论文标题
定量沉淀物分类和晶界超级合金中的晶界特性控制
Quantitative precipitate classification and grain boundary property control in Co/Ni-base superalloys
论文作者
论文摘要
采用了一种相关方法来评估一组新型的Co/Ni-base Superalloys中（碳化物和硼化物）沉淀的结构和化学。结构源自具有图案模板匹配的电子反向散射（EBSD），并使用能量分散X射线光谱（EDS）获得的化学反应。发现这些合金中的主要碳化物是Mo和W富含M6C结构的。 M2B硼化物也表现出MO，并且在大约0.085的B水平下观察到了M2B。这些阶段在没有EBSD提供的结构信息的情况下，仅在SEM中与SEM区分（EDS或反向散射Z-Contrast）都具有挑战性。仅相关化学和结构指纹识别是必要的，足以完全定义一个相。确定的阶段与使用Thermocalc预测的相位不同。我们还对这些合金中的晶界锯齿性进行了评估，并观察到仅在没有固定晶间沉淀物的情况下才能获得显着振幅。
A correlative approach is employed to simultaneously assess structure and chemistry of (carbide and boride) precipitates in a set of novel Co/Ni-base superalloys. Structure is derived from electron backscatter diffraction (EBSD) with pattern template matching, and chemistry obtained with energy dispersive X-ray spectroscopy (EDS). It is found that the principal carbide in these alloys is Mo and W rich with the M6C structure. An M2B boride, also exhibiting Mo and W segregation is observed at B levels above approximately 0.085 at.%. These phases are challenging to distinguish in an SEM with chemical information (EDS or backscatter Z-contrast) alone, without the structural information provided by EBSD. Only correlative chemical and structural fingerprinting is necessary and sufficient to fully define a phase. The identified phases are dissimilar to those predicted using ThermoCalc. We additionally perform an assessment of the grain boundary serratability in these alloys, and observe that significant amplitude is only obtained in the absence of pinning intergranular precipitates.
