Characterization of Residual Stresses and Microstructural by Technique of Magnetic Barkhausen Noise of API 5L X80 Steel Heat Treatment

Abstract

Residual stresses typically are generated during the manufacturing process of mechanical components. The non-destructive techniques are quite sensitive to these residual stresses, and to microstructural changes resulting from thermal cycling. In this work, samples of API 5L X80 steel were exposed to several conditions of cooling, under water, air and oil, thus obtaining different microstructures and different levels of residual stresses. The residual stress measurements were made using the methods of Magnetic Barkhausen Noise and X-ray diffraction.

Interpretation of Magnetic Barkhausen Noise Bursts in Low Frequency Measurements

“…In recent studies, MBN data has been compared with X-ray diffraction and hole drilling method [15,16]. In these experiments, the hole drilling method was performed with a hole with 2 mm of depth, but with extensometer placed at the surface [15,16].…”

“…In recent studies, MBN data has been compared with X-ray diffraction and hole drilling method [15,16]. In these experiments, the hole drilling method was performed with a hole with 2 mm of depth, but with extensometer placed at the surface [15,16]. Thus, some variation of presented results [15,16] should be due to the fact that these different techniques (MBN, X-ray diffraction, and hole drilling) assess stress at different depths.…”