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采用Ｘ射线衍射和正电子湮没多普勒展宽测量相结合，研究了纳米晶态材料Ｆｅ７３．５Ｃｕ１Ｎｂ３Ｓｉ１３．５Ｂ９的结构随退火温度的变化。实验结果表明：急冷非品样品在４８０℃开始明显晶化，基体中析出体心立方结构的α－Ｆｅ（Ｓｉ）固溶体。随着退火温度的升高，非晶漫射峰不断减弱，而晶态相的衍射谱逐渐增强。进一步计算对衍射谱的分离，给出了品化分数和非晶相平均原子间距随退火温度的变化规律。正电子湮没实验证实了约５５０℃退火时样品内出现以Ｎｂ、Ｂ原子为主的晶界非晶相，Ｓ参数随退火温度的变化与非晶相平均原子间距随退火温度的变化规律一致。
X-ray diffraction and positron annihilation Doppler broadening measurement were used to study the structure of nanocrystalline Fe73.5Cu1Nb3Si13.5B9 with the annealing temperature. The experimental results show that the quenched non-product sample begins to crystallize obviously at 480 ℃, and the α-Fe (Si) solid solution with body-centered cubic structure is precipitated in the matrix. With the increase of annealing temperature, the amorphous diffuse peaks continue to diminish while the diffraction spectra of crystalline phases increase gradually. The separation of the diffraction spectrum was further calculated, and the law of the variation of the atomization fraction and the average atomic distance of the amorphous phase with the annealing temperature was given. The positron annihilation experiments show that Nb and B atoms are the main grain boundary amorphous phases in the sample annealed at about 550 ℃. The variation of the S parameter with the annealing temperature and the average atomic distance of the amorphous phase change with the annealing temperature.