Sigma phase detection in duplex stainless steel by induced magnetic field

8th Brazilian Congress on Metrology

Silva, E.M.^1 ; Fialho, W.M.L.^1 ; Silva, H.F.B.M.^2 ; Leite, J.P.^2 ; Leite, J.P.^3 ; Oliveira, A.V.G.^4

Institute Federal de Educação Ciência e Tecnologia da Paraíba, Av. Primeiro de Maio, 720 - Jaguaribe, João Pessoa

PB

58015-435, Brazil^1

Universidade Federal da Paraíba Jardim Universitário, S/n - Castelo Branco, João Pessoa

PB

58051-900, Brazil^2

Universidade Federal de Campina Grande, R. Aprigio Veloso, 882, 58429-900, Brazil^3

Instituto Federal de Educação Ciência e Tecnologia Do Ceará, R. José Quintino, s/n, Prado, Cedro

CE

63400-000, Brazil^4

关键词: Duplex stainless steel;    Field lines;    Hall-effect sensors;    High hardness;    Induced magnetic fields;    Sigma phase;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/733/1/012070/pdf
DOI  :  10.1088/1742-6596/733/1/012070

来源: IOP

【 摘 要 】

Duplex stainless steels when subjected to temperatures above 600 ° C have its tenacity decreased by the formation of sigma phase. This phase has high hardness and is rich in chromium and reduces the matrix of this element. In this study, field line density measurements, obtained in the reversibility region of magnetic domains, and application of artificial neural networks are used to monitor the formation of this undesirable phase. Samples of a stainless steel SAF 2205 were subjected to aging at temperatures of 800 ° C and 900 ° C, in order to obtain different amounts of sigma phase. The amount of this phase was obtained by image processing and the density of field lines through a Hall Effect sensor. Charpy impact tests were performed. The field lines densities were used for training of an artificial neural network and correlated with the presence of sigma phase and embrittlement of the material. The results showed that the method was able to correlate the parameters studied with the presence of the sigma phase and toughness of the material studied in both temperatures.