Measurements of γ/γ＇ Lattice Misfit and γ＇ Volume Fraction for a Ru-containing Nickel-based Single Crystal Superalloy

• 来源期刊: 材料科学技术学报：英文版
• 学科: 工学
• 关键词: 镍基单晶高温合金 体积分数 晶格失配 测量 X射线衍射仪 实验过程 拟合模型 单晶硅材料
• 年，卷（期）: 2011,（10）
• 页码范围: 899-905
• 页数: 7页
• 分类号: TG146.15|TB333
• 语种: 英文

摘要

A conventional X-ray difFractometer has been used to determine the -y/y＇ lattice misfit and γ＇ volume fraction for a Ru-containing nickel-based single crystal superalloy at room temperature. The rocking curve was used to characterize the distribution of subgrains. The diffraction peaks obtained by w-20 scan were used to determine the γ/γ＇ lattice misfit and γ＇ volume fraction. A three peaks fitting model was proposed. The peak fitting results are in good agreement with the model. The X-ray diffraction results indicate that the nickel-based single crystal superalloy was not a perfect monocrystalline material, which is comprised of many subgrains; and each subgrain also consists of large numbers of mosaic structures. In addition, two anomalous reflection phenomena were found during the experiment and discussed with respect to their occurrence and impact on the measurement. The experimental results show that the γ/γ＇ lattice misfit and ~/r volume fraction will be various at the different regions of its dendritic microstructure. The average γ/γ＇ lattice misfit and γ＇ volume fraction of the experimental alloy are approximately-0.2% and 70%, respectively. Furthermore, the γ＇ volume fraction calculated by atom microprobe （AP） data is also basically consistent with the experimental results.