Date of Award
M.S. in Engineering Science
A collaborative study was conducted to examine the degradation of commercially pultruded uni-directional e-glass composites. The case study specimens, including a variety of commercially pultruded polyester/e-glass and vinylester/e-glass composites were exposed to corrosive environments, namely: distilled water (h2o), bleach (naclo), and hydrochloric acid (hcl) for a minimum of 60 days, and the degradation was analyzed. Such a study was chosen on two accounts, 1) to contribute viable data to industry and research and 2) to provide data to be used to develop a standardized practice to characterize the durability for pultruded composites used for structural applications. A control group was tested without any exposure at room temperature using ASTM D6641-09 and ASTM D2344-13 for compressive properties (strength and modulus) and short-beam strength, respectively. Values obtained were then compared to their respective exposed values. Statistical analysis including coefficient of variation (COV), retention rates, and average percent weight change were calculated from the data obtained to determine what effect each corrosive environment had on the specimens and which, if any test method provided the most repeatable results. It was ultimately determined that short-beam strength data yielded the lowest COV values and thus provided the most consistent uniform data, CLC strength gave the first glance at deterioration yielding retention rates 5-10% lower than short-beam strength, and in many instances, an inverse relationship between average percentage weight change and retention rates was found.
Hedgepeth, Ryan Keith, "A Study Of The Mechanical Behavior Of Composite Materials Exposed To Corrosive Environments" (2016). Electronic Theses and Dissertations. 1069.
Emphasis: Mechanical Engineering