超高强Ti-15Mo-2.7Nb-3Al-0.2Si钛合金的强化行为及模型
Strengthening behavior and model of ultra-high strength Ti-15Mo-2.7Nb-3Al-0.2Si titanium alloy
石晓辉 1张琪 1荆镇 1范智渊 1刘江林 2乔珺威1
作者信息
- 1. 太原理工大学材料科学与工程学院,太原 030024
- 2. 太原理工大学机械与运载工程学院,太原 030024
- 折叠
摘要
基于XRD、OM、SEM和TEM分析,研究超高强Ti-15Mo-2.7Nb-3Al-0.2Si钛合金的组织演变及强化行为.结果表明,位错强化和析出强化效应对该合金的屈服强度影响较大.冷轧+再结晶+冷轧+双时效组合工艺可获得1518 MPa的最高屈服强度,这主要归因于显微组织中的高密度残存位错及密集而细小的次生α相.建立复合强化模型,其预测误差在16.6％以内.此外,研究发现次生α相体积分数的增加可以不断强化晶内区域,这使得沿晶断裂开始出现并逐渐占据整个断裂面.
Abstract
The microstructure evolution and strengthening behavior of the ultra-high strength Ti-15Mo-2.7Nb-3Al-0.2Si titanium alloy were studied utilizing XRD,OM,SEM,and TEM analyses.The results show that the dislocation-strengthening and precipitation-strengthening effects could mostly affect the yield strength of this alloy.The highest yield strength of 1518 MPa was obtained under a combined process of cold rolling+recrystallization+cold rolling+duplex aging.This trend is mainly due to the high density of remaining dislocations,as well as dense and thin secondary α phases in microstructures.A theoretical composite-strengthening model was built,and the prediction error is within 16.6％.Furthermore,it is found that increasing the content of the secondary α phase can continuously strengthen the intragrain zone.This feature causes the intergranular fracture to appear and gradually dominate the fracture surface.
关键词
强化模型/超高强/强化行为/钛合金/Ti-15Mo-2.7Nb-3Al-0.2SiKey words
strengthening model/ultra-high strength/strengthening behavior/titanium alloy/Ti-15Mo-2.7Nb-3Al-0.2Si引用本文复制引用
基金项目
Fundamental Research Program of Shanxi Province(202203021211130)
国家自然科学基金(51801132)
国家自然科学基金(52075359)
出版年
2024
NETL
NSTL
维普
万方数据