( 1. 中南大学 材料科学与工程学院,长沙 410083;
2. School of Technology and Society, Malmö University,
Malmö 20506, Sweden)
摘 要: 采用真空电弧熔炼技术制备了4种成分的Ti-Sc二元合金, 并借助金相显微镜(OM)、 扫描电子显微镜(SEM)、 能谱分析(EDS)、 X射线衍射(XRD)技术及显微硬度测试, 对合金的组织形貌、 相成分以及不同形貌相的显微硬度进行了分析。 结果表明: 合金铸态组织形貌为螺旋状、 团簇状片层、 双相组织; 金属Sc对合金的组织有着明显的细化作用, 在合金中Sc与Ti形成了固溶体, 不同形貌的相, 其显微硬度差别较大; 当Sc含量为2%~3%时, Ti-Sc二元合金的显微硬度达到最高值, Sc含量高于2%~3%时, 合金基体硬度高于片层组织硬度, Sc含量低于2%~3%时, 合金基体硬度低于片层组织硬度, 少量Sc对合金性能有所提高, 对α相片层组织有强化作用。
关键字: Ti-Sc二元合金; 显微组织; 相结构; 显微硬度
( 1. School of Materials and Science Engineering,
Central South Universtity, Changsha 410083, China;
2. School of Technology and Society, Malmö University,
Malmö 20506, Sweden)
Abstract: Four kinds of Ti-Sc binary alloys were prepared by vaccum arc melting technique. Microstructure, phase components and microhardness of different phases were analyzed by optical microscopy(OM), scanning electron microscope(SEM), X-ray diffraction(XRD) and microhardness tester. The results show that scandium plays a significant role on refinement of the microstructure. Solid solution forms in Ti-Sc binary alloys. The measured microhardness of different phases are in significant discrepancy. Microhardness of Ti-Sc binary alloys reaches the maximum value with 2%-3% Sc. When Sc content is higher than 2%-3%, microhardness of matrix is higher than that of plate-like phases, contrary tendency can be seen when Sc content is lower than 2%-3%. Small content of scandium can improve the properties of alloys and strengthen the α plate-like phases.
Key words: Ti-Sc binary alloy; microstructure; phase structure; microhardness