等通道转角挤压法制备超细晶纯钛的研究进展

近年来,围绕超细晶纯钛的制备及其性能提升方面开展了许多研究。本文综述了制备超细晶纯钛块材的等通道转角挤压工艺及其重要参数,分析了挤压过程中纯钛的位错滑移及孪晶变形机制。超细晶纯钛的强度、塑性、抗疲劳性能显著提高,而耐蚀性测试结果呈多样性,有待进一步研究。等通道转角挤压和后续热机械处理的结合,可进一步提高超细晶纯钛的综合性能,表明采用ECAP技术制备的超细晶纯钛在各行各业有着广阔的发展前景。

Research progress of ultrafine-grained pure titanium produced by equal-channel angular pressing

Recently, fabrication techniques of ultrafine-grained (UFG) pure titanium have been investigated to achieve enhanced performance. This paper reveals the process and properties of bulk ultrafine-grained pure titanium by equal-channel angular pressing (ECAP), with the influence of experimental parameters. Special attention is given to the deformation mechanisms via dislocation slip and twinning during ECAP. It is demonstrated that the change of microstructure in UFG Ti leads to significant enhancement of mechanical properties. Some mixed results about corrosion resistance of UFG Ti indicate the further investigations necessary. Special emphasis is placed on the combination of ECAP and other treatments for improving overall properties. It is shown that significant enhancement has been made in UFG commercial-purity Ti after ECAP plus thermal-mechanical treatment, suggesting promising prospects of ECAP process for titanium alloys in various industries.