NbTi合金的主要缺陷及形成机制

Main Defects of NbTi Alloy and the Formation Mechanism

摘要:

通过对NbTi超导线材的制备过程中引起断线的典型缺陷表征，分析了NbTi合金中加工流线的形成和溶质再分配导致的富Ti偏析现象以及流线和暗斑的形成机理。结果表明：NbTi合金中的富Ti偏析可用X-Ray透射照片中的呈现的黑斑和木纹表征，其实质是一种通道偏析，为后续改进NbTi合金制备工艺，消除富Ti偏析、提高NbTi合金成分以及组织均匀性奠定基础

Abstract:

The typical defects resulting in the broken wire during the preparation of NbTi superconducting alloy wires was described. The formation mechanism of forging streamline, the Ti-riched segregation resulted from solute redistribution and the mechanism of streamline and black spots were analyzed. The results indicate that the Ti-riched segregation of NbTi alloy could be described by black spots and tree ring in X-ray photograph and the essence of this segregation is channel segregation. It is aimed to provide a method to optimize the preparation technology, which can eliminate the Ti-rich segregation and improve the constituent and microstructure homogeneity of NbTi superconducting alloy.