Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
Influence of laser parameters on the L-PBF Processing of Inconel Superalloys: A brief review
Submission Author:
Marcio C. Fredel , SC , Brazil
Co-Authors:
Marcio C. Fredel, Milton Pereira, Guilherme Volpato
Presenter: Guilherme Volpato
doi://10.26678/ABCM.COBEM2021.COB2021-0244
Abstract
Inconel superalloys are critical materials for the manufacturing of heat-resistant components of turbine systems for transport and energy applications, which demand a combination of properties difficult to be achieved by other materials. These properties include high strength in temperatures higher than 800°C and high fracture toughness allied to high fatigue, corrosion and creep resistances. Such a performance is attained by a carefully controlled composition that, after appropriated precipitation hardening heat treatments, develops a microstructure reinforced by homogeneously-distributed coherent precipitates and grain boundary phases derived from segregation. These reinforcements, however, also increase the material hardness considerably, such that Inconel superalloys tend to present a poor workability by conventional machining methods. This property thus restrains the broadness of the applications of Inconel alloys, given the high costs associated with the post processing methods needed for the achievement of dimensional tolerances. Therefore, the processing of these superalloys by additive manufacturing (AM) techniques has been the object of research of various publications in the last couple decades, given the capabilities of AM for the production of near-net-shape components even when produced in difficult to work materials. Among these techniques, Laser Powder Bed Fusion (L-PBF), a manufacturing route that consists in the layer-wise consolidation of powder precursors after the incidence of a Laser beam in specific regions of a pre-deposited powder bed, is considered as a promising method for the production of Inconel components, given its capability to achieve high dimensional precision and low defect incidence. This manufacturing route requires, however, the optimization of a processing window, a set of machine parameters that permit the production of materials with defect control, microstructures and properties similar or superior to those produced by conventional manufacturing techniques such as forging or casting. Nonetheless, few authors amidst optimization studies analyze the impact and effects of altering laser-only parameters, once the use of standard commercial systems often make it difficult to make the changes needed in its optical system for such analysis. Therefore, this brief review aims to show the effects of laser-only parameters such as laser power, focus distance, energy profile and pulsed beam on the L-PBF processing of Inconel superalloys.
Keywords
Laser powder bed fusion, Selected Laser Melting, Laser focal shift, Energy Distribution, pulsed laser
