添加Be对CoCrFeNi高熵合金组织和性能影响的研究

目的 研究CoCrFeNi高熵合金组织和性能在添加Be后的变化，通过高熵合金固溶体相形成规律，设计从面心立方固溶体转变至含体心立方及金属间化合物的(CoCrFeNi)1-xBex系列高熵合金。方法 通过计算验证(CoCrFeNi)1-xBex系列高熵合金的成分是否落入固溶体区域，并对上述成分高熵合金组织和力学性能进行研究。结果 Be元素的原子数分数为4%时，高熵合金仍为单一的FCC相结构，随着Be元素含量的进一步增加，基体中出现BCC相和金属间化合物。Be的添加使得(CoCrFeNi)1-xBex高熵合金的屈服强度及显微硬度均大大提高，同时密度降低。结论 根据相形成规律设计的(CoCrFeNi)1-xBex系列高熵合金表明，适量添加Be元素可以改善CoCrFeNi高熵合金的综合物理力学性能。

Effect of Adding Be on Microstructure and Properties of CoCrFeNi High Entropy Alloy

The work aims to study the microstructure and properties of CoCrFeNi high entropy alloys (HEA) with Be addition. The (CoCrFeNi)1-xBex series of high entropy alloys were designed to transform from face-centered cubic solid solution to body-centered cubic and intermetallic compounds based on the formation law of high entropy alloy solid solution phase. The components of the (CoCrFeNi)1-xBex series high entropy alloys were calculated to verify whether they fell into the solid solution region, and the microstructure and mechanical properties of (CoCrFeNi)1-xBex series high entropy alloys were studied. When the content of Be was 4at.%, the HEAs had a single FCC phase structure. With the increase of Be content, BCC phase and intermetallic compounds appeared in the matrix. The yield strength and microhardness of (CoCrFeNi)1-xBex HEAs were increased and the density was decreased with the addition of Be. In summary, the addition of Be improved the comprehensive mechanical properties of CoCrFeNi HEA.