Abstract A relatively low density nanocrystalline high entropy alloy (HEA) with a nominal composition of Al20Fe20Mg20Ni20Ti20 is synthesized through the mechanical alloying process. The synthesized HEA is comprised of the mixture of bcc and fcc solid solution with crystallite size of the order of 6 to 7 nm. To understand the phase stability, the synthesized HEA is annealed at 200 °C and 500 °C for 2 hr. The 200 °C annealed HEA does not show any significant change in the XRD pattern. However, annealing at 500 °C affects the relative volume fraction of the formed phases. The synthesized Al20Fe20Mg20Ni20Ti20 HEA showed better magnetic characteristics with Ms (54.28 emu/g) and Hc (43.4 Oe) as compared to the many of recently reported HEAs. Moreover, for 200 °C annealed HEA, the found value of Ms (54.92 emu/g) and Hc (42.4 Oe) is similar to the as-synthesized HEA. An interesting change in magnetic behaviour has been observed after annealing at 500 °C, which may be related to the change in the fcc to bcc phase volume and change in the lattice parameter of these phases.

中文翻译：

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一种新型低密度半硬磁性Al20Fe20Mg20Ni20Ti20高熵合金

摘要 通过机械合金化工艺合成了一种标称成分为Al20Fe20Mg20Ni20Ti20的相对低密度纳米晶高熵合金(HEA)。合成的 HEA 由 bcc 和 fcc 固溶体的混合物组成，晶粒尺寸为 6 至 7 nm。为了解相稳定性，合成的 HEA 在 200 °C 和 500 °C 下退火 2 小时。200 °C 退火的 HEA 的 XRD 图案没有显示任何显着变化。然而，在 500 °C 下退火会影响形成相的相对体积分数。与最近报道的许多 HEA 相比，合成的 Al20Fe20Mg20Ni20Ti20 HEA 显示出更好的磁特性，具有 Ms (54.28 emu/g) 和 Hc (43.4 Oe)。此外，对于 200 °C 退火的 HEA，Ms (54.92 emu/g) 和 Hc (42. 4 Oe) 类似于合成的 HEA。在 500 °C 退火后观察到磁行为的有趣变化，这可能与 fcc 到 bcc 相体积的变化以及这些相的晶格参数的变化有关。