退火变脆Fe75Si10B15金属玻璃的脆韧性转变

研究了机械研磨对退火变脆Fe_(75)Si_(10)B_(15)金属玻璃的弛豫过程,晶化行为及脆韧性转变的影响。发现退火变脆的Fe_(75)Si_(10)B_(15)金属玻璃,经不同时间机械研磨,Curie温度T_C逐渐回落,总的弛像焓ΔH_?逐渐回升。在DSC曲线上观察到明显的玻璃转变温度T_(g_1)和一个附加的宽放热峰T_(x_1),随着研磨时间的增加,T_(x_1),T_(x_1),T_C同步降低,与T_(x_1)对应的放热面积ΔH_(x_1)逐渐增大,并在片状粒子表面形成切变带以及与其对应的剪切带,玻璃在退火过程中失掉的韧性逐渐得到恢复。

BRITTLE-DUCTILE TRANSITION OF ANNEAL-EMBRITTLED Fe_(75)Si_(10)B_(15) METALLIC GLASS

Studies were made of the effect of mechanical pulverization on relaxation,crystallization and brittle--ductile transition of the anneal--embrittled Fe_(75)Si_(10)B_(15) metallic glass ribbon. Results show that the Curie temperature, T_c, decreases and the total enthalpy of relaxa-tion increases gradually with variation of pulverized time. DSC traces reveal an extra exothermicpeak, T_(x_1), and a distinct glass transition endothermic peak, T_(g_1), with increasing pulverizedtime, T_c, T_(x_1), and T_(g_1) decrease simultaneously, and the exothermic peak area correspondingto T_(x_1) increases gradually. The surface slip--steps of flaky particles and their corresponding shear are produced by pulverizing the pre--embrittled amorphous glass. The lost ductility of theglass may restore during annealing.