The effect of cooling rates on the microstructure and mechanical properties of thermo-mechanically processed Ti-Al-Mo-V-Cr-Fe alloys

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:576

Article

Ahmed, Mansur¹  Savvakin, Dmytro G.²  Ivasishin, Orest M.²  Pereloma, Elena V.^1,3 

[1] Univ Wollongong, Sch Mech Mat & Mechatron Engn, Wollongong, NSW 2522, Australia

[2] Natl Acad Sci Ukraine, Inst Met Phys, UA-03142 Kiev, Ukraine

[3] Univ Wollongong, Elect Microscopy Ctr, Wollongong, NSW 2519, Australia

关键词: Ti alloys;    Cooling rate;    X-ray diffraction;    Microstructure;    Mechanical properties;   

DOI  :  10.1016/j.msea.2013.03.083

来源: Elsevier

【 摘 要 】

Two near-beta titanium alloys, Ti-5Al-5Mo-5V-1Cr-1Fe and a modified one containing 2 wt% Cr (Ti-5Al-5Mo-5V-2Cr-1Fe) were produced from Ti hydride precursor powders via the cost-effective blended elemental powder metallurgy technique. The effects of two cooling rates (10 K s(-1) and 1 K s(-1)) during thermo-mechanical processing on the microstructure and mechanical properties were investigated using X-ray diffraction and scanning electron microscopy. X-ray line profile analysis revealed that dislocation densities and microstrain in beta-Ti phase are higher than in alpha-Ti phase for all cases. In both alloys, slower cooling results in an increase in alpha volume fraction and promotes morphology of continuous grain boundary alpha phase. A lower total elongation is obtained in both alloys under slower cooling which could be accounted for by the continuous morphology of alpha phase. Overall, Ti-5Al-5Mo-5V-1Cr-1Fe displays higher ultimate tensile strength and total elongation compared to Ti-5Al-5Mo-5V-2Cr-1Fe, regardless of the cooling rate. (C) 2013 Elsevier B.V. All rights reserved.

【 授权许可】

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