Ultrafine-grained alloys fabricated by severe plastic deformation (SPD) have high strength but often poor uniform ductility. SPD via high-ratio differential speed rolling (HRDSR) followed by an annealing treatment was applied to Al_0.5CoCrFeMnNi to design the microstructure from which both high strength and high uniform strain can be achieved. The optimized microstructure was composed of an ultrafine-grained FCC matrix (1.7-2 µm) with a high fraction of high-angle grain boundaries (61%-66%) and ultrafine BCC particles (with a size of 0.6-1 µm and a volume fraction of 8%-9.3%) distributed uniformly along the grain boundaries of the FCC matrix. The precipitation of the hard and brittle σ phase was suppressed during annealing. In the severely plastically deformed microstructure, the nucleation kinetics of the BCC phase was accelerated, and continuous static recrystallization (CSRX) took place during the annealing process at 1273 K. Precipitation of the BCC phase particles occurring concurrently with CSRX effectively retarded the grain growth of the FCC grains during annealing. The sample with the optimized microstructure exhibited a high tensile strength of over 1 GPa with a good uniform elongation of 14%-20%. These tensile properties are comparable to those of transformation-induced plasticity steel. Strengthening mechanisms of the severely plastically deformed alloy before and after annealing were identified, and each strengthening mechanism contribution was estimated. The calculated result matched well with the experimental results.

通过严重的塑性变形（SPD）制成的超细晶粒合金具有高强度，但均匀延展性通常较差。通过高比率差速轧制（HRDSR）进行SPD，然后进行退火处理，对Al _0.5用CoCrFeMnNi设计可以实现高强度和高均匀应变的微观结构。优化的微观结构由高比例的高角度晶界（61％-66％）的超细FCC基质（1.7-2 µm）和尺寸为0.6-1 µm的BCC超细颗粒组成。体积分数为8％-9.3％）沿着FCC基质的晶界均匀分布。退火过程中抑制了硬而脆的σ相的析出。在严重塑性变形的微观结构中，BCC相的形核动力学得到加速，并且在1273 K的退火过程中发生了连续的静态重结晶（CSRX）。与CSRX同时出现的BCC相颗粒的沉淀有效地阻碍了CCC晶粒的生长。退火过程中的FCC晶粒。具有优化的微观结构的样品表现出超过1 GPa的高拉伸强度，良好的均匀伸长率为14％-20％。这些拉伸性能可与相变诱发塑性钢相媲美。确定了退火前后严重塑性变形合金的强化机理，并估算了每种强化机理的贡献。计算结果与实验结果吻合良好。并估算了每个加强机制的贡献。计算结果与实验结果吻合良好。并估算了每个加强机制的贡献。计算结果与实验结果吻合良好。