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A computational thermodynamics approach has been employed to design CoCrFeMnNi-based medium- and high- entropy alloys (M/HEAs) with systematically varied compositions (Co((80-X)/2)Cr((80-X)/2)FeXMn10Ni10 with x = 30, 40, and 50 at.%) and phase stability. Since the formation of sigma phase, usually brittle and undesirable, is a common concern, when this class of alloys is subjected to elevated temperatures (600–1000 ◦C), predicting its formation becomes essential. Thus, its formation and the phase equilibria were studied using the CALPHAD method, and two empirical methods, namely, valence electron concentration (VEC) and paired sigma-forming element (PSFE). Isothermal aging treatments at 900–1100 ◦C for 20 h were performed, since CALPHAD and VEC/PSFE predictions diverged. Both prediction methods were compared with experimental characterization by a combination of scanning electron microscopy and high-energy synchrotron X-ray diffraction. The predictions from the VEC/PSFE and CALPHAD calculations (depending on the database used) were shown to be quite accurate. 

This work proposes a methodology for designing high-strength precipitation-hardened high entropy alloys (HEAs) with an FCC matrix and L12 precipitates. High-throughput solidification calculations were conducted using the CALPHAD method, evaluating 11,235 alloys in the Cr-Co-Ni-Al-Ti system under specific boundary conditions. The acquired information was used to filter the alloys, focusing on alloys exhibiting an FCC+L12 phase field at 750 °C, a solidification interval narrower than 100 °C, and a solvus temperature under 1100 çC. The filtered alloys were analyzed to estimate their solid solution and precipitation hardening contributions to yield strength, with antiphase boundary energy (APB) assessed using two models. Three alloys were selected for testing the proposed strategy, including one with the highest yield stress and others for comparison. These alloys were produced, processed, and characterized using DSC, synchrotron XRD, SEM, and TEM. The results showed that the desired microstructure was achieved, with the alloys consisting of an FCC matrix and a high-volume fraction of L12 precipitates. Tensile tests at room temperature, 650 °C, 750 °C, and 850 °C demonstrated that the proposed model predicts well the yield strength trends, demonstrating the potential of the proposed approach for accelerating the discovery and development of novel HEAs with tailored properties. 

Zero-Knowledge proofs are a cryptographic technique to reveal knowledge of information without revealing the information it- self, thus enabling systems optimally to mix privacy and trans- parency, and, where needed, regulatability. Application domains include health and other enterprise data, financial systems such as central-bank digital currencies, and performance enhancement in blockchain systems. The challenge of zero-knowledge proofs is that, although they are computationally easy to verify, they are computationally hard to produce. This paper examines the scala- bility limits of leading zero-knowledge algorithms and addresses the use of parallel architectures to meet performance demands of applications.