机械合金化Nb-Al非平衡相中Nb3Al超导体析出机理研究

项目名称： 机械合金化Nb-Al非平衡相中Nb3Al超导体析出机理研究

项目编号： No.51302224

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 一般工业技术

项目作者： 潘熙锋

作者单位： 西北有色金属研究院

项目金额： 25万元

中文摘要： 与Nb3Sn相比，Nb3Al具有非常高的超导转变温度、上临界场和临界电流密度，以及优良的应力-应变容许特性，因此在高场超导磁体应用上有着巨大潜力。由于成相条件苛刻，目前高性能Nb3Al超导体须通过2000℃快热快冷得到晶粒细小的非平衡Nb(Al)ss过饱和固溶体，以及低温退火获得。本项目提出利用机械合金化制备Nb-Al非平衡相，结合粉末装管法和低温热处理制备Nb3Al线材路线。通过前期研究，我们成功制备了首根机械合金化Nb3Al超导线材，但由于缺乏对Nb3Al相形成过程研究，制备的超导体性能仍然较低。因此，本项目拟利用高分辨透射电镜和原位中子衍射等手段，开展机械合金化过程中Nb-Al非平衡相微观结构演变规律以及Nb3Al超导相析出机理的研究；并通过合金元素添加调节Nb3Al相的析出，以及超导体的晶粒连接和磁通钉扎机制；解决机械合金化手段制备高性能Nb3Al超导材料过程中的关键基础科学问题。

中文关键词： 低温超导线材；A15超导体；Nb3Al；机械合金化；临界电流密度

英文摘要： Due to with excellent Tc, Hc2 and Jc properties as well as good strain-stress tolerance, Nb3Al superconductor is thought as a very promising candidate at the high-field superconducting magnets application. However, because of its phase formation conditions limit, Nb3Al superconductor with good performance must be prepared by the rapid heating and quenching approach up to 2000 ℃ for obtaining metastable Nb(Al)ss supersaturated solid solution with fine grains, and then Nb3Al phase precipitates after a low-temperature heat-treatment. In this project, it was proposed to develop high-performance Nb3Al wires by using mechanical alloying method to make metastable Nb-Al nonequilibrium phase and with the powder-in tube and low-temperature annealing process. By our previous efforts, the first mechanical-alloyed Nb3Al superconducting wire was successfully fabricated; but since the formation mechnism of Nb3Al phase kept unknown,its superconducting propeties was still low. Therefore, this project aims to clarify the microstructure evolution process of metastable Nb-Al nonequilibrium phase and the precipitation mechanism of Nb3Al superconducting phase by high-resolution transmission electron microscope and in-situ neutron diffraction method,and also researches the role of the added alloying-elements in adjusting the precipita

英文关键词： Low-teperature superconducting wire；A15 superconductor；Niobium three Aluminium；mechanical alloying；critical current density