Searching for materials that possess a combination of excellent magnetic softness and vanishing magnetostriction, the ferromagnetic high-entropy alloy (HEA) system AlCoFeNiCux (x = 0.6–3.0) is investigated. Superior magnetostriction parameters are obtained composition AlCoFeNiCu2.0, which shows zero ?s 0, low coercivity Hc ? 650 A m?1 substantial saturation polarization Js 0.55 T. The other com...