摘要
通过非自耗真空电弧熔炼炉熔炼了不同Al元素含量的Ti_(92-x)Al_(x)Cr_(3)Nb_(5)(x=30、32、33,w/%)合金,并采用金相显微镜、扫描电子显微镜和电子万能试验机等研究了Al元素含量对TiAl合金微观组织和力学性能的影响。研究发现:Ti_(92-x)Al_(x)Cr_(3)Nb_(5)合金显微组织主要由α_(2)相和γ相组成,随着Al元素含量的增加,α_(2)相的形成受到抑制,含量减少,γ相含量增加;拉伸变形后的TiAl合金晶粒发生细化,硬度显著增大;TiAl合金在室温拉伸下主要为脆性断裂,并且抗拉强度和屈服强度随着Al元素含量的增加而增大,当Al元素含量增加到32%时断后伸长率较优;过量的Al元素驱动Nb元素在晶界偏聚,导致B2相有序化,形成硬脆相。
The Ti_(92-x)Al_(x)Cr_(3)Nb_(5)(x=30,32,33,mass fraction,%)alloys with different Al element contents were melted in a non-consumable vacuum arc melting furnace.The influence of Al element content on the microstructure and mechanical properties of the TiAl alloy was investigated by using metallographic microscope,scanning electron microscope and electronic universal testing machine,etc.The research shows that the microstructure of Ti_(92-x)Al_(x)Cr_(3)Nb_(5)alloy mainly consists ofα_(2)phase andγphase.With the increase of Al element content,the formation ofα_(2)phase is inhibited,and the content decreases,but the content ofγphase increases.After tensile deformation,the grains of the TiAl alloy are refined,the hardness increases significantly.TiAl alloys are mainly brittle materials under tensile conditions at room temperature.The tensile strength and yield strength increase with the increase of Al element content,and the elongation after fracture is better when the Al element content reaches 32%.Excessive Al element drives the segregation of Nb element in grain boundaries,resulting at B2 ordering and forming brittle and hard phases.
作者
邓文浩
龚勋
赵晖
金钧
张杰
王迪
Deng Wenhao;Gong Xun;Zhao Hui;Jin Jun;Zhang Jie;Wang Di(School of Materials Science and Engineering,Shenyang University of Technology,Shenyang 110159,China)
出处
《钛工业进展》
2025年第6期12-16,共5页
Titanium Industry Progress
基金
国家自然科学基金资助项目(U24A2037)。
