【摘要】 研究了Ti-35V-15Cr(A)和Ti-25V-15Cr(B)两合金在不同温度、时间和拉应力条件下热暴露后的热稳定性能。结果表明,随着热暴露温度升高,合金性能恶化。600℃热暴露,B合金性能恶化的根本原因是表面氧化,A合金则是由于表面氧化与组织变化的共同作用。热暴露时间延长,合金塑性下降;热暴露拉应力增大,合金塑性有所提高;A合金540℃热稳定性较B合金差,两合金540℃热暴露塑性下降的主要原因来自于热暴露过程中微观组织的变化,其次为表面氧化。高钒含量A合金中的α相比低钒含量B合金中的α相更易聚集于晶界。晶界α相的析出和长大,是合金性能恶化并发生沿晶断裂的主要原因。更多还原

【Abstract】 The thermal stabilities of two Ti V Cr burn resistant titanium alloys, Ti 35V 15Cr(alloy A) and Ti 25V 15Cr(alloy B) were studied after exposure at different temperatures, tensile stress and time. The results show that post exposure tensile ductility deteriorates with increasing exposure temperature and time. When exposed at 600℃ , the reduction of thermal stability of alloy B with its high V content yesulted from severe surface oxidation, while that of low- V alloy A resulted from a combination of surface oxidation and microstructural changes. The post exposure tensile ductility improves with the increasing exposure tensile stress. Alloy B has better thermal stability at 540℃ than alloy A. The property reduction mainly comes from the microstructure evolution of the two alloys during their thermal exposure, and secondly from the surface oxidation. There is a tendency that more α phase agglomerates on boundaries in the high- V alloy A than in alloy B. Precipitation and growth of α phase in grain boundaries are the main reasons property deterioration and inter granular cracking.更多还原