Non-destructive Residual Stress Measurement Research Articles

Nondestructive residual stress measurements in railroad wheels using the low-field magnetoacoustic test method: Namkung, M.; Utrata, D. Review of progress in quantitative nondestructive evaluation, Williamsburg, Virginia (United States), 22–26 Jun. 1987. Vol. 7B, pp. 1429–1438. Edited by D.D. Thompson and D.E. Chimenti, Plenum Press, 1988.

Nondestructive residual stress measurements in railroad wheels using the low-field magnetoacoustic test method: Namkung, M.; Utrata, D. Review of progress in quantitative nondestructive evaluation, Williamsburg, Virginia (United States), 22–26 Jun. 1987. Vol. 7B, pp. 1429–1438. Edited by D.D. Thompson and D.E. Chimenti, Plenum Press, 1988.

Non-destructive residual stress measurement in railway wheels, based on the magnetomechanical effect: Mutton, P.J.; Langman, R.A. Non-destructive testing - Australia, vol. 28, no. 5, pp. 130–134 (Sep.–Oct. 1991)

Non-destructive residual stress measurement in railway wheels, based on the magnetomechanical effect: Mutton, P.J.; Langman, R.A. Non-destructive testing - Australia, vol. 28, no. 5, pp. 130–134 (Sep.–Oct. 1991)

Nondestructive Measurement of Welding Residual Stresses by Acousto-Elastic Technique and Prediction of Fatigue Crack Growth

Nondestructive measurements of residual stresses were successfully attempted by the acoustoelastic technique on butt-welded joints of a carbon steel for nuclear piping. Usefulness of the technique considering the effect of the material anisotropy is emphasized. Based on the measured residual stresses, predictions of the fatigue crack growth were done using the superposition technique. It is shown that predictions agree well with experiments. The effect of the accuracy in residual stress measurements on the predictions is also included.

Nondestructive residual stress measurements in railroad wheels using the low-field magnetoacoustic test method : Review of Progress in Quantitative Nondestructive Evaluation, Williamsburg, Virginia (United States), 22–26 Jun. 1987. Vol. 7B, pp. 1429–1438. Edited by D.D. Thompson and D.E. Chimenti, Plenum Press, 1988

Nondestructive residual stress measurements in railroad wheels using the low-field magnetoacoustic test method : Review of Progress in Quantitative Nondestructive Evaluation, Williamsburg, Virginia (United States), 22–26 Jun. 1987. Vol. 7B, pp. 1429–1438. Edited by D.D. Thompson and D.E. Chimenti, Plenum Press, 1988

Nondestructive residual stress measurement in steel using magnetoacoustic interactions.

In ferromagnetic materials, ultrasonic velocity varies with both stress and external magnetic field. This phenomenon occurs due to the magnetoelastic interactions, and it is called magnetically induced velocity change (MIVC). The behavior of MIVC depends on the stress, magnetic field, ultrasonic mode (longitudinal or shear), and their relative orientation including the polarization direction of the shear wave. Its magnitude is of the order of 10-5, being comparable with the acoustoelastic effects. In the present study, the MIVC for longitudinal and polarized shear waves were first measured with mild steel specimens for the changing magnetic fields applied parallel or perpendicular to uniaxial stresses. The MIVC curves thus obtained showed salient dependence on the stress. They were then used to nondestructively evaluate the thermomechanical residual stress introduced by gas cutting. The results agreed with the strain gage measurements and the conventional acoustoelastic methods, both destructive, showing the usefulness of the MIVC method to measure residual stresses nondestructively. The MIVC was found to be insensitive to the micros-tructures.

Non-destructive measurement of residual stress by magnetostriction effect II (stress - field measured by magnetic probe) : Yoshinaga, A.; Abe, J.; Nakano, M.; Endo, K.; Takizawa, C. Journal of Japanese Society Non-Destructive Inspection, Vol. 37, No. 9, pp. 730–736 (Sep. 1988)

Non-destructive measurement of residual stress by magnetostriction effect II (stress - field measured by magnetic probe) : Yoshinaga, A.; Abe, J.; Nakano, M.; Endo, K.; Takizawa, C. Journal of Japanese Society Non-Destructive Inspection, Vol. 37, No. 9, pp. 730–736 (Sep. 1988)

Nondestructive residual stress measurements in railroad wheels using the low-field magnetoacoustic test method : Namkung, M.; Utrata, D. Review of progress in quantitative nondestructive evaluation, Williamsburg, Virginia (United States), 22–26 Jun. 1987. Vol. 7B, pp. 1429–1438. Edited by D.D. Thompson and D.E. Chimenti, Plenum Press, 1988

Nondestructive residual stress measurements in railroad wheels using the low-field magnetoacoustic test method : Namkung, M.; Utrata, D. Review of progress in quantitative nondestructive evaluation, Williamsburg, Virginia (United States), 22–26 Jun. 1987. Vol. 7B, pp. 1429–1438. Edited by D.D. Thompson and D.E. Chimenti, Plenum Press, 1988

Nondestructive residual stress measurements in railroad wheels using the low-field magnetoacoustic test method Namkung, M.; Utrata, D. Review of progress in quantitative nondestructive evaluation, Williamsburg, Virginia (United States), 22–26 Jun. 1987. Vol. 7B, pp. 1429–1438. Edited by D.D. Thompson and D.E. Chimenti, Plenum Press, 1988

Nondestructive residual stress measurements in railroad wheels using the low-field magnetoacoustic test method Namkung, M.; Utrata, D. Review of progress in quantitative nondestructive evaluation, Williamsburg, Virginia (United States), 22–26 Jun. 1987. Vol. 7B, pp. 1429–1438. Edited by D.D. Thompson and D.E. Chimenti, Plenum Press, 1988

Nondestructive measurement of welding residual stresses by acoustoelastic technique and prediction of fatigue crack growth.

Nondestructive measurements of residual stresses were successfully attempted by the acoustoelastic technique on butt-welded joints of a piping carbon steel plate. Based on the measurements and evaluations of the residual stresses, the prediction of the fatigue crack growth was done using the superposition technique, and results 'were compared with the experiments. The measurement of the initial residual stress distribution on the specimen before the fatigue test and the application of a proposed evaluation method of the material anisotropy can give a more correct prediction, The sensitivity of possible errors in the acoustoelastie measurement was analyzed and discussed.

Non-Destructive Measurement of Residual Stresses in U-0.8 WT% Ti by Neutron Diffraction

ABSTRACTThe macroscopic residual stress distribution in γ-quenched and stress levelled U-0.8wt% Ti alloy tubes was studied using neutron diffraction techniques. Residual strains were evaluated from the difference in d-spacings measured in the tubes and in small reference samples machined from each tube. Residual stresses were calculated with the isotropic bulk values of the elastic constants for polycrystalline α-U. Quenching from the γ field resulted in a nearly equi-biaxial stress state at every point across the wall thickness of the tube. The magnitude of the radial stress was very small compared with that of the axial and hoop stresses which were compressive at the surfaces and tensile in the interior. Stress levelling relieved almost completely the hoop residual stress without affecting the radial stress. The axial residual stress becomes tensile through the wall thickness and remains constant at about 20% of its magnitude in the as-quenched condition.

Acoustoelastic stress measurement using magnetically induced velocity change.

The stress dependency of magnetically induced velocity change (MIVC) is studied on a welded joint of carbon steel with particular reference to the influence of the structure anisotropy on MIVC. The advantage of the present method using MIVC is cleared in comparison with the conventional method. The results obtained are as follows: (1)The magnetic field dependency of MIVC is insensitive to the structure anisotropy of base and weld metals. (2)The effect of stress on MIVC is equivalent to the effect of magnetic field. The stress dependency of MIVC is insensitive to the structure anisotropy of base and weld metals. (3)The present method using MIVC is more effective than the conventional method because of its insensitivity to the structure anisotropy. The present method is available to nondestructive measurements of residual stresses.

弱い直交異方性体の音弾性関係の一般化

Since the anisotropy of ultrasonic SH wave velocities in plates was shown available to the nondestructive measurement of residual stress, much attention has been paid to the direction-dependence of propagation characteristics of ultrasonic waves. In this paper, it is intended to extend the acoustoelastic relation in slightly orthotropic materials to an arbitrary propagation direction of plane elastic waves. At first, the perturbation method was applied to the eigen value problem of the general acoustical tensor, and the formal solutions were obtained within the first-order of stress and the second-order of elastic anisotropy. Then these solutions were applied to the case where the effects of stress and anisotropy are of equal degree, and the velocities and polarization directions were explicitly expressed within the first-order of stress and anisotropy as the functions of the angles θ and φ specifying the propagation direction with respect to the principal axes of orthotropy. From these expressions, which are approximate but practically sufficient, the results previously obtained by Iwashimizu et al., King et al., and Thompson et al. were rederived by specializing the propagation direction. Finally, the simplification of the general relations was considered by imposing those restrictions on the anisotropic parameters, which are suggested by the theoretical analysis of macroscopic elastic constants of textured polycrystalline aggregates.

Measurement of residual weld stresses by acoustoelastic technique. (Evaluation of material anisotropy).

An acoustoelastic technique is useful for nondestructive measurements of residual weld stresses. It is difficult, however, to distinguish the influence of the residual stresses and of the material anisotropy on results. In this study, a new method to evaluate the material anisotropy is proposed. To confirm its applicability and utility, experiments were performed using butt weld joints of a carbon steel. The results obtained are follows; (1) In the weld metal, a discontinuous point is found in addition to a minimum point on the oscilloscope traces of received echos as the ultrasonic transducer is rotated. (2) Based on the above result, a new method to separate the influence of the material anisotropy from that of the residual stress is proposed. Its applicability and utility are confirmed experimentally. (3) The material anisotropy of the weld metal is much stronger than that of the base metal.

Effects of stress on magnetically induced velocity changes for surface waves in steels

Results of an experimental investigation of the effects of uniaxial stress on the magnetically induced velocity changes for 5-MHz surface (Rayleigh) waves in specimens of ASTM A-36, SAE 4340, and HY-80 steel are described. Like the magnetically induced velocity changes for ultrasonic shear and longitudinal waves, the magnetically induced velocity changes for surface waves exhibited characteristic stress effects which were dependent on the magnitude and the sign (tensile or compressive) of the stress as well as on the relative orientation of the stress, the magnetic field, and the wave propagation directions. The observed characteristic stress effects indicated potential applicability of the magnetically induced velocity changes for surface waves to nondestructive measurements of residual surface stresses in ferromagnetic structural steels.

Angular dependence of the Rayleigh wave velocity in polycrystalline metals with small anisotropy

An analytical expression for the angular dependence of the Rayleigh wave velocity on polycrystalline metals with small anisotropy is obtained with the use of the variational method. For a Poisson ratio v = ¼ this corrects the result obtained by M. L. Smith & F. A. Dahlen ( J. Geophys Res . 78, 3321-3333 (1973)), by using the same method. Application is made to the Rayleigh wave velocity in hot rolled aluminium and steel sheets. The results are shown to agree with the exact results obtained earlier for propagation along the principal axes of weakly textured metals with orthorhombic symmetry, this being the symmetry of rolled sheet. The results can be applied to the non-destructive measurement of residual stress in metals.

Nondestructive residual-stress measurement on the inside surface of stainless-steel pipe weldments

The instrumentation, technique, and procedures are described for the nondestructive measurement of residual stresses on the inside surface of pipe as small as 10 in. in diam. The instrument is based upon a unique position-sensitive scintillation X-ray detector which provides for the most compact X-ray stress-measurement instrument available since the introduction of film cameras four decades ago. This instrument is capable of applying the single-exposure technique of X-ray stress measurements which results in unprecedented rapidity of stress measurement consistent with excellent precision and accuracy. The results of testing the precision and accuracy of the instrument on a zero-stress powder and four-point-bend specimen are given. Residual stresses in four austenitic stainless-steel girth-welded pipes are presented illustrating the effects of the different welding procedures. The results from the pipes confirm the beneficial residual-stress condition of heat-sink-welding procedures.

Displacement Errors in the Application of Portable X-Ray Diffraction Stress Measurement Instrumentation

The role of residual stresses in the premature failure of metallic components has long been recognized. However, the most prevalent methods of measuring these stresses are at least partly, if not completely, destructive. This, as well as the availability of more rapid and portable x-ray diffraction instrumentation, has led to a renewed interest in this nondestructive residual stress measurement methodology.

R-value Acoustoelastic Analysis of Residual Stress in a Seam Welded Plate

R-value acoustoelastic analysis method (R-method) is proposed for a nondestructive residual stress measurement. Application of this method to the measurement of residual stress in a seam welded plate shows it to be promising with the potential to measure residual stress within an error of 10 MPa.

Nondestructive residual-stress measurement in a wide-flanged rolled beam by acoustoelasticity

X-ray stress analysis is a standard nondestructive stress-measurement technique, but its use is limited in the sense that only a surface layer is surveyed. Recently, acoustoelasticity has emerged as a technique for nondestructive stress analysis. Acoustoelasticity makes use of stress-induced acoustic-birefringent effects. It gives stress distributions averaged through the thickness of a specimen. This technique is attractive because it does not require a transparent plastic model as photoelasticity does. However, much should be done before this method is established as a standard nondestructive technique of stress analysis. The most important among them is to separate stress-induced birefringence from that introduced by texture structure. For special cases, such as axisymmetric stress distributions and when a stress-free region is knowna priori, residual-stress distributions can be evaluated nondestructively. In this paper, we measured residual-stress distribution in a wide-flanged rolled beam by using a recently developed T-type transducer. The results were compared to those obtained from conventional destructive methods.

Laser Sénarmont biascope for residual surface stress measurement of float glasses

The gas laser-Sénarmont compensator-biascope combination has enabled non-destructive measurement of residual surface stresses in float glasses using the optical waveguide effect in tin-diffused surface layers. The biascope can detect surface stress as low as 10 kg cm -2. Annealing and elastic deformation effects in glasses are clearly identified.