Influence of semisolid forging ratio on the microstructure and mechanical properties of Ti14 alloy  

作　　者：Yong-nan Chen Gang Liu Xue-min Zhang Yong-qing Zhao 

机构地区：[1]State Key Laboratory for Mechanical Behavior of Material, Xi'an Jiaotong University [2]School of Materials Science and Engineering, Chang'an University [3]Northwest Institute for Nonferrous Metal Research

出　　处：《International Journal of Minerals,Metallurgy and Materials》2013年第3期266-272,共7页矿物冶金与材料学报（英文版）

基　　金：financially supported by the Major State Basic Research Development Program of China (No.2007CB613807);the State Key Laboratory for Mechanical Behavior of Materials (No. 0111201);the National Natural Science Foundation of China (No. 51201019)

摘　　要：The present work is focused on the microstructure and mechanical properties of Ti14 alloy with different semisolid deformation ratios during forging tests. The results revealed that the forging ratio had a significant effect on the precipitation of the alloy. Fewer plate-shaped Ti2Cu tended to precipitate on grain boundaries with higher forging ratios, and finally the plate-shaped Ti2Cu formed precipitate-free zones along grain boundaries with a forging ratio of 75%. The precipitation on grain boundaries was found to be controlled by a peritectic reaction. Large forging ratios accelerated the extrusion of liquid and resulted in less liquid along the prior grain boundaries, which reduced the peritectic precipitation in this region and formed precipitate-free zones during re-solidification. In addition, increasing the forging ratio could accelerate dynamic recrystallization, which is favorable for improving the semisolid formability. The tensile ductility increased with increasing forging ratio, and a mixed fracture mode, involving both cleavage and dimple fracture, was observed after forging with a forging ratio of 75%, which along grain boundaries during semisolid processing. is attributed to the presence of precipitate-free zones formedThe present work is focused on the microstructure and mechanical properties of Ti14 alloy with different semisolid deformation ratios during forging tests. The results revealed that the forging ratio had a significant effect on the precipitation of the alloy. Fewer plate-shaped Ti2Cu tended to precipitate on grain boundaries with higher forging ratios, and finally the plate-shaped Ti2Cu formed precipitate-free zones along grain boundaries with a forging ratio of 75%. The precipitation on grain boundaries was found to be controlled by a peritectic reaction. Large forging ratios accelerated the extrusion of liquid and resulted in less liquid along the prior grain boundaries, which reduced the peritectic precipitation in this region and formed precipitate-free zones during re-solidification. In addition, increasing the forging ratio could accelerate dynamic recrystallization, which is favorable for improving the semisolid formability. The tensile ductility increased with increasing forging ratio, and a mixed fracture mode, involving both cleavage and dimple fracture, was observed after forging with a forging ratio of 75%, which along grain boundaries during semisolid processing. is attributed to the presence of precipitate-free zones formed

关 键 词：titanium alloys SEMISOLID FORGING microstructure PRECIPITATES mechanical properties 

分 类 号：TG319[金属学及工艺—金属压力加工]