Magnesium alloys have one of the highest specific strengths of all construction
metals used. Specifically, magnesium alloy castings are used in the aerospace industry to
reduce the weight of aerospace vehicles. Coating systems must be employed to prevent
corrosion of these magnesium alloys as they are also the most corrosion prone
construction metals. The use of chromium is employed for the conversion coating which
forms the foundation of many of these coating systems. In an effort to phase these
harmful chromates out of the coating system and continue to use magnesium alloys, an
environmentally friendly conversion coating has been developed. This paper explores the
best types of methods used to evaluate the thickness and coating coverage of the
environmentally friendly conversion coating. Destructive and nondestructive techniques
are developed to examine the thickness and surface coverage of this environmentally
friendly coating. Specifically an eddy current measurement technique, light, confocal,
scanning electron and transmission electron microscopy techniques are used to determine
the coating thickness of the environmentally friendly coating through destructive
evaluation. Three nondestructive evaluation techniques, including polarized light
microscopy, infrared spectroscopy (Fourier Transform and Raman) and an infrared
proximity sensor are used to determine surface coverage of the environmentally friendly
coating.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/4266 |
| Date | 30 October 2006 |
| Creators | Zuniga, David |
| Contributors | Griffin, Richard B. |
| Publisher | Texas A&M University |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Thesis, text |
| Format | 6522130 bytes, electronic, application/pdf, born digital |
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