Refractory high entropy alloys (RHEAs), as a novel class of multi-principal element alloys, have attracted significant attention owing to their excellent properties. However, their low plasticity limits their potential applications, while the high melting points of the alloying elements face challenges to additive manufacturing (AM). Herein, RHEA, with extensively distributed cellular structure within their grains, was successfully fabricated using AM. Furthermore, we proposed a simple strategy to form a complete dislocation network within the cellular structure region in advance through cyclic deformation processing in the elastic stage (microplastic deformation). Dislocation networks are entangled with other dislocations, creating numerous pinned points adjacent cell walls, which impede dislocation motion. As a result, the cyclic deformation processing of RHEA achieves a yield strength of 1136 MPa while maintaining 50 % deformation strain without fracturing. The cyclic deformation processing method provides a route to strengthen additively manufactured alloys, offering a solution to overcome the trade-off between strength and plasticity.

中文翻译：

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通过增材制造耐火材料高熵合金的预组装位错网络提高强度和塑性


难熔高熵合金 （RHEAs） 作为一类新型的多主元素合金，因其优异的性能而受到广泛关注。然而，它们的低可塑性限制了它们的潜在应用，而合金元素的高熔点则面临着增材制造 （AM） 的挑战。在此，使用 AM 成功制备了在其晶粒内具有广泛分布的细胞结构的 RHEA。此外，我们提出了一种简单的策略，通过在弹性阶段的循环变形处理（微塑性变形）提前在细胞结构区域内形成完整的位错网络。位错网络与其他位错纠缠在一起，在细胞壁附近创建许多固定点，从而阻碍位错运动。因此，RHEA 的循环变形加工实现了 1136 MPa 的屈服强度，同时保持了 50% 的变形应变而不会断裂。循环变形加工方法提供了一种强化增材制造合金的途径，为克服强度和塑性之间的权衡提供了一种解决方案。