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对熔体急冷法制备的Fe43Co43Hf7B6Cu1非晶合金进行了200,300,400和500℃保温30min的退火处理,用正电子湮没寿命谱、X射线衍射、穆斯堡尔谱等方法研究了退火后试样的结构及结构缺陷变化.结果表明,在非晶合金的制备态,正电子主要在非晶基体相空位尺寸的自由体积中湮没,湮没寿命τ1为158.4ps,强度I1≥85%,另外有11.9%(I2)的正电子被非晶中的微孔洞(空位团)所俘获,湮没寿命τ2为397ps.在200,300,400℃退火时,结构弛豫导致τ1连续下降,在400℃,τ1约149ps,I1下降到80.8%,τ2降为352.9ps,I2增加到18.0%;当退火温度升高至500℃,非晶发生晶化,产生新的正电子俘获中心,I2急剧增加达26.7%.
The Fe43Co43Hf7B6Cu1 amorphous alloy prepared by melt quenching was annealed at 200, 300, 400 and 500 ℃ for 30 min. The structure of the sample after annealing and the structure of the annealed sample were investigated by positron annihilation lifetime spectroscopy, X-ray diffraction and Mossbauer spectroscopy The results show that positrons are mainly annihilated in the free volume of the phase vacancies of amorphous matrix in amorphous state, the annihilation lifetime τ1 is 158.4ps, the intensity I1≥85% and the other 11.9% (I2 ) Was trapped by the micropores (vacancy clusters) in the amorphous phase, and the annihilation lifetime τ2 was 397 ps. At 200, 300 and 400 ℃ annealing, the structural relaxation led to a continuous decrease of τ1. At 400 ℃, τ1 was about 149 ps and I1 decreased to 80.8%, τ2 decreased to 352.9ps and I2 increased to 18.0%. When the annealing temperature increased to 500 ℃, the crystallization of amorphous occurred, resulting in a new positron-trapping center with a sharp increase of I2 of 26.7%.