Friction stir processing (FSP) is a novel surface modification technique based on the principles of friction stir welding (FSW). FSP modifies the microstructure and thereby increases the corrosion, wear resistance and induces superplasticity. Laser melting (LM) also improves corrosion and wear resistance . AA 2219 (Al-6.3%Cu) aluminium alloy is used in defence and strategic applications. AA 2219 is prone to corrosion in chloride environments. This book compares the effect of FSP and LM in improving the corrosion resistance of AA 2219 aluminium alloy. The amount, size and distribution of second phase particles were studied by various characterization techniques likes XRD, DSC, SEM, OM, TEM after FSP and LM. Pitting, EIS, Immersion, salt spray corrosion tests were conducted on the alloy. The book will be of great help to the material scientists, corrosion engineers, metallurgical engineers, researchers and students working in the above said fields.