A multireflection and multiwavelength residual stress determination method using energy dispersive diffraction

Abstract

Multireflection grazing-incidence X-ray diffraction was used to investigate the structure and residual stress gradients in the near-surface region of mechanically treated titanium samples. The development of this method by using a white synchrotron beam during an energy dispersive diffraction experiment is proposed.

Gradient of Residual Stress and Lattice Parameter in Mechanically Polished Tungsten Measured Using Classical X-rays and Synchrotron Radiation

“…In this work, the so-called Laplace space methodology based on AD (with Cu Kα radiation) and ED (with synchrotron radiation) techniques [22][23][24][25][26][27] was applied to measure stresses r ij and stress-free lattice parameter a 0 in the near surface layer of the mechanically polished tungsten. In this methodology, during the experiment, the information gauge is determined by exponential attenuation of the beam intensity, which can be characterized by penetration depth τ, defined in Figure 1.…”

“…It should be stated that the classical ED-ψ method [27,31] provides information from relatively greater depths when high energy synchrotron radiation is used instead of characteristic X-ray spectra, but the spatial resolution of this analysis is relatively low. Therefore, in this work, the MMXD method was applied, [24] and in the analysis, the volume of the investigated sample was divided into separate thin layers. As the result, the stresses were determined layer by layer with better spatial resolution compared to the classical ED-ψ method.…”

“…In the used MMXD method, [24] the residual stress analysis is based on the ED-ψ synchrotron X-ray diffraction measurement performed for multiple hkl reflections. The measurements were performed in the reflection w-mode (cf., Figure 2(b)) for / = 0 and 90 deg, in steps of Dw = 4 deg for w = (0 deg; 72 deg) and Dw = 2 deg for w = (74 deg; 80 deg).…”

“…For this study, nondestructive diffraction methods of the residual stress measurements using classical characteristic X-rays or synchrotron radiation are the most preferred. Hence, two methods, i.e., the multiple-reflection grazing incidence X-ray diffraction (MGIXD) [21][22][23] based on angular diffraction (AD) and multiple-wavelength X-ray diffraction (MMXD) [24] based on energy diffraction (ED), were applied in the present study. Such experimental techniques offer several benefits, among them the possibility to measure the depth profile of the residual stress being one of the most important ones.…”

Reassessment of evaluation methods for the analysis of near-surface residual stress fields using energy-dispersive diffraction

“…This pioneering work in the field of ED-XSA inspired the application of other XSA methods developed primarily for angle-dispersive (AD) diffraction, such as the multi-wavelength method (Eigenmann et al, 1990) and the scattering vector method (Genzel, 1994), to the energy-dispersive case (Genzel et al, 2004). The evaluation techniques transferred to the ED mode and used for depth-resolved residual stress analysis also include the Rietveld method (Rietveld, 1967(Rietveld, , 1969, as demonstrated by Apel et al (2014), and the multireflection grazing-incidence diffraction method (De Buyser et al, 1991;Van Acker et al, 1994;Baczmań ski et al, 2004), as shown very recently by Marciszko et al (2018).…”