Soft magnetic materials are vital for a wide range of technologies. However, the very diversity of these applications poses a fundamental challenge for their design and manufacturing. This is compounded by a typical trade-off: improvements in mechanical property often necessitate a sacrifice in magnetic property, thus hindering the achievement of a comprehensive performance balance.  To overcome this, we present a FeCoNi-based multi-principal element alloy fabricated via dual-powder alternately deposition additive manufacturing (AMed-AD). This approach creates a unique honeycomb-like multistage microstructure with coherent (Fe, Co, Ni)₃Al precipitates. Compared with cast counterparts, the AMed-AD alloy achieves superior tensile strength (528.4 MPa) and elongation (35.4%)―improvements of 150% and 179%, respectively―while preserving magnetic properties due to the refined, homogeneous microstructure that minimizes domain-wall pinning. Corrosion resistance is also enhanced through microstructural refinement and chemical homogeneity. DFT calculations reveal that alloying increases charge localization and interfacial bonding while reducing the density of states at the Fermi level, collectively underpinning the improved mechanical, magnetic, and anti-corrosion performance. This work offers a microstructural engineering strategy to break traditional property trade-offs in soft magnetic alloys.

Two-dimensional (2D) spintronic devices based on van der Waals (vdW) heterostructures have potential applications in magnetic sensing and data storage. Here, we report vdW heterostructures fabricated by stacking an exfoliated ultrathin black phosphorus (BP) or violet phosphorus (VP) spacer between two exfoliated ferromagnetic Fe₃GeTe₂ (FGT) electrodes. The devices achieve high magnetoresistance (MR) ratios of 40.4% and 31.5% for the FGT/BP/FGT and FGT/VP/FGT heterostructures at low temperature, respectively. The magnitude of MR can be tuned by bias current and spacer thickness. Moreover, magnetotransport measurements confirm robust spin valve effect, showing angular-independent MR in FGT-based heterostructures. Our work opens a new avenue for the application of monoelemental phosphorus as spacer in novel spintronic devices.