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测量了Fe、Zn和Al单晶,Fe-40Al、Zn-40Al合金以及冷轧Fe、Zn、Al和Zn-40Al合金的符合正电子湮没辐射多普勒展宽谱和寿命谱。实验发现,在二元Fe-40Al合金中,Al原子的3p电子与Fe的3d电子形成了局域的共价键,正电子与Fe的3d电子湮没概率较低。当Zn和Al原子形成Zn-40Al合金时,Zn原子和Al原子间主要以金属键结合。铸态Fe-40Al合金中的结构空位浓度较高,且存在开空间大的晶界缺陷。轧制铝的商谱明显低于单晶铝的商谱,冷轧Zn-40Al合金商谱略低于铸态Zn-40Al合金商谱,而单晶锌和轧制锌的商谱几乎重叠。Al、Zn金属和Zn-40Al合金经冷轧后,由于样品中产生了缺陷,而导致正电子平均寿命增加:轧制铝的增幅最大,轧制Zn-40Al合金增幅次之,而轧制锌的增幅最小。
The Doppler broadening spectrum and lifetime spectrum of positron annihilation radiation were measured for Fe, Zn and Al single crystals, Fe-40Al and Zn-40Al alloys and cold-rolled Fe, Zn, Al and Zn-40Al alloys. It was found that in the binary Fe-40Al alloy, the 3p electrons of Al atom formed local covalent bonds with the 3d electrons of Fe, and the probability of 3d electron annihilation of positron and Fe was low. When the Zn and Al atoms form a Zn-40Al alloy, the Zn atoms and Al atoms are mainly bound by metal bonds. The as-cast Fe-40Al alloy has a higher concentration of vacancies and a larger grain boundary defect. The commercial spectrum of rolled aluminum is significantly lower than that of single-crystal aluminum. The commercial history of cold-rolled Zn-40Al alloy is slightly lower than that of as-cast Zn-40Al alloy, while the commercial spectra of single-crystal zinc and rolled zinc almost overlap. After cold rolling of Al, Zn and Zn-40Al alloys, the average positron lifetime increased due to the defects in the samples: the increase of rolled aluminum was the largest, followed by the increase of rolled Zn-40Al alloy, while that of rolled zinc The smallest increase.