LPBF processed nickel-iron soft-magnetic alloys: influence of heat treatments on density, microstructure and magnetic properties

Abstract

Soft-magnetic materials have a key-role in electronics or electric actuated devices. Nonetheless, LBPF manufactured soft-magnetic materials have been rarely investigated regarding crucial processing conditions, heat treatments, microstructure and resulting magnetic properties. This study aims to provide a discussion about the microstructure of as-built material and varied heat treatment conditions of a binary nickel-iron as well as a nickel-based shielding alloy by the means of optical and electron microscopic methods (EBSD). Furthermore, the subsequent magnetic hysteresis properties are discussed. It is shown that post LBPF heat treatments of soft-magnetic materials are necessary not only to tune the magnetic properties but to improve density as well as homogeneity of the resulting microstructure in order to achieve near wrought-material magnetic properties.