Effect of carbon and oxygen on microstructure and mechanical properties of Ti-25V-15Cr-2Al (wt%) alloys

被引:90
作者
Li, YG [1 ]
Blenkinsop, PA
Loretto, MH
Rugg, D
Voice, W
机构
[1] Univ Birmingham, IRC Mat High Performance Applicat, Birmingham B15 2TT, W Midlands, England
[2] Rolls Royce PLC, Derby DE24 8BJ, England
基金
英国工程与自然科学研究理事会;
关键词
titanium alloys; carbides; microstructure; mechanical properties; oxygen embrittlement;
D O I
10.1016/S1359-6454(99)00173-1
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
The effect of carbon additions on microstructure and mechanical properties of alloys with different levels of oxygen was studied in beta titanium alloys of the general composition Ti-25V-15Cr-2Al (all compositions are in wt% unless otherwise indicated). The microstructures were studied using optical microscopy (OM), X-ray diffractometry (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was found that titanium carbides with vacancy-ordered structure formed in all alloys with C additions of over 1000 w.p.p.m. Grains were refined by carbides. Wavelength-dispersive X-ray (WDX) analysis showed that oxygen was much higher in carbides than in beta matrix. After long-term exposure at 550 degrees C alpha precipitation was significantly reduced in samples with titanium carbides compared with those without. A significant improvement in room temperature tensile ductility was achieved by the addition of carbon to the alloys. Elongations of similar to 10% were obtained in samples which were exposed at 550 degrees C for 500 h following heat treatments at 1050 and 700 degrees C. (C) 1999 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved.
引用
收藏
页码:2889 / 2905
页数:17
相关论文
共 14 条
[1]   ORDERED DISTRIBUTION OF CARBON ATOMS IN TITANIUM CARBIDE [J].
BELL, PS ;
LEWIS, MH .
PHILOSOPHICAL MAGAZINE, 1971, 24 (191) :1247-&
[2]   AN EXAMINATION OF PART OF THE TITANIUM CARBON SYSTEM [J].
BICKERDIKE, RL ;
HUGHES, G .
JOURNAL OF THE LESS-COMMON METALS, 1959, 1 (01) :42-49
[3]  
BRODERICK TF, 1996, TITANIUM 95 SCI TECH, P2385
[4]  
GLAZUNOV SG, 1965, PHASE DIAGRAM TITANI, P289
[5]   NEUTRON DIFFRACTION STUDIES ON TITANIUM-CARBON AND ZIRCONIUM-CARBON ALLOYS [J].
GORETZKI, H .
PHYSICA STATUS SOLIDI, 1967, 20 (02) :K141-&
[6]  
Khaenko B. V., 1980, Soviet Physics - Crystallography, V25, P63
[7]  
Li YG, 1998, MATER SCI TECH SER, V14, P732, DOI 10.1179/026708398790300927
[8]   Structure and stability of precipitates in 500°C exposed Ti-25V-15Cr-xAl alloys [J].
Li, YG ;
Blenkinsop, PA ;
Loretto, MH ;
Walker, NA .
ACTA MATERIALIA, 1998, 46 (16) :5777-5794
[9]  
LI YG, 1996, TITANIUM 95 SCI TECH, P2317
[10]  
LI YW, 1997, UNPUB