Metal Finishing has been a focus of the Energy, Environment, and Manufacturing Technology Access Project funded under the Technology Reinvestment Project (TRP), a National Institute of Standards & Technology's (NIST) Manufacturing Extension Project. Under this Project, the Environmental Protection Agency's (EPA) Common Sense Initiative (CSI) created a joint project, the Hard Chrome Pollution Prevention Demonstration Project. The Project's purpose was to help small and medium sized hard chrome electroplating shops meet the January 1997 compliance deadline for the EPA's Chromium Emissions standard. The work reported in this report was done under this project. During the Project it was noticed that surface tension measurements made by stalag-mometer did not agree with surface tension measurements made by precision tensiome-ters. The lack of agreement was further investigated. Three precision tensiometers were used. One stalagmometer was used also. Three sets of hard chrome electroplating bath samples containing wetting agent containing mist suppressant were tested by all four devices. The difference in measurement devices continued. Three different wetting agent containing mist suppressants were used to prepare know volume concentrations and the surface tensions were measured by the four devices. The results of this experiment are reported and indicate that the stalagmometer surface tension measurements will be up to 33 dynes/centimeter higher than tensiometer measurements. The surface tensions of a hydrocarbon surfactant. Ultralvory dish detergent was tested and the results were the same as for the mist suppressants. It was seen that chromic acid with mist suppressant does not follow the same change in surface tension as water does. The effect of sample temperature was investigated in this report and seen to significantly change the surface tension readings.
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