Ultra-hard and wear-resistant metallic alloys are crucial for engineering applications to withstand prolonged wear and tear. However, fabricating multiple component alloys with varying hardness levels poses challenges in compositional design, processing optimization, and the application of hardening techniques across different alloy systems. Here, we demonstrate a facile approach for fabricating ultrahard FeMnAl(Cu) low-density medium entropy alloys (MEAs) with flexible hardness by inducing the precipitation of β-Mn via a routine aging process. This method enables a broad range of tunable hardness, from relatively soft (210 HV) to ultrahard (1042 HV), by controlling the precipitation of β-Mn in FeMnAl(Cu) low-density MEAs within a few hours of aging. The rapid aging-induced hardening response endowed these FeMnAl(Cu) MEAs with exceptional resistance to wear damage. These findings pave a new way for developing ultrahard and wear-resistant metallic alloys, which eliminates the complex and costly composition design and thermalmechanical processing routes typically required to harden conventional steels and alloys.

中文翻译：

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从软到超过 1000 HV 的超硬：通过释放 β-Mn 沉淀的潜力来设计 FeMnAl(Cu) 中熵合金的硬度


超硬耐磨金属合金对于工程应用承受长期磨损至关重要。然而，制造具有不同硬度水平的多组分合金在成分设计、加工优化以及在不同合金系统中应用硬化技术方面提出了挑战。在这里，我们展示了一种通过常规时效过程诱导 β-Mn 沉淀来制造具有灵活硬度的超硬 FeMnAl(Cu) 低密度中熵合金 (MEA) 的简便方法。该方法通过在时效几个小时内控制 FeMnAl(Cu) 低密度 MEA 中 β-Mn 的沉淀，实现从相对较软 (210 HV) 到超硬 (1042 HV) 的广泛可调硬度。快速时效引起的硬化响应赋予这些 FeMnAl(Cu) MEA 优异的抗磨损损坏能力。这些发现为开发超硬耐磨金属合金开辟了新途径，消除了传统钢和合金硬化通常所需的复杂且昂贵的成分设计和热机械加工路线。