Development and Application of the Contour Method to Determine the Residual Stresses in Thin Laser-Peened Aluminium Alloy Plates

Abstract

The contour method was applied to obtain residual stress fields in a laser-peened 2.0-mm-thick Al2024-T351 sample. In order to remove the effects of near-surface wire electro-discharge machining (EDM) cutting artefacts on the measured residual stresses, sacrificial blocks were attached to both surfaces of the thin sample with a polymer-based glue doped with silver particles. A data analysis routine based on bivariate spline smoothing was conducted to obtain a 2D residual stress map. The results were compared with incremental hole drilling, and X-ray diffraction and layer removal techniques. The results are in good agreement in terms of the magnitudes and the location of the peak stresses, with the exception of the contour method results. Owing to the low thickness of the samples, the data analysis is very sensitive to the parameters used in the spline fitting, leading to fluctuation in the results. It is concluded that the contour method can be applied to thin samples, however, extra attention is required. Since the uncertainty is higher compared to the conventional contour method results, it is good practice to compare the results with at least one other experimental method.2

Stress measurement and correction with contour method for additively manufactured round-rod specimen

“…The steel block attached to the round-rod specimen is also called the sacrificial block, as described in Ref. [15] The schematic diagram of the specimen and the after-cut section of the specimen with the sacrificial block is shown in Figure 2.…”

Effect of Input Parameters on SR and MRR for Tool Steel AISI L2 By Electric Discharge Machine (EDM)

“…Many input parameters were influenced by the surface roughness of the EDM process such as Current, Voltage, Pulse on time, Tool electrode, Polarity and Workpiece materials, type of the dielectric fluid and even electrode dimensions. High parametric effected on surface roughness was current [11].…”

Experimental and computational modeling of bulk residual stress for aeronautical components with distinct geometries

“…A more detailed two-dimensional (2D) stress map was reported using the CM, which was validated using welded [13][14][15][16][17] and laser-peened thin plates. 18,19 It should be noted that CM measurement is highly uncertain for detecting stress in the near-edge region of thin samples. Accurately measuring deformed cut-planes, appropriately selecting fitting functions, carefully processing the data, and performing additional verification are usually recommended for CM tests of thin plates.…”