摘要
Ni_(3)Al金属间化合物的室温脆性问题极大地限制了其应用。通过“团簇加连接原子”模型对Ni_(3)Al金属间化合物进行成分和结构解析及成分设计,通过Co、Fe部分取代团簇壳层上的Ni,Ti部分取代连接原子Al,设计出六种合金。并对其显微组织及力学性能进行了表征。结果表明:六种合金的显微组织均由NiAl相(γ′相)、NiAl相(BCC)和少量共晶析出的第三相所构成,且通过TEM分析证实了基体为Ni_(3)Al相。相比于Ni_(3)Al金属间化合物,合金的室温强度、硬度和塑性均有大幅度的提升。分析其原因是由于基体为Ni_(3)Al相,保持了合金基体的强度和硬度,当Ni_(3)Al基体中析出少量的BCC相时,进一步提高合金的强度和硬度,而当BCC含量过高时,合金的强度和硬度降低,塑性升高。
The room temperature brittleness of Ni_(3)Al intermetallic compounds significantly limits its application. Accordingly, in this paper, the composition and structure of Ni_(3)Al intermetallic compounds are analyzed, and the composition is designed by the ’cluster plus connected atom’ model. Six alloys were designed by replacing some Ni on the cluster shell with Co and Fe and replacing some connecting atom Al with Ti. Simultaneously the microstructure and mechanical properties of these alloys were characterized. The results show that the microstructures of all six alloys are composed of the Ni_(3)Al phase(γ′ phase), Ni_(3)Al phase(BCC), and a small amount of eutectic precipitated third phase, and the formation of the Ni_(3)Al phase is confirmed by TEM analysis. The alloy designed in this paper has improved room temperature strength, hardness, and plasticity compared to the Ni_(3)Al intermetallic compound. The reason is that the formation of the Ni_(3)Al phase as the matrix improves the strength and hardness. When a small amount of BCC phase precipitates in the Ni_(3)Al matrix, it helps further to improve the strength and hardness of the alloy. In comparison, the high concentration of BCC decreased the strength and hardness and increased the plasticity.
作者
刘林
许雅南
田权伟
滕宗延
徐朝晖
王轶农
Liu Lin;Xu Yanan;Tian Quanwei;Teng Zongyan;Xu Zhaohui;Wang Yinong(School of Materials Science and Engineering,Dalian University of Technology,Dalian 116024,Liaoning,China)
出处
《钢铁钒钛》
CAS
北大核心
2022年第5期171-177,共7页
Iron Steel Vanadium Titanium
