Accuracy of X-ray diffraction measurement of residual stresses in shot peened titanium alloy samples

ABSTRACT

Accuracy of residual stress measurement using the Sin^2 ψ method has become a focus in many applications where residual stress plays a critical role in components, such as aeronautics, railway welding, bearings, gears, etc. Accuracy in residual stress measurement requires consideration of both correctness and uncertainty. In this paper, a self-designed and home-made in-situ tension/compression device is adapted to evaluate the correctness of residual stress measurement in titanium alloy. A calculation method employing multiple convolutions to evaluate the uncertainty of residual stress measurement is presented. Test results show that the X-ray elastic constant is an important parameter impacting the correctness of residual stress measurement. And that the uncertainty of residual stress measurement fluctuates with the surface status of shot peened samples.

KEYWORDS:

• Residual stress
• shot peening
• accuracy
• correctness
• uncertainty

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China under Grant No. 51405059; Fundamental Research Funds for the Central Universities under Grant No. DUT16RC(4)33; Foundation of Liaoning Educational Committee under Grant No. LZ2015014.