Fujieda的和Shiratori的研究发现,除了B2/BCC相外,EBMed AlCoCrFeNi样品中还产生了FCC相,而铸态样品甚至原料粉末中都没有发现FCC相。形成FCC相的原因是FCC相在EBM的预热温度(950°C)下热力学稳定。在微观和纳米尺度上分析了元素的波动。在铸造和EBMed样品的晶界处都可以观察到Fe和Cr的偏析,如图5b所示。此外,在EBM...
随机互溶的固溶体是高熵合金典型的组织,包括FCC、BCC以及HCP结构。此外,非晶态相也会在合金中生成。 (4)已证实的性能特点: 研究表明,高熵合金具有众多优于传统合金的优能。目前,性能上的五大效应已被证实,其分别为低层错能、热稳定性、抗辐照、抗腐蚀以及易于克服性能上的“trade-off”效应。易金新材 AlCoC...
如果AlCoCrFeNi HEA合金以较低的冷却速率凝固,则在FCC基体内形成富铝BCC相。然而,由于陡峭的热梯度,没有足够的时间来发生这种扩散过程。如图12,一些BCC核沿着HCP带形成。这可以表明,BCC相在合金纳米结构中的成核优先位置在层错缺陷上。 激光功率和扫描速度对最终结构的影响如图13所示。如图13-(a)所示,E14中较高...
We introduce a novel transformation-induced plasticity mechanism, i.e., a martensitic transformation from fcc phase to bcc phase, in medium-entropy alloys (MEAs). A VCrFeCoNi MEA system is designed by thermodynamic calculations in consideration of phase stability between bcc and fcc phases. The ...
Films of Co, Ni, and Cu, which are normally fcc or hcp crystals at room temperature, were grown on single-crystal Fe(100) substrates to induce bcc ordering. Both Co and Ni grow as bcc(100) films on iron, but the Cu films are disordered. This is in contrast to epitaxy of Cu on ...
As such, besides giving theoretical support for the proposed mechanism, the calculations additionally underline the importance of the flexibility of the Triphos ligand as a κ2- or κ3-coordinated ligand: it can easily harbor a low-spin 3d8 Ni(II) halide species as a κ3-ligand, which is ...
#研究生日常#科研狗的日常#读博的日子#sci#研究生本文设计了一种新型亚稳双相Fe59Cr13Ni18Al10中熵合金,该合金的FCC和BCC相里均含有不同尺寸和形状的B2-NiAl强化相,多尺度异质结构使该合金在室温和液氮温度下的屈服强度分别约为1.2GPa和1.5GPa,并且均匀延伸率超过15%。 同时在室温和低温下具有优异强度和延展性...
Energetics of bcc-fcc lattice in Fe-Co-Ni compounds (abstract).Presents s of two studies. of study that applied the linear muffin tin orbital method to compute the energy properties of several ordered binary iron-nickel, iron-cobalt and ternary iron-nickel-cobalt compounds near the bcc-fcc ...
With increasing FCC structure and reducing BCC structure, the hardness of the HEA decreases. A lower hardness of HEAs with added Co may limit their application in an environment where hardness of the material and erosion-corrosion is required. However, an increase in Co concentration in HEAs ...
通过直接能量沉积(DED)制备的AlCoCrFeNi2.1共晶高熵合金(EHEA)表现出由FCC(L12)和BCC(B2)相组成的双相结构。 中南大学、金川镍钴研究设计院团队研究采用DED方法制备AlCoCrFeNi2.1 EHEA,并讨论了沉积高度对DED ed样品微观结构和力学性能的影响。此外,还阐明了微观结构与力学性能之间的关系。