A Comparison of MAPS and Synchrotron X-Ray Methods: Stresses Measured in Railway Rail Sections

The MAPS technique is an emerging technology for measurement of residual stresses in industrial components. It has a unique on-site capability to rapidly inspect products, large and small, during manufacturing or in-service. However for commercial acceptance it is important to compare and validate its performance with other methods. This paper provides one such validation for a cut section of worn railway rail. The synchrotron X-ray method was used for the comparison as it can provide a high-resolution strain map over the surface of components with sufficient measurement penetration for this sample. Comparison is made of the vertical and transverse stress fields evaluated from data for each technique. For MAPS, resolved stress components were calculated from the principal stresses and axes. For the synchrotron technique stresses were calculated from orthogonal strain data.