碳微合金化对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 Titanium Alloy

作　　者：王志天 相志磊[1] 马小昭 韩竟俞 陈子勇[1] WANG Zhitian;XIANG Zhilei;MA Xiaozhao;HAN Jingyu;CHEN Ziyong(College of Materials Science and Engineering,Beijing University of Technology,Beijing 100020,China)

机构地区：[1]北京工业大学材料科学与工程学院,北京100020

出　　处：《热加工工艺》2023年第8期60-64,70,共6页Hot Working Technology

基　　金：国家自然科学基金项目(10009011201802);企事业单位委托科技项目(46009011201501)。

摘　　要：研究了碳含量对α+β型低成本钛合金Ti-4.5Al-3.5Zr-2Fe微观组织、室温力学性能的影响。结果表明:碳元素的引入细化了原始β晶粒,导致铸态凝固组织由魏氏转变为网篮组织。当碳添加量为0.1wt%~0.3wt%时,Ti C相由细小近等轴状变为短棒状和长条状。980℃热轧后,合金强度提升,塑性最高可达15%,力学性能明显改善。这是由于轧制过程中组织破碎晶内大量位错塞积,通过EBSD织构分析发现随着碳含量增加,织构强度减小,Ti C相为α相的再结晶提供了形核质点。其中Ti-4.5Al-3.5Zr-2Fe-0.1C合金在室温下表现出良好的强度和断裂伸长率匹配。The effects of carbon contents on the microstructure,room temperature mechanical properties of a α+β titanium alloy Ti-4.5Al-3.5Zr-2Fe were investigated.The results show that the addition of carbon lead to the refinement of originalβgrain and the transformation of the as-cast solidification microstructure from Widmanstatten to basketnet structure.When the amount of carbon increases from 0.1wt% to 0.3wt%,the TiC phase grows from small and nearly equiaxial to short rod and long strip.After hot rolling at 980℃,the strength of the alloy is increased,the plasticity is up to 15%,and the mechanical properties are obviously improved.This is due to the fact that the as-cast microstructure is broken during the rolling process,a large number of dislocation plugs accumulate in the grains,through EBSD texture analysis,it is found that as the carbon content increases,the strength of texture decreases,and TiC phase provides nucleation particles forαrecrystallization.Among them,Ti-4.5Al-3.5Zr-2Fe-0.1C alloy exhibit an excellent balance of strength and elongation to failure at room temperature.

关 键 词：低成本钛合金 微合金化 显微组织 力学性能 

分 类 号：TG111.7[金属学及工艺—物理冶金]