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许多A-15相材料是重要的实用超导材料。由于超导转变温度是材料性能的重要指标,因此人们较注重研究如何提高A-15相材料的临界温度。有许多作者预言A-15相Nb_3Si的Tc可高达25—35K,有的作者也指出在高压下可以合成A-15相Nb_3Si。 但是多年来一直未能获得A-15相Nb_3Si,原因是Nb和Si的原子半径比r_Nb/rsi不满足A-15相的稳定条件。只是近年来才用电子束蒸发淀积,射频溅射,化学气相淀积法合成亚稳相A-15结构Nb_3Si,但Tc均不高,约为7—9K。有人报道用爆炸法
Many A-15 phase materials are important practical superconducting materials. As the superconducting transition temperature is an important indicator of material properties, people pay more attention to how to improve the A-15 phase material critical temperature. Many authors predict the Tc of Nb_3Si phase A-15 can be as high as 25-35K, some authors also pointed out that under high pressure can be synthesized A-15 phase Nb_3Si. However, the Nb-3Si phase A-15 has not been obtained for many years because the atomic radius ratio r_Nb / rsi of Nb and Si does not satisfy the stable condition of the A-15 phase. Only in recent years, electron beam evaporation deposition, radio frequency sputtering, chemical vapor deposition synthesis metastable phase A-15 structure Nb_3Si, but Tc are not high, about 7-9K. It was reported that the explosion method