Crystal Whisker Growth on Porous Coatings Lorraine F. Francis, Department of Chemical Engineering and Materials Science, University of Minnesota The goals of this research are to elucidate the mechanism of crystal growth for needle-like KCl whiskers on the surfaces of solution saturated porous coatings, to control the whisker dimensions, and to explore the applications of the whiskers. Year 3 Results: A systematic study of whisker growth on porous coatings under controlled experimental conditions was conducted, and results interpreted with transport models. (2) Visualization results show that salt solution rises to much higher levels in porous coatings than water (3) Whiskers form on bare substrate when nanoparticles are included in salt solution. This process is faster and requires lower relative humidity than whisker formation on porous coatings. Porous Coating Whisker Growth Zone Glass Substrate Initial liquid level Final liquid level Initial liquid level Salt Solution Reservoir Final liquid level Humidity Control Chamber Experiment set-up for whisker growth on porous coating. Digital images of whiskers grown on porous coating from solution of varying KCl concentration. Digital image of whiskers grown on bare substrate with nanoparticles in solution