A comparison of the use of critically refracted longitudinal waves and magnetic Barkhausen noise for stress measurement in API 5L X70 steel

Abstract

According to acoustoelastic theory, ultrasonic wave velocity varies as a function of the state of stress in a body. In ferromagnetic materials, stress alters magnetic domain walls created by cyclic magnetic excitation and affects the amplitude of magnetic Barkhausen noise signals. In this work, both these properties are used to measure different levels of stress in specimens of API 5L X70 steel. Time of flight of ultrasonic critically refracted longitudinal (L cr) waves and magnetic Barkhausen noise are measured and compared using three parameters: sensitivity, linearity, and dispersion. The results show that while magnetic Barkhausen noise is much more sensitive to variations in stress, the time of flight values fit a linear curve better. Also, for the ultrasonic technique, dispersion between the curves for the different specimens is lower. For both techniques, measurement dispersion in the specimens when no stress is applied is high. The findings of this study can be used to indicate the limits within which each technique can be used and to help decide when it is more appropriate to use one technique rather than the other.

Ultrasonic Based Non-destructive Testing Technique for Predicting Shape Defects in Rolled Steel Sheets

“…Both the techniques were compared in terms of sensitivity and repeatability for residual stress measurement. 13) It was reported that the repeatability in ultrasonic technique is higher than magnetic barkhausen technique. Hence in this paper, ultrasonic based residual stress measurement technique (in particular Lcr Wave technique) has been used for predicting bow/crossbow in hot rolled sheets.…”

Non-destructive monitoring of tensile of mild steel samples by magnetic Barkhausen and ultrasonic methods

“…It uses the variation of ultrasonic wave velocity as a function of stress level on the base of the acoustic-elastic theory. Internal stress measurement can be classified into groups according to the different type ultrasonic waves (longitudinal, transverse, longitudinally refracted and surface waves) [3][4][5][26][27][28][29][30]. The choice of NDT information parameters is difficult because of complexity of many factors such as microstructure features and stresses.…”

“…The choice of NDT information parameters is difficult because of complexity of many factors such as microstructure features and stresses. The complicated problem has a solution by applying several NDT methods based on different physical approaches [1][2][3][4][5][6][7].…”

Método analítico para cálculo da velocidade de onda ultrassônica longitudinal em materiais compósitos

“…MPa, o que é bastante aceitável para as principais aplicações de ensaios não destrutivos em Engenharia. Isso é verdade porque, conforme pode ser encontrado na literatura, a técnica possui resolução em torno 18 MPa para a medição de tensão (Pereira Jr, Grijalba and Santos, 2016). Além disto, a viabilidade da aplicação das equações (4.50), (4.51), (5.1), ( 5.2), (5.3) e (5.4) pode ser justificada ao ressaltar-se as particularidades no comportamento mecânico de materiais compósitos, conforme será discutido a seguir.…”