This paper give insight into the microstructural evolution during heat treatment and creep testing of a boron alloyed 9% Cr steel, with special emphasis on the role of boron, by using advanced analytical transmission electron microscopy methods. Electron energy loss spectrum images acquired in scanning transmission electron microscopy mode provide full elemental information in the form of compositionally quantified maps (atomsm3) of C, N, Fe, Cr, V and B with high spatial and energy resolution. MX precipitates embedded in the M23(C,B)6particle were identified and analysed with respect to their boron concentration. Energy filtered TEM elemental maps have been processed by applying bivariate histogram analysis in order to recognise an early stage transformation of vanadium nitride particles to the complex nitride named modified Z phase. Moreover, pre-austenite grain boundaries in the creep tested specimens have been charted and the phases were identified via energy filtering TEM, electron energy loss and X-ray spectrometry.%本文采用先进的扫描透射电子显微镜方法,研究含Cr为9％的硼合金化钢在热处理过程和蠕变测试过程中的微观组织的演变规律,并对于硼元素的作用进行了重点探讨.通过扫描透射电子显微镜获得的电子能量损失谱图像能提供具有高的空间和能量分辩率的碳、氮、铁、铬、钒的组成定量图(单位为atomsm3),这些图包含了丰富的元素信息.对包含在M23 (C,B)6颗粒中的MX析出相进行了鉴定,并分析了其中的硼含量.为了识别氮化钒颗粒向复杂的氮化物(改性Z相)的早期转变过程,通过应用二元直方图分析对能量过滤透射电子显微镜(TEM)的元素图谱进行处理.另外,该研究绘制了蠕变检测样品的原奥氏体晶界图,并通过能量过滤透射电子显微镜,电子能量损失和X射线光谱图对析出相进行了鉴别.
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