Agradecimentos: We would like to thank the Brazilian Nanotechnology National Laboratory, CNPEM/MCTIC for the assistance with SEM measurements; PETROBRAS for providing research funding; Tenaris Confab for the donation of the materials used in this research; and USP-EESC for the assistance with the...

Agradecimentos: We would like to thank the Brazilian Nanotechnology National Laboratory, CNPEM/MCTIC for the assistance with SEM measurements; PETROBRAS for providing research funding; Tenaris Confab for the donation of the materials used in this research; and USP-EESC for the assistance with the XRD measurements. Authors would like to acknowledge Dr Alberto Cury for his support regarding XRD analysis. J.A. Avila acknowledges CNPq (Grant No. 150215/2016-9). Dr. H. Pinto is a CNPq fellow and Dr. Freddy A. Franco G. acknowledges the Support to Research and Extension FAEPEX at Unicamp (Ref. 1424/2015) for research support. Special thanks are due to Dr. Julian Escobar for his important review and suggestions of the manuscript

Friction stir welding is a solid-state joining method conducted under large stress and strain conditions at low peak temperatures when compared to arc welding. Friction stir welding produces a large variety of microstructures and a M-shaped residual stress line profile along the cross-section of the...

Friction stir welding is a solid-state joining method conducted under large stress and strain conditions at low peak temperatures when compared to arc welding. Friction stir welding produces a large variety of microstructures and a M-shaped residual stress line profile along the cross-section of the welds. In this work, we present the use of magnetic Barkhausen noise to qualitatively assess the residual stress profile along the transverse direction of a two-pass friction stir welding butt joint on a X80 pipeline steel. Results were compared and correlated to X-ray diffraction, microstructural and hardness characterization. The peak position and the root mean square profiles of the magnetic Barkhausen noise reproduced the residual stress profile obtained by X-ray diffraction and the hardness profile, respectively. These results can be used for developing a qualitative quality control method for friction stir welding joints in other steels

CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ

150215/2016-9

Fechado