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The 10 vol% ZrMgMo3O12/2024Al composites were fabricated using the powder metallurgy process and consolidation via vacuum hot pressing. The effects of the ball milling process and solution treatment time on the composites’ microstructure, Vickers hardness, and compressive properties were studied. Increasing the ball milling speed and extending the ball milling duration reduce the size of ZrMgMo3O12 particles, resulting in a more uniform dispersion within the aluminum matrix. Extending the solution treatment duration facilitates the dissolution of more primary Al2Cu phase into the aluminum matrix reducing the presence of coarse primary Al2Cu phase and increasing the number of fine Al2Cu precipitates formed during the aging process. The results indicated that an appropriate increase in ball milling speed, extension of ball milling duration, and solution treatment time can enhance the Vickers hardness and room temperature compressive strength of the composites. Specifically, the composites processed with a ball milling speed of 350 rpm for 6 h, a solid solution treatment at 495 °C for 24 h, and an aging treatment at 190 °C for 8 h exhibited a Vickers hardness of 277 HV and a compressive yield strength of 687 MPa, along with a compressive strain of 7.8 %.

NbxCu0.3Cr2Fe2Ni3Mn2 (x = 0, 0.2, and 0.4; named Nb0, Nb0.2, and Nb0.4, respectively) high-entropy alloys (HEAs) were prepared using arc melting process. The effect of Nb content on the microstructure and corrosion behavior of HEAs in HNO3 solution was studied. Nb0 and Nb0.2 alloys are composed of a single FCC phase, whereas Nb0.4 alloy is composed of FCC + Laves phase. In 10% and 30% HNO3 solutions, the immersion corrosion rate and potentiodynamic polarization corrosion rate of the HEAs showed a trend of first increasing and then decreasing with the increase in Nb content. After 30 days of immersion corrosion, Nb0.4 alloy exhibited the lowest average corrosion rate in 10% and 30% HNO3 solutions, with values of 4.6 × 10−3 and 2.8 × 10−3 mm/yr, respectively. Potentiodynamic polarization corrosion showed that Nb0.4 alloy also had the lowest corrosion current density and average corrosion rate in 10% and 30% HNO3 solutions, with values of 1.74 × 10−5, 5.56 × 10−6 A/cm2 and 0.18, 0.06 mm/yr, respectively. In addition, The Rpo of Nb0.4 alloy are 91 times and 8737 times higher than those of Nb0 alloy, respectively, and has the largest relative thickness of the passivation film. Therefore, Nb0.4 alloy exhibited the best resistance to HNO3 corrosion, mainly because adding Nb reduced the segregation of Cu, thereby weakening the corrosion effect of the primary battery. Meanwhile, Nb could play a stabilizing role in the passivation film of the alloy. The formation of corrosion-resistant Laves phase also correspondingly improved the HNO3 corrosion resistance of the alloy.