标题： 轻间隙原子（B、C、H和N）在Cr-Ni合金中的分离与排列：对超合金设计中晶界稳定性的影响 显示英文标题

标题： Segregation and Ordering of Light Interstitials (B, C, H, and N) in Cr-Ni Alloys: Implications for Grain Boundary Stability in Superalloy Design

摘要： 轻间隙元素（B、C和N）在Cr30-Ni中的偏析和有序行为被研究，因为这些元素对于镍基高温合金的晶界稳定性和高温力学性能至关重要。 使用蒙特卡罗模拟，我们确定了这些间隙元素在体相和晶界（GB）环境中的化学和结构偏好，与实验中的偏析和析出趋势一致。 硼强烈倾向于晶界而不是体相，在那里它增强了晶界结合力并稳定了晶界结构。 独特的是，硼在较高浓度下会引发结构转变，暗示在硼含量高的区域可能形成锯齿状晶界，这有助于提高高温力学性能。 碳和氮形成碳化物和氮化物模式，并表现出有限的晶界溶解度，强化了它们的析出倾向。 为了支持正在进行的氢脆缓解策略，我们还研究了氢的行为。 氢在Cr-Ni晶界区域表现出化学稳定性，表明它可能优先沿着铬和镍富集的晶界向内迁移，同时避开钼富集区域，进一步支持钼在缓解脆化中的作用。 这些发现表明，含钼的硼化物可能通过抑制氢的渗入和稳定晶界结合力，作为有效抵抗氢致退化的屏障。 通过阐明这些轻间隙元素的化学和结构偏好，这项工作提供了一个强大的计算框架，用于指导高温合金设计，以提高高温晶界稳定性、抗氢脆性和控制化学有序性。 显示英文摘要

摘要： The segregation and ordering behavior of light interstitials (B, C, and N) in Cr30-Ni is examined, as these elements are critical for grain boundary stability and high-temperature mechanical performance in Ni-based superalloys. Using Monte Carlo simulations, we identify the chemical and structural preferences of these interstitials in both bulk and grain boundary (GB) environments, aligning with experimental segregation and precipitation trends. Boron strongly prefers GBs over the bulk, where it enhances GB cohesion and stabilizes the GB structure. Uniquely, boron induces a structural transformation at higher concentrations, hinting at the formation of serrated GBs where boron content is high, which improves high-temperature mechanical performance. Carbon and nitrogen form carbide and nitride motifs and exhibit limited GB solubility, reinforcing their precipitation tendencies. In support of ongoing hydrogen embrittlement mitigation strategies, we also examined hydrogen behavior. Hydrogen demonstrated chemical stability in the Cr-Ni GB zone, suggesting it may preferentially migrate inward along Cr- and Ni-rich GBs while avoiding Mo-enriched regions, further supporting Mo's role in mitigating embrittlement. These findings suggest that Mo-containing borides may serve as effective barriers against hydrogen-induced degradation by inhibiting H ingress and stabilizing GB cohesion. By elucidating the chemical and structural preferences of these light interstitials, this work provides a robust computational framework for guiding superalloy design toward improved high-temperature grain boundary stability, resistance to hydrogen embrittlement, and controlled chemical ordering.