Eventos Anais de eventos
COBEF 2021
11th Brazilian Congress on Manufacturing Engineering
NITRETAÇÃO E ENVELHECIMENTO SIMULTÂNEO LIGA NAB VIA PI3: INFLUÊNCIA DA TEMPERATURA NA DUREZA SUPERFICIAL
Submission Author:
João Miguel De Oliveira Alves Silva , PR , Brazil
Co-Authors:
João Miguel De Oliveira Alves Silva, Bruna Schibicheski Kurelo, Gelson B. de Souza, Silvio Francisco Brunatto
Presenter: João Miguel De Oliveira Alves Silva
doi://10.26678/ABCM.COBEF2021.COB21-0256
Abstract
In nickel-aluminum bronzes (NABs), the solubilization treatment (quenching) results in a refined metastable structure known as the β ' phase retained or martensite of the Cu-Al system. This phase is supersaturated in Ni and Fe, due to the suppression of the eutectoid reaction of this alloy system. The subsequent aging treatment allows intermetallic phases of the ĸ group (kappa), enriched mainly with Ni and Fe, to precipitate in a finely dispersed manner in the matrix. This combination of treatments increases the hardness, wear-resistance, and corrosion resistance of these alloys in marine environments, making these alloys suitable materials for marine propellers subject to cavitation erosion. In this work, the Plasma Immersion Ion Implantation (PI3) nitriding process of a previously solubilized NAB alloy was designed in order to simultaneously perform its aging. In this case, the PI3 process acted both as a heat source, to perform the referred heat treatment, and as a nitrogen source, to perform the thermochemical treatment involving both the ion implantation and the diffusion of the interstitial Nitrogen in the studied alloy. The samples were analyzed by Nanoindentation and X-Ray Diffraction. Greater gains in hardness only due to the aging of the treated material were obtained according to the applied voltage (voltage) was lowered and, therefore, the temperature of the sample was reduced. Similarly, the addition of Nitrogen to the surface of this material allowed the NAB hardness to be raised to values above the aged condition only. The optimized treatment condition, among the three, studied of 8, 10, and 12 kV, was 8 kV, which presented a higher hardness value, both at the level of the substrate core and at the level of surface hardening, along with the nitrided samples. and simultaneously aged. In line with the hardness gains, the X-ray diffractograms indicate an increase in the contribution of the peaks related to the kappa phases. Finally, as the applied tension increases, the hardness of the treated material is reduced.
Keywords
Nickel Aluminum Bronze, Plasma Immersion Ion Implantation (PI3), nitriding, aging, Nano Hardness
DOWNLOAD PDF VIEW PRESENTATION
