidized zone.

使用含硅钢制造变压器铁芯，可以节省原材料，大大降低变压器的体积和能耗。化学计量比为 Mg ₂ SiO _{4 的}镁橄榄石薄膜在钢表面形成的 MgO 提供了一定程度的绝缘，并通过高温退火过程中内部氧化区的氧化物与沉积的 MgO 涂层之间的反应而形成。本工作研究了不同硅钢的排列方式和退火气氛时钢表面内氧化带和镁橄榄石膜的形貌演变，进而探讨了内氧化带与镁橄榄石膜的形貌关系。结果表明，钢表面镁橄榄石膜的形态与内部氧化区的形态密切相关。当内部氧化区表面存在铁层时，镁橄榄石膜中存在金属铁颗粒。