Curvature Interferometry based In-Situ Measurement of Stresses Associated with Electrochemical Reactions
Omer Ozgur Capraz (Iowas State University), Pranav Shrotriya (Iowa State University), Kurt Hebert (Iowa State University)
Materials for Extreme Environments: Multiscale Experiments and Simulations
Mon 4:20 - 5:40
Salomon 203
Anodization as well as dissolution of reactive metals such as aluminum results in buildup of significant levels of stresses on the reacting surface. In-situ measurement of stress evolution can provide remarkable insights into the associated electrochemical reactions and help in understanding the governing mechanisms. We report a curvature interferometry based technique for in-situ monitoring of stress evolution. Curvature interferometer is incorporated into the electrochemical cell and is used to monitor the curvature changes of the samples in order to determine the stress-thickness product of the film formed on the reacting surface. Electrochemical cell is designed such that chemical reactions are confined on the front surface of aluminum samples. Back surface of the samples are coated with a reflective coating so that curvature interferometer can be used to monitor the sample curvature. The cell is used to monitor stress evolution in 1 mm thick aluminum samples during both anodization and anodic dissolution. Experimental results show that the curvature measurements allow high resolution measurement of in-situ stress development with curvature resolution of 100 1/km.