Affiliations: [a] Laboratory of Nondestructive Testing, University of
Rio de Janeiro, Rio de Janeiro, Brazil | [b] Brazilian Center of Physical Research, Rio de Janeiro,
Brazil
Correspondence:
[*]
Corresponding author: Maria C.L. Areiza, Laboratory of
Nondestructive Testing, University of Rio de Janeiro, 21941-596, Rio de
Janeiro, Brazil. E-mail: [email protected]
Abstract: Avoiding accidents caused by equipment failure and ensuring
structure quality are some of the challenges of the petroleum industry.
Petroleum exploitation in salt-water has required the use of special materials,
such as duplex stainless steels (DSS), that support highly aggressive corrosion
conditions and, at the same time, are ductile facilitating equipment
manufacture. But DSS can be embrittled when exposed to some heat treatments,
such as welding (T > 800 deg). Deleterious phases might
precipitated in this material, especially sigma phase
(σ), which appears in higher volumetric fraction. This
paper presents a proposal of a characterization procedure of deleterious phases
in DSS using Eddy Current Technique (EC). A calculus model was elaborated using
finite elements. The model was able to reproduce the behavior of this type of
steel, and it will help to correctly recognize the signals generated by the
material's internal defects.
Keywords: Duplex, characterization using eddy current, detecting deleterious phase in duplex
