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Abstract Alloy powders with dual-phase nanocrystal (NC) and nanoglass (NG) have received much attention due to its small coercive force and high permeability, but the preparation of dual-phase high entropy alloy powders (HEAPs) simultaneously with larger aspect ratio constitute a great difficulty in microwave absorbing domain. Here, a new concept has been devised to tune the crystallinity of microwave absorber by regulating the phase proportion of milling precursor. A combination technology containing melting, strip casting, and milling has been adopted to prepare a serious of FeCoNiSi x Al 0.4 HEAPs to verify its correctness. Selective phase transition occurs in dry-milling process, generating various unique microstructures - NCs, NGs, and NGs embedding in NC grain. Besides, BCC phase content of HEAPs can be controlled by the amount of added ethanol. A less coercive force, increasing from 14.05 Oe (C 0.1) to 23.43 Oe (C 0.5), and a large magnetic permeability, varying from 2.41 (C 0.5) to 2.80 (C 0.3) at 1 GHz, can be obtained. Highlights • The crystallinity of powders relate to FCC phase proportion of milling precursor. • The phase structure of nanocrystal alloy ribbons can be tuned by element content. • Co-existed phase transitions promote the formation of dual-phase microstructure. • The variety of crystallinity lead to the change of magnetic properties. [ABSTRACT FROM AUTHOR]

The effect of Ti content on the microstructure and mechanical properties regulation for Fe 45 Ni 30−x Cr 15 Al 10 Ti x high entropy alloys (HEAs) with a duplex FCC/BCC structure is investigated. The as-cast Fe 45 Ni 30−x Cr 15 Al 10 Ti x HEAs have typical dendrite and inter-dendrite structure, where dendric and inter-dendric regions are FCC and BCC phases, respectively. After introducing Ti, the inter-dendric structure transforms into coexistence of disordered BCC and ordered B2/L2 1 phases. And the morphology of B2/L2 1 precipitates gradually changes from a regular maze-like mesh and cuboidal structure to elliptical structures due to the increase of the lattice mismatch. The change of precipitate type and volume fraction lead to that the ultimate tensile strength of the HEAs increases from 540 MPa to 1292 MPa. Meanwhile, it keeps the uniform elongation of 13.29%, showing outstanding strength-plasticity synergy. • A multi-phase coexistence HEA with superior mechanical property was designed. • The addition of Ti led to precipitation of hierarchical B2/L2 1 phase from BCC phase. • As the Ti content increased, the morphology of precipitates changed. [ABSTRACT FROM AUTHOR]

A new method was proposed to pinpoint the compositions with good glass forming ability (GFA) by combining atomic clusters and mixing entropy. The clusters were confirmed by analyzing competing crystalline phases. The method was applied to the Zr–Al–Ni–Cu–Ag alloy system. A series of glass formers with diameter up to 20 mm were quickly detected in this system. The good glass formers were located only after trying 5 compositions around the calculated composition. The method was also effective in other multi-component systems. This method might provide a new way to understand glass formation and to quickly pinpoint compositions with high GFA. [ABSTRACT FROM AUTHOR]