The uniaxial tensile deformation behavior of a sandwich-like structural TiNb-NiTi composite was investigated by uniaxial tensile test and in situ high-energy synchrotron X-ray diffraction(SXRD).It is found that below ...The uniaxial tensile deformation behavior of a sandwich-like structural TiNb-NiTi composite was investigated by uniaxial tensile test and in situ high-energy synchrotron X-ray diffraction(SXRD).It is found that below 1.2%macroscopic strains,the elastic deformations of the B2,β,B19'andα"phases take place in the TiNbNiTi composite.During the subsequent loading,theβ→α"and B2→B19'stress-induced martensitic transformations(SIMTs)occur within the macroscopic strains of 0.5%-4.2%and the macroscopic strains of 0.7%-6.2%,respectively.At the macroscopic strain of about 4.2%,the outer TiNb layer of the TiNb-NiTi composite experiences a partial fracture,as proved by the disappearance of(040)_(α")and a sudden jump in the(110)_(B19')d-spacing caused by load transfer.With further uniaxial tensile deformation,the TiNbNiTi composite finally fractures at a strain of~6.2%.Our results might provide some valuable information for understanding the deformation behavior of novel sandwich-like structural shape memory composites in more depth.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.51771082 and51775251)the Six Talent Peaks Project in Jiangsu Province(No.2019-XCL-113)+1 种基金Zhenjiang Science&Technology Program(No.GY2020001)the Project of Faculty of Agricultural Equipment of Jiangsu University(No.NZXB20200101)。
文摘The uniaxial tensile deformation behavior of a sandwich-like structural TiNb-NiTi composite was investigated by uniaxial tensile test and in situ high-energy synchrotron X-ray diffraction(SXRD).It is found that below 1.2%macroscopic strains,the elastic deformations of the B2,β,B19'andα"phases take place in the TiNbNiTi composite.During the subsequent loading,theβ→α"and B2→B19'stress-induced martensitic transformations(SIMTs)occur within the macroscopic strains of 0.5%-4.2%and the macroscopic strains of 0.7%-6.2%,respectively.At the macroscopic strain of about 4.2%,the outer TiNb layer of the TiNb-NiTi composite experiences a partial fracture,as proved by the disappearance of(040)_(α")and a sudden jump in the(110)_(B19')d-spacing caused by load transfer.With further uniaxial tensile deformation,the TiNbNiTi composite finally fractures at a strain of~6.2%.Our results might provide some valuable information for understanding the deformation behavior of novel sandwich-like structural shape memory composites in more depth.