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为研究Nb3Sn超导材料的A15相成相动力学,设计并制备了四组单组元内锡法(MEIT)超导线.这四组MEIT导线设计了不同的Sn/Cu比,并在一组导线中合金化掺杂了1at%Zr,,所有导线样品先经历210℃/50hr+340℃/25kr的Cu-Sn合金化热处理,然后进行A15相成相热处理.选择四种反应温度:650℃,675℃,700℃和725℃,以研究成相热处理温度和时间的影响.用SEM技术测定所有热处理样品的A15相层厚,然后对不同温度下的热处理时间作图,并进行非线性拟合.所得结果表明四种因素促进了A15相的增长:增加反应温度,延长反应时间,增大Sn/Cu比率和合金化掺杂zr;内锡法Nb,sn超导线材的成相动力学服从Yn=K(T)t变化关系,A15相生长指数n值受热处理温度和Zr掺杂的影响.“,”For investigating A15 phase formation kinetics of Nb3Sn superconductors four sets of mono-element intemal-Sn(MEIT)wires were designed and fabricated,which have different Sn/Cu ratio and 1at%Zr addition in one wire.All samples underwent a 210℃/50hr +340℃/25hr thermal treatment for Cu-Sn alloying prior to the A15 phase formation heat treatment.Four reaction temperatures of 650℃,675℃,700℃and 725℃ were chosen to study the temperature influence with different time durations.Through SEM the heat-treated samples were examined for A15 layer thicknesses which were then plotted versus heat treatment time at different ternperatures and non-linearly fitted.The obtained results demonstrate that the A15 phase growth is promoted by four factors:reaction temperature elevation,reaction time exten-sion.Sn/Cu ratio enlargement and the alloyed Zr addition.The phase formation kinetics of internal-Sn Nb3 Sn superconducting wires is in agreement with Yn=K(T)t relation and the A15 growth exponent n is affected by HT temperature and Zr alloying.