Microstructure and low cycle fatigue of a Ti2AlNb-based lightweight alloy  

作　　者：Yinling Zhang Aihan Feng Shoujiang Qu Jun Shen Daolun Chen 

机构地区：[1]School of Materials Science and Engineering,Tongji University,Shanghai 201804,China [2]Department of Mechanical and Industrial Engineering,Ryerson University,Toronto,Ontario M5B 2K3,Canada [3]Shanghai Key Laboratory of D&A for Metal-Functional Materials,School of Materials Science&Engineering,Tongji University,Shanghai 201804,China [4]College of Mechatronics and Control Engineering,Shenzhen University,Shenzhen 518060,China

出　　处：《Journal of Materials Science & Technology》2020年第9期140-147,共8页材料科学技术（英文版）

基　　金：supported by the National Natural Science Foundation of China (NSFC)(Grant No. 51871168);the Natural Sciences and Engineering Research Council of Canada (NSERC) in the form of international research collaboration;China Scholarships Council (CSC) for providing a PhD student scholarship;the financial support by the Premier’s Research Excellence Award (PREA);NSERC-Discovery Accelerator Supplement (DAS) Award;Canada Foundation for Innovation (CFI);Ryerson Research Chair (RRC) program

摘　　要：Ti2AlNb-based intermetallic compounds are considered as a new category of promising lightweight aerospace materials due to their balanced mechanical properties.The aim of this study was to evaluate monotonic and cyclic deformation behavior of an as-cast Ti-22A1-20Nb-2V-1Mo-0.25Si(at.%)intermetallic compound in relation to its microstructure.The alloy containing an abundant fine lamellar O-Ti2AlNb phase exhibited a good combination of strength and plasticity,and superb fatigue resistance in comparison with other intermetallic compounds.Cyclic stabilization largely remained except slight cyclic hardening occurring at higher strain amplitudes.While fatigue life could be described using the common Coffin-Mason-Basquin equation,it could be better predicted via a weighted energy-based approach.Fatigue crack growth was characterized mainly by crystallographic cracking,along with fatigue striationlike features being unique to appear in the intermetallics.The results obtained in this study lay the foundation for the safe and durable applications of Ti2AlNb-based lightweight intermetallic compounds.

关 键 词：Ti2AlNb-based alloy Cyclic deformation Low cycle fatigue Fatigue life prediction FRACTURE 

分 类 号：V252[一般工业技术—材料科学与工程] TG146.23[航空宇航科学与技术—航空宇航制造工程]