In this article A15 compound wires other than Nb
3Ga and V
3Ga are described. Nb
3Al has better high-field performance and strain tolerance than those of Nb
3Sn. However, in the diffusion between Nb and Al, compounds richer in Al are predominantly formed. Moreover stoichiometric Nb
3Al is present at quite a high temperature approximately 2,000ºC. The rapid quenching from a high temperature produces the bcc phase supersaturated with Al, which can be transformed to nearly stoichiometric Nb
3Al by subsequent annealing. The liquid quenching process is successful to obtain high performance in Nb
3Al, Nb
3(Al, Si) and Nb
3(Al, Ge) through this route. Then a continuous Joule heating and quenching process has been developed, which produces long-length Nb
3Al wires with good homogeneity. A 19.5 T test magnet has been constructed by using the resulting wire. Moreover, high-field accelerator magnets are being developed using this wire. The continuously Joule heated and quenched Nb
3Ga wire shows an upper critical field of ~32 T at 4.2 K. Nb
3Ge exhibits the highest
Tc among A15 compounds studied so far. Long length Nb
3Ge tapes with high
Jc
have been fabricated through the continuous CVD process. Multifilamentary V
3Si wires have been fabricated by the bronze process, adjusting the overall V / Si molar ratio in the wire. The
Tc and especially B
c2 of the bronze-processed V
3Ge wire are significantly enhanced by the addition of Al to the V core. Nb
3Al wires are now available for practical use in addition to V
3Ga and Nb
3Sn. Nb
3Ga, Nb
3Ge and V
3Si compounds may keep high potential for future applications.
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