Residual Stresses in Steel Plates after Shot-Blast Treatment: A High-Resolution Neutron Diffraction Study

Using high-spatial-resolution (~0.2 mm) neutron diffraction, we examined the residual stresses in structural alloyed steel (Cr, Si, Mn) plates, 5 mm in thickness, following shot peening. The analysis revealed that residual stresses form not only near the treated surface but throughout the entire thickness of the plate. Compressive stress zones appear near both treated and untreated surfaces, while tensile stress zones emerge in the middle region. The intensity of the shot peening affects the width of these zones and the magnitude of the maximum stresses. Neutron experiments were conducted to measure stresses near the treated surface of the plates, employing the sin²ψ method. Results obtained via the sin²ψ neutron method were consistent with those from traditional three-component strain measurement techniques. The sin²ψ neutron method proves to be advantageous for measuring stresses near the surfaces of thick samples, since it lacks the limitations of traditional measurement techniques on the thickness of the sample.