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在Bi-2223相的生成过程中,氧起到非常重要的作用。对Bi-2223/Ag带材而言,氧能够透过银包套在超导芯与外部环境气氛之间进行交换,因而,超导芯处的氧与气氛中氧含量相近。而对于Bi-2223/Ag/Ni带材而言,外层的包套材料为镍,氧不能扩散通过镍包套。为了使氧能够在超导芯与环境气氛之间进行交换,将带材一侧的镍去除,为氧的扩散提供一个通道。这使得氧在Bi-2223/Ag带材与Bi-2223/Ag/Ni带材中扩散条件和扩散过程是完全不同的,超导芯的氧含量的变化规律也是不一样的,必然会对Bi-2223相的生成过程产生影响。实验结果表明,在单芯Bi-2223/Ag/Ni带材中,高的氧分压不利于Bi-2223相的生成。
Oxygen plays a very important role in the formation of the Bi-2223 phase. For Bi-2223 / Ag tapes, oxygen can be exchanged between the superconducting core and the external ambient atmosphere through the silver sheath so that the oxygen content of the superconducting core is similar to that of the atmosphere. For the Bi-2223 / Ag / Ni strip, the outer cladding is nickel and the oxygen can not diffuse through the nickel cladding. To allow oxygen to be exchanged between the superconducting core and the ambient atmosphere, the nickel on one side of the strip is removed, providing a pathway for the diffusion of oxygen. This makes the oxygen in the Bi-2223 / Ag tape and the Bi-2223 / Ag / Ni tape diffusion conditions and diffusion process is completely different, superconducting core oxygen content changes are not the same, will inevitably Bi -2223 phase of the impact of the generation process. The experimental results show that the high oxygen partial pressure is not conducive to the formation of Bi-2223 phase in the single-core Bi-2223 / Ag / Ni strip.