【摘要】 利用场发射扫描电镜(FE-SEM),X射线衍射仪(XRD),差热分析仪(DSC)等测试手段和分析方法,比较系统地研究了TB8钛合金的双级时效过程中组织演变及强化响应行为。结果表明:TB8钛合金在400℃/1 h预时效时β基体析出ω相,而在随后进行的500℃终级时效时ω相转变为α相。随着终级时效的持续,合金的硬度明显提高,合金析出α相的数量不断增加,尤其(101)α的衍射峰强度明显增强。经FE-SEM、DSC和XRD的结果分析发现,预时效处理产生了较多的细小弥散析出相,成为α沉淀相的转变基础,终级时效在5.5 h时基本完成相转变,而双级时效有利于减小析出α相的尺寸。更多还原

【Abstract】 Microstructure evolution and hardening response behavior during duplex aging of TB8 titanium alloy were investigated by field emission scanning electron microscopy( FE-SEM),X-ray diffraction( XRD),differential scanning calorimeter( DSC). Results show thatω precipitates appeared when the alloy is treated by pre-aging at 400 ℃ for 1 h,and these precipitates transform from ω to α phase in the subsequent final-aging process at 500 ℃. Hardness of the samples increases obviously in the process of final-aging treatment,and enhanced intensity of( 101) α peak suggested amount of α phase increases synchronistically. Results of FE-SEM,DSC and XRD analysis find that pre-aging treatment generated lots of ω precipitates,which supplied the basis of precipitating of fine α phase,and the transformation completion nearly needed about 5. 5 h final-aging treatment at 500 ℃.更多还原