The Laser Induced Surface Improvement (LISI) process was developed by the University of Tennessee Space Institute and utilizes Nd-Yag lasers to melt selected precursor material with the substrate of interest to form a durable and environmentally resistant surface finish. The LISI process can be tailored to produce a superior surface with minimum, if any, or negligible impact on the base material. This includes better wear and corrosion resistant properties for materials that lack these characteristics. LISI surface treatment of aluminum 6061 and 7075 with tungsten carbide, and steel 1010 with chromium and nickel have been studied in 3.5% by weight NaCI solution. Cyclic polarization scans, salt fog evaluation using a modification of ASTM B-117 Standard, and non-destructive surface techniques like energy dispersing analysis of x-rays (EDAX) and scanning electron microscopy (SEM) were performed on select LISI samples. A correlation of data obtained has been performed and presented here.
Keywords: Aluminum alloys, ASTM B-117, EDAX (energy dispersing analysis by x- rays), corrosion, chromium alloying, cyclic polarization scans, LISI (laser induced surface improvement) process, marine environment, nickel alloying, SEM (scanning electron microscopy), steel alloy, surface evaluation, tungsten carbide