Strength of Intermetallic Matrix Composites by Controlling Interface Reactions

通过控制界面反应提高金属间基复合材料的强度

• 批准号: 03452253
• 负责人: HANADA Shuji
• 金额: $ 4.8万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-03452253/
• 关键词: Intermetallic compound; composite; superplasticity; Isothermal forging; interface reaction; cohesive strength; low of mixtures; Ni_3Al; 複合則; 接合

Based on the obtained results in the proceding years, model composites of B doped Ni-rich Ni_3Al reinforced with W fibers are successfully fabricated by isothermal forging Ni_3Al plates sandwiching W fibers at 1373K to 1473K.It is found that isothermal forging of cold rolled Ni_3Al plates enables better consolidation and lower forging temperature than that of recystallized Ni_3Al plates. No reaction zone is formed at interfaces of as-fabricated composites. However, SEM/EDX result reveals that W and Ni diffuse each other, suggesting that strong bonding is produced at the interfaces.A stress-strain curve of the composite tensile tested at ambient temperature exhibits serrations resulting from brittle failure of W fibers. No pull-out of W fiber are observated in a fracture surface, indicating that cohesive strength between W fibers and matrix is very high.Deformation and fracture behavior of the composites at elevated temperatures are influenced by those of monolithic Ni_3Al alloys. Yield … More strength is higher in the composites than in the monotilluc alloys at all temperatures tested (ambient to 1323K). Especially, increase in strength by the reinforcement is remarkable (1.5 to 2 times) in the low (ambient to 973K) and high (above 1273K) temperature region. Strengthening is not attained in the intermediate temperature region (1073 to 1173K) because of brittle intergranular fracture in the matrix.Tensile strength in the low temperature region (e.g. 873K) is lower than that calculated by the low of mixtures, suggesting that B segregation to the W/Ni_3Al interfaces leads to decrease in B content at grain boundaries in the matrix. Tensile strength in the high temperature region (e.g. 1323K) is in fairly good agreement to the calculated value.It is revealed that W/Ni_3Al composites posses high strength over monolithic Ni_3Al alloys at temperatures up to 1323K.Holding above 1373K produces an interface place W_3Ni and Kirkendall voids, thereby reducing strength of the composites. Less

在前人研究的基础上，采用等温锻造的方法，在1373 ~ 1473 K温度范围内成功地制备了W纤维增强富Ni Ni_3Al/B复合材料。研究发现，与再结晶Ni_3Al板材相比，冷轧Ni_3Al板材的等温锻造具有更好的凝固性能和更低的锻造温度。复合材料的界面处没有反应区形成。SEM/EDX结果表明，复合材料中W和Ni相互扩散，界面结合较强;室温拉伸应力-应变曲线显示，W纤维的脆性破坏导致复合材料出现锯齿状断口。复合材料的高温变形和断裂行为与Ni_3Al合金的高温变形和断裂行为有很大的关系。产量 ...更多信息 在所有测试温度下（环境温度至1323 K），复合材料的强度高于单钛合金。特别是，在低温（环境温度至973 K）和高温（高于1273 K）区域中，增强体的强度增加是显著的（1.5至2倍）。在中温区（1073 ~ 1173 K），基体发生沿晶脆性断裂，不能获得强化，低温区（如873 K）的抗拉强度低于按混合料理论计算的抗拉强度，表明B向W/Ni_3Al界面偏聚，导致基体晶界处B含量降低。高温区（如1323 K）的拉伸强度与计算值吻合较好，表明W/Ni_3Al复合材料在1323 K以下具有比Ni_3Al合金高的强度，高于1373 K时，界面处产生W_3Ni和Kirkendall空洞，从而降低了复合材料的强度。少

项目成果

I.N.Jujur and S.Hanada: "Tensile properties of W/Ni_3Al Composites" Proc.Intern.Conf.

I.N.Jujur 和 S.Hanada：“W/Ni_3Al 复合材料的拉伸性能”Proc.Intern.Conf。

花田 修治: "Ni_3Alと高融点金属の接合" Materials Trans.,JIM.

Shuji Hanada：“Ni_3Al 与高熔点金属的连接”Materials Trans.，JIM。

I.N.Jujur and S.Hanada: "Tensile properties of W/Ni_3Al Composites at Elevated Temperatures" Proc.Intern.Conf.High-Temperature Intermetallics. (in press). (1994)

I.N.Jujur 和 S.Hanada：“W/Ni_3Al 复合材料在高温下的拉伸性能”Proc.Intern.Conf.高温金属间化合物。