碳微合金化对Ti-4.5Al-3.5Zr-2Fe低成本钛合金组织及力学性能的影响

Effects of carbon microalloying on microstructure and mechanical properties of low-cost Ti-4.5Al-3.5Zr-2Fe titanium alloy

采用水冷铜坩埚真空感应悬浮熔炼炉制备了不同碳含量为0、0.1%、0.15%和0.3%的Ti-4.5Al-3.5Zr-2Fe低成本钛合金,研究了碳微合金化对钛合金铸态组织和力学性能的影响。结果表明:随着碳元素的引入,原始β晶粒以及α片层宽度尺寸有一定的细化,合金铸态凝固组织由魏氏组织逐渐转变为网篮组织,TiC在晶界析出。碳含量增加,合金强度增强,塑性降低,其中Ti-4.5Al-3.5Zr-2Fe-0.1C合金综合力学性能最佳,抗拉强度和屈服强度分别为979 MPa和920 MPa,延伸率为5.4%。

Low-cost Ti-4.5Al-3.5Zr-2Fe titanium alloys with different carbon content of 0,0.1%,0.15%and 0.3%were prepared in a water-cooled copper crucible vacuum induction levitation melting furnace.The effects of carbon microalloying on the as-cast microstructure and mechanical properties of the titanium alloys were investigated.The results show that with the introduction of carbon element,the originalβgrain andαlamellar width are refined to a certain extent,and the as-cast solidification microstructure of the alloy is gradually transformed from Widmanst?tten microstructure to basket-weave microstructure,and TiC precipitates at grain boundary.Ti-4.5Al-3.5Zr-2Fe-0.1C alloy has the best comprehensive mechanical properties,with a tensile strength and yield strength of 979 MPa and 920 MPa,respectively,and an elongation of 5.4%.