对某厂生产的 R型变压器铁芯的材质、制造工艺流程及其对电磁性能的影响进行了全面分析。认为在所采用的低真空充氮退火工序中 ,因设备结构、工装和退火工艺不合理 ,炉内温度和气氛不均匀 ,使铁芯硅钢带出现局部氧化或渗碳现象而产生异常组织。这是铁芯电磁性能低下、合格率低的主要原因。作者提出了防止其产生的措施 ,并通过试验证明 ,低真空充氮退火适合 R型铁芯生产的技术要求 The R-type transformer core material, manufacturing process and its impact on the electromagnetic performance of a factory were analyzed. It is considered that in the low vacuum nitrogen annealing process adopted, due to the unreasonable equipment structure, tooling and annealing process, the temperature and atmosphere in the furnace are not uniform, so that the local oxidation or carburization of the iron core silicon steel occurs abnormally and the microstructure is abnormal. This is the core of the electromagnetic performance is low, the main reason for the low pass rate. The author put forward measures to prevent its occurrence, and proved through experiments that the technology of low vacuum nitrogen annealing for R-type iron core production