Microstructure dependence of electrochemical corrosion resistance for rapidly solidified Ti_(50)Al_(48)Mo_(2)alloy  

作　　者：Chonghao Sun Ruilin Xiao Kelun Liu Ying Ruan Bingbo Wei 

机构地区：[1]MOE Key Laboratory of Materials Physics and Chemistry under Extraordinary Conditions,School of Physical Science and Technology,Northwestern

出　　处：《Journal of Materials Science & Technology》2024年第18期58-68,共11页材料科学技术（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.52225406,52073232,and 52088101);the National Key Research and Development Program of China(Nos.2021YFA0716301 and 2021YFB3700801);the Science Fund for Scientific and Technological Innovation Team of Shaanxi Province(No.2021TD-14).

摘　　要：The rapid solidification of undercooled liquid Ti_(50)Al_(48)Mo_(2)alloy was achieved by the electromagnetic lev-itation(EML)technique.At small and medium undercoolings,primary(βTi)dendrite reacted with sur-rounding liquid to drive a peritectic transformation into the(αTi)phase.The solutal Mo and Al segrega-tions were located within the dendrite center and the grain boundary during peritectic transformation,consequently B2 phase in the dendrite center andγphase at the grain boundary formed.Once under-cooling exceeded 253 K,the peritectic transformation was completely inhibited,and the formation of the B2 phase andγphase was completely suppressed.The ultrafine eutectoid structure was formed and a complete solute trapping effect was realized.Homogeneous solute distribution facilitated the forma-tion of thicker passivation film with lower defect density and higher film resistance on the alloy surface.Moreover,this weakened micro-galvanic effect reduced the susceptibility to pitting corrosion,and conse-quently the corrosion resistance of the alloy was improved.

关 键 词：Ti-Al based alloys Electromagnetic levitation technique UNDERCOOLING Rapid solidification Passivation film 

分 类 号：TG156.3[金属学及工艺—热处理] TG146.11[金属学及工艺—金属学]