Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Characterization of Nanocomposite Powders for Additive Manufacturing
Submission Author:
Gustavo Scheid Prass , SC
Co-Authors:
Gustavo Scheid Prass, Victor Chastinet, Ana Sofia D'Oliveira
Presenter: Gustavo Scheid Prass
doi://10.26678/ABCM.COBEM2023.COB2023-1472
Abstract
Additive manufacturing (AM) of metallic parts include a set of techniques where three-dimensional objects are built up layer by layer using metallic powder or wire as feedstock. The use of metallic powder has its own advantages, such as the ability to blend different powders to obtain customized chemical compositions, which drives innovation in the development of new materials. In this context, nanocomposite powders can be introduced to AM processes to take advantage of their unique properties. Nanocomposite powders are materials consisting of a carrier powder, generally microparticles (MPs), and one or more types of nanoparticles (NPs) that are distributed on the MPs surface. Characterization of the nanocomposite powders is important to understand their behavior during the additive manufacturing process and to select processing parameters, leading to the production of defect-free parts with desired properties. In this study, different powder compositions were obtained by individually mixing AISI 316L with 1 wt% Cu MPs, Cu NPs, and CuO NPs. The mixtures with NPs were carried out in two steps, the first mixture was done in a mechanical mixer with pure ethanol to avoid agglomeration of the NPs and the second mixture was done in a Y-type mixer after drying (50ºC for 24 h). AISI 316L and Cu MPs both range from 75 to 150 µm as measured by dynamic image analysis (DIA). Cu NPs and CuO NPs have average particle sizes of 500 nm and 30 nm, respectively, according to the manufacturer. Scanning electron microscopy (SEM) was used to analyze powder morphology, SEM images showed that the electrolytic Cu MPs are irregular with a dendritic-like morphology and gas-atomized AISI 316L particles are mostly spherical, with satellite particles. The MPs had some porosity that was not observed in the multilayers processed by plasma transferred arc (PTA). Cu NPs and CuO NPs adhered to the surface of the carrier particles in a well-distributed manner. Energy-dispersive X-ray spectroscopy (EDS) confirmed the composition of powder mixtures. Powder flowability was evaluated using a Hall funnel with dried (80ºC for 2 h) and non-dried powder mixtures. Results showed that powder mixtures containing NPs required drying before the deposition to mitigate the negative impact of humidity on powder flowability. Deposited multilayers processed with nanocomposite powder mixtures have a similar density to those processed with atomized stainless steel, whereas powder mixtures containing Cu MPs resulted in denser multilayers.
Keywords
Additive manufacturing, AISI 316L, Cu, CuO, Nanocomposite Powder
