研究了不同温度（３００—６１０℃）退火后的Ｆｅ７３５Ｃｕ１Ｎｂ３Ｓｉ１３５Ｂ９合金初始磁导率μｉ与温度Ｔ的关系（μｉＴ曲线）．实验结果表明，μｉＴ曲线可划分为三种类型，其对应的退火温度分别为：Ｔａ≤４６０℃，４８０℃≤Ｔａ≤５８０℃，５９０℃≤Ｔａ≤６１０℃．分析了这三种类型的μｉＴ曲线对应的合金相结构，讨论了μｉ随Ｔ变化的原因． The relationship between initial magnetic permeability μi and temperature T (μiT curve) of Fe735Cu1Nb3Si135B9 alloy annealed at different temperatures (300-610 ℃) was studied. The experimental results show that the μiT curve can be divided into three types. The corresponding annealing temperatures are: Ta≤460 ℃, 480 ℃ ≤Ta≤580 ℃, 590 ℃≤Ta≤610 ℃. The phase structure of these three types of μiT curves is analyzed. The reason why μi changes with T is discussed.