Study on the Fracture Mode of Nb 3 Sn Wire

Nb3Sn wire is a low-temperature superconducting material with tremendous development potential due to its high critical magnetic field and current carrying density. It has been extensively used in a variety of applications, including huge particle accelerators, superconducting energy storage systems, and magnetic confinement nuclear fusion devices. The internal-tin Nb3Sn wire is made of copper, niobium, tantalum, and tin. Its structure is more complex than that of NbTi wire, making it difficult to determine the exact cause of fracture. This intricacy significantly impedes the study and production of Nb3Sn wire. In this work, a high-resolution X-ray tomography equipment was used to scan and recreate the Nb3Sn fracture. Then we analyzed the sample after atepwise polishing using a scaning eletron microscope (SEM) to verify the aforementioned results. We study the various fracture modes of the wire and discover the causes of the fractures. We present a fracture analysis approach for determining the source of cracks. The fracture can be split into three parts: the fracture source region, the fracture expansion region, and the ultimate fracture region. The genesis of the fracture source and expansion model were investigated using microstructure data.