Texture studies of hot compressed near alpha titanium alloy (IMI 834) at 1000°C with different strain rates

17th International Conference on Textures of Materials

材料科学;物理学

Kodli, B.K.^1 ; Saxena, K.K.^2 ; Dey, S.R.^1 ; Pancholi, V.^2 ; Bhattacharjee, A.^3

Department of Materials Science and Metallurgical Engineering, Indian Institute of Technology Hyderabad, Yeddumailaram-, Telangana

502205, India^1

Department of Metallurgical and Materials Engineering, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand

247667, India^2

Titanium Alloy Group, Defence Metallurgical Research Laboratory (DMRL), Kanchanbagh, Telangana

500058, India^3

关键词: Bi-modal microstructures;    Deformation behavior;    Electron back-scattered diffraction;    High temperature;    IMI-834 titanium alloy;    Low pressure compressor;    Near alpha titanium alloys;    Service temperature;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/82/1/012032/pdf
DOI  :  10.1088/1757-899X/82/1/012032

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

IMI 834 Titanium alloy is a near alpha (hcp) titanium alloy used for high temperature applications with the service temperature up to 600°C. Generally, this alloy is widely used in gas turbine engine applications such as low pressure compressor discs. For these applications, good fatigue and creep properties are required, which have been noticed better in a bimodal microstructure, containing 15-20% volume fraction of primary alpha grains (αp) and remaining bcc beta (β) grains transformed secondary alpha laths (αs). The bimodal microstructure is achieved during processing of IMI 834 in the high temperature α+β region. The major issue of bimodal IMI 834 during utilization is its poor dwell fatigue life time caused by textured macrozones. Textured macrozone is the spatial accumulation of similar oriented grains in the microstructure generated during hot processing in the high temperature α+β region. Textured macrozone can be mitigated by controlling the hot deformation with certain strain rate under stable plastic conditions having β grains undergoing dynamic recrystallization. Hence, a comprehensive study is required to understand the deformation behavior of α and β grains at different strain rates in that region. Hot compression tests up to 5°% strain of the samples are performed with five different strain rates i.e. 10-3s-1, 10-2s-1, 10-1s-1, 1 s-1and 10 s-1at 1000°C using Gleeble 3800. The resultant bimodal microstructure and the texture studies of primary alpha grains (αp) and secondary alpha laths (αs) are carried out using scanning electron microscopy (SEM)-electron back scattered diffraction (EBSD) method.