摘要
金属铌是超导线材重要的阻隔层材料,铌板通过卷筒焊接后,装入Nb3Sn、NbTi等超导芯部材料,经过挤压、集束拉拔等工序得到超导线材。铌板在加工过程中经过多道次变形、多次退火,最终以超导线材阻隔层的形式存在。因此,对超导线材用铌板的晶粒度、力学性能及均匀性等方面提出较高要求。对铌板的轧制工艺、热处理制度设计了对照试验并进行了深入研究。通过对比成品板材的晶粒度、力学性能差异,分析并得到了最优方案。开坯锻造、热轧、中间轧制以及成品轧制温度分别为1300℃、1050℃、960℃以及860℃工艺下,所生产的超导用铌板晶粒度为≥5.0级(以6.0~7.0级为佳)、再结晶率≥95%、Rp0.2≥72MPa,其再结晶率与屈服强度合格率较高,晶粒度分布均匀且评级合格。在稳定生产工艺与产品质量的基础上,对比总结的铌板轧制工艺对提高产品质量、积累超导铌材加工经验具有重要意义。
Niobium is an important barrier layer material for superconducting wires.Niobium plates are welded by rolls and loaded with superconducting core materials such as Nb3Sn and NbTi,and then superconducting wires are obtained through extrusion,cluster drawing and other processes.Niobium plate is deformed and annealed in multiple fires during processing,and finally exists in the form of a superconducting wire barrier layer.Therefore,the niobium plate for superconducting wires has high requirements on grain size,mechanical properties and uniformity.In this paper,the rolling process and heat treatment system of niobium plate were designed and thoroughly studied in a controlled test.By comparing the differences in grain size and mechanical properties of the finished plates,the results were analyzed and the optimal solution was obtained.Niobium plates for superconducting use were produced at the temperatures of 1300℃,1050℃,960℃and 860℃for forging,hot rolling,intermediate rolling and finished rolling,respectively.The Nb plates produced at these temperatures have a grain size of≥5.0(preferably 6.0~7.0),a recrystallization rate of≥95%,and a Rp0.2 of≥72MPa.The recrystallization rate and yield strength pass rate are high,the grain size distribution is uniform and the rating is consistent.On the basis of stable production process and product quality,the rolling process of niobium plate summarized in this paper is of great significance for improving product quality and accumulating superconducting niobium processing experience.
作者
刘倚天
胡淑娟
王飞
郝小雷
李浩
LIU Yitian;HU Shujuan;WANG Fei;HAO Xiaolei;LI Hao(Xi'an Noble Rare Metal Materials Co.,Ltd.,Xi'an 710201,Shaanxi,China)
关键词
超导铌板
轧制
热处理
晶粒度
力学性能
superconducting niobium plate
rolling
heat treatment
grain size
mechanical properties
