Work hardening for powder bed fusion–laser beam (PBF-LB) AlSi10Mg alloy manufactured at different orientations and its application for Vickers hardness evaluation

Abstract Powder bed fusion–laser beam (PBF-LB) is one of the additive manufacturing (AM) techniques that have grown in demand in recent years due to the ability to produce extremely lightweight, ultra-high-strength metals necessary for the aerospace industry. Aluminium alloys such as AlSi10Mg manufactured using PBF-LB exhibit anisotropic mechanical behaviour and variable plastic deformation characteristics, posing challenges for broader structural applications. This paper presents a comprehensive overview of the mechanical properties of AlSi10Mg, covering ultimate tensile stress (UTS), elongation at fracture, yield stress (YS), work hardening, hardening capacity, toughness, and hardness. Hollomon and Voce methods are used for approximating work hardening of PBF-LB AlSi10Mg printed at different orientations. Improved Hollomon and Voce approximations are presented using Levenberg–Marquardt (LM) least square method, and it is shown that improved Hollomon and Voce approximations show superior accuracy in predicting work hardening behaviour of the material compared to the original Hollomon and Voce approximations. A unique method of obtaining Vickers hardness of AM materials purely from tensile testing and use of work hardening, rather than direct hardness testing, is also presented, which potentially reduces the time and cost of hardness testing, especially in the absence of hardness testing facilities.