Microstructural evolution of V‐Ti‐B based high‐temperature alloys during surface conditioning by means of laser beam melting

Respecting the potential of additive manufacturing (AM) technologies to enhance material performance, this article presents the first results of an investigation on the use of laser beam melting (LBM) on V-Ti-B alloys. Latter possess a high melting point and low density which are required for high-temperature structural applications. The research objective is to demonstrate the feasibility of the laser beam melting (LBM) technique to create graded microstructures and therefore to modify alloy properties throughout the specimen. Two values of the laser beam power were applied. The microstructural evolution of alloys with varying titanium and boron concentrations was examined by conducting scanning electron microscopy (SEM) and energy dispersive x ray spectroscopy (EDS) analyses throughout the entire process. Hardness measurements performed in the core of the samples as well as on the laser beam treated surfaces demonstrated that the surface conditioning of the V-Ti-B alloys result in higher hardness values, with increases ranging from 70 HV 10 (approx. 5 %; alloy V–28Ti–40B; 120 W) to 500 HV 10 (approx. 33%; alloy V–28Ti–40B; 180 W) compared to the intrinsic hardness of alloys in the arc–melted conditions. ... mehrThe experimental results clearly show that the fine microstructure is more favorable for the laser beam melting (LBM) application.