Ref.: MmePr30-008
Apresentador: Deivison Daros Paim
Autores (Instituição): Paim, D.D.(Universidade Federal de Santa Catarina);
Resumo:
Powder metallurgy is an important material processing technique, particularly metal matrix composites production. The worldwide market for such materials yielded revenue of US$589 million in 2022 and is anticipated to reach US$984 million by 2029. In recent years, various studies have been conducted to investigate the potential influence of nanomaterials as reinforcement phases in composite materials. Carbides, oxides, or nitrides are chosen as reinforcing materials due to their strength and stiffness. The techniques involving the in situ reinforcement phase generation have emerged as a viable synthesis route for these materials. This particular technique entails chemical reactions that lead to the formation of a refined ceramic phase within a metallic matrix. Consequently, the interface between the matrix and reinforcement becomes contamination free, thereby reinforcing the bond at the interface and subsequently improving the mechanical properties of these materials. In this context, the plasma-assisted nitriding process can be considered as an alternative for the treatment of metallic powders in metal matrix nanocomposite manufacture. Consequently, the nitride phase formation and dispersion onto the iron matrix can be regarded as the in situ reinforcing phase formation. These aspects motivated the development of a prototype reactor as a means of evaluating a novel technique for plasma-assisted powder processing. The reactor comprises a rotary drum in which iron powder samples are exposed to a plasma nitriding atmosphere. The plasma was generated by a DC power source, with the drum serving as the anode. An auxiliary heating system surrounding the drum allowed for sample heating control, and an electronic system was used to regulate the drum rotation speed and evaluate its influence on particle agitation. The reactor was located within a vacuum chamber, and treatments were carried out under low pressure. The preliminary findings indicate that it is feasible to generate stable plasma within the rotating drum. Heating profiles of samples arranged in the drum-anode configuration were conducted. Moreover, it was observed that the iron powder particle motion is correlated with the average particle size. Smaller particles tend to agglomerate more, impairing dispersion during the processing. This research exhibits potential as the proposed methodology could serve as a novel approach for nanocomposite manufacturing, enabling the incorporation of the strengthening phase directly into the raw material.