TA15钛合金β热变形行为及显微组织

发布时间：2018-02-11 03:06

本文关键词： TA钛合金 β热变形相变点动态再结晶显微组织定量分析　出处：《稀有金属》2015年11期 　论文类型：期刊论文

【摘要】：基于二元相图计算法和差示扫描量热法(DSC)精确测定了TA15钛合金的相变点。采用热模拟压缩实验、光学显微镜(OM)及电子背散射衍射技术(EBSD)和定量分析法研究了TA15钛合金的β热变形行为,分析了变形温度、应变速率和变形量对其流变应力和显微组织的影响规律。结果表明:TA15钛合金在β热变形时,流变应力曲线呈现两种软化态势:高应变速率条件下,流变应力曲线呈现动态再结晶型,而低应变速率条件下流变应力曲线呈现动态回复型;低应变速率下获得极细的片状马氏体微结构,而高应变速率下为粗大的板状马氏体微结构,且大角度晶界比例较低;应变速率对显微组织特征参数(β晶粒大小及不均匀性、β转变组织片层厚度以及长宽比)的影响较为显著。研究结果可为优化TA15钛合金β热变形工艺参数,获得良好的组织形态提供理论依据。
[Abstract]:Based on the binary phase diagram calculation method and differential scanning calorimetry (DSC), the phase transition points of TA15 titanium alloy were accurately determined. Optical microscope (OM), Electron Backscatter diffraction (EBSD) and quantitative analysis method were used to study the 尾 -thermal deformation behavior of TA15 titanium alloy, and the deformation temperature was analyzed. The effect of strain rate and deformation amount on the rheological stress and microstructure of titanium alloy is studied. The results show that the rheological stress curve of the alloy shows two kinds of softening tendency during 尾 -hot deformation: at high strain rate, the flow stress curve shows two kinds of softening tendency: under the condition of high strain rate, The rheological stress curve showed dynamic recrystallization, while at low strain rate the rheological stress curve showed dynamic recovery, and the microstructure of sheet martensite was obtained at low strain rate. At high strain rate, the microstructure of lath martensite is coarse, and the ratio of large angle grain boundary is low. The effect of strain rate on the characteristic parameters of microstructure (尾 grain size and inhomogeneity, thickness of 尾 transition microstructure and aspect ratio) is significant. The results can be used to optimize the 尾 hot deformation process parameters of TA15 titanium alloy. To obtain a good form of tissue to provide theoretical basis.
【作者单位】：合肥工业大学材料科学与工程学院;
【基金】：国家自然科学基金项目(51175137) 教育部新世纪优秀人才支持计划项目(NCET-13-0765)资助
【分类号】：TG146.23

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