Grain Boundary and Interface Architecture for Ultra-High Temperature Materials -Occurrence of Super-Heat Resistance and Oxidation Resistance-

超高温材料的晶界和界面结构-抗过热性和抗氧化性的发生-

• 批准号: 10555226
• 负责人: WATANABE Tadao
• 金额: $ 7.23万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B).
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10555226/
• 关键词: ultra-high temperature material; intergranular oxidation; oxidation embrittlement; grain boundary character distribution (GBCD); grain boundary segregation; grain boundary engineering; EBSP; silicon carbide; 耐熱材料; 鉄基合金; 磁性; 非酸化物セラミックス; 粒界3重点 /

This project was conducted for development of heat- and oxidation-resistant materials at ultra-high temperatures through grain boundary and interface architecture. Main results obtained are as follows.1. A study on grain boundary oxidation and oxidation induced brittleness in Ni-Fe alloy : The effect of grain boundary structure on intergranular oxidation was investigated in a Ni-Fe alloy. We have found that intergranular oxidation preferentially takes place at random boundaries, while low-Σ coincidence boundaries such as Σ3, Σ11, Σ19 possess excellent oxidation resistance. Grain boundary engineering was applied to controlling oxidation induced embrittlement in polycrystalline Ni-Fe alloy by taking account of the grain boundary character distribution (GBCD) as well as the grain boundary density (grain size). The presence of an optimal grain boundary microstructure for this purpose has been predicted.2. Effect of grain boundary microstructure on mechanical property and grain boundary seg … More regation induced embrittlement in nanocrystalline nickel : We have found that the microhardness in nanocrystalline nickel decreases not only with increasing the frequency of coincidence boundaries but also with increasing triple points at which the coincidence boundaries are interconnected. In addition, we have confirmed that the grain boundary segregation induced brittleness can be improved by controlling the GBCD and the grain size.3. A study on Control of oxidation induced embrittlement in Silicon Carbides : The effect of dopants (Mg, Al, P) on the grain boundary microstructure was studied in β-silicon carbide. We have succeeded in changing the GBCD in β-silicon carbide by controlling dopants. In addition, we have evaluated oxidation induced embrittlement by 3-point bending test at room temperature using some specimens oxidized at different temperatures and oxygen partial pressures. It has been found that the oxidation embrittlement in β-silicon carbide can be effectively improved by decrease in the frequency of random boundaries and the grain size. Less

该项目旨在通过晶界和界面结构开发超高温下的耐热和抗氧化材料。主要研究结果如下：1. Ni-Fe合金晶界氧化及氧化脆性的研究：研究了Ni-Fe合金晶界结构对晶间氧化的影响。我们发现，晶间氧化优先发生在随机边界，而低重合度的边界，如103，1011，1019具有良好的抗氧化性。将晶界工程应用于多晶Ni-Fe合金的氧化脆化控制，从晶界特征分布（GBCD）和晶界密度（晶粒尺寸）两个方面考虑。预测了最佳晶界微结构的存在.晶界组织对力学性能及晶界偏析的影响 ...更多信息 纳米晶镍中的regation诱导脆化：我们已经发现，纳米晶镍中的显微硬度不仅随着重合边界频率的增加而降低，而且随着重合边界互连的三相点的增加而降低。此外，我们还证实了通过控制晶界偏聚和晶粒尺寸可以改善晶界偏聚引起的脆性.碳化硅氧化脆化控制的研究：研究了Mg、Al、P掺杂对β-SiC晶界微结构的影响。我们通过控制掺杂剂，成功地改变了β-碳化硅中的GBCD。此外，我们已经评估了氧化诱导脆化的三点弯曲试验在室温下使用一些试样在不同的温度和氧分压氧化。结果表明，降低随机晶界的出现频率和晶粒尺寸可以有效地改善β-SiC的氧化脆化。少

项目成果

K.Kaneko et al.: "Chemical bonding of oxgen in intergranular amorphous layers in high-purity β-SiC ceramics"Acta Materialia. 47. 1281-1287 (1999)

K. Kaneko 等人：“高纯 β-SiC 陶瓷中晶间非晶层中氧的化学键合”Acta Materialia。47. 1281-1287 (1999)

T.Watanabe: "Grain Boundary Engineering for High Performance Structural and Functional Materials"J.Phys. IV France. 10. Pr6-41-Pr6-46 (2000)

T.Watanabe：“高性能结构和功能材料的晶界工程”J.Phys。

S.Tsurekawa: "Grain Boundary Microstructure Dependent-Intergranular Fracture in Polycrystalline Molybdenum"MRS Conference Proceedings. 586(in press). (2000)

S.Tsurekawa：“多晶钼中晶界微观结构相关的晶间断裂”MRS 会议论文集。

K.Kawahara, S.Tsurekawa and H.Nakashima: "Dislocation Structure and Activated Slip Systems in β-Silicon Nitride during High Temperature Deformation"Key Eng. Mater.. 171-174. 825-832 (2000)

K.Kawahara、S.Tsurekawa 和 H.Nakashima：“高温变形过程中 β-氮化硅中的位错结构和激活的滑移系统”Key Eng. 171-174 (2000)。

K.Kaneko, M.Yoshiya, I.Tanaka and S.Tsurekawa: "Chemical Bonding of Oxygen in Intergranular Amorphous Layers in High-Purity β-SiC Ceramics"Acta Mater.. 47. 1281-1287 (1999)

K. Kaneko、M. Yoshiya、I. Tanaka 和 S. Tsurekawa：“高纯 β-SiC 陶瓷中晶间非晶层中氧的化学键合” Acta Mater.. 47. 1281-1287 (1999)