Structural, Morphological, and Mechanical Properties of Laser Irradiated AA-2024-T3 Aluminum Alloy Sheet

Laser is one of advanced surface processing techniques by use of which improved wear and corrosion resistance can be achieved without any modification in the bulk material. Current research involves exposure of AA2024-T3 sheet samples having dimensions of (20x20x2 mm 3 ) to laser (InGaN diode laser of 532 nm wavelength). One sample was left unexposed while remaining samples were irradiated for 5, 10, 15, 20 and 25 minutes respectively. The irradiated samples were characterized by X-ray diffractometer (XRD), Scanning Electron Microscope (SEM) and Vickers hardness testing machine. The SEM micrographs revealed different kinds of laser ablation on the exposed surfaces. The hkl value (111) showed that the samples have single crystal and the grain size of each sample lies in nano-meters range. A monotonic increase and decrease was observed when graphs were plotted for each sample between angle of diffraction “2 θ ” and grain size. Laser exposure time and micro-hardness have a direct relation, which means that AA-2024-T3 hardness increases monotonically as time of laser exposure increases. However, maximum hardness was found at exposing the AA-2024-T3 aluminum alloy sample to laser for 20 minutes. Later on, when it was irradiated for 25 minutes, micro-hardness started to decrease.