CCRAA
Independent Researcher
June 2009- September 2010
College Cost Reduction and Access Act (CCRAA)
Grant Overview
The College Cost Reduction and Access Act is a federal grant that provides research funding to the STEM disciplines. Undergraduate students are eligible for awards over the academic year or over the summer.
Abstract
Composites are an increasingly important class of engineering materials, and are beginning to replace traditional materials in many applications. Cutting edge projects, such as Tesla’s electric sports car and Boeing’s flagship 787 Dreamliner, extensively use composite material in their designs. However the physical properties of composites still aren’t completely understood because of the complexity of their internal structure. Traditional materials such as steel are uniform, meaning the material is exactly the same throughout. Composites, however, are created from two or more materials. As a result, the details of the interactions of the materials within the finished part can significantly alter the physical properties of the part. Some of the factors that affect the performance of a composite include fiber type, fiber weave, epoxy type, and manufacturing process. This project explores the effect of weaving the fibers on the properties of the composite. Two sets of composite specimens are manufactured and tested. Both sets are made from the same fibers in the same orientations, have the same matrix, and have the same fiber volume fraction. The only difference between the two sets of specimens is that the first set is made of woven fiber cloth, while the second is made of alternating plies of unidirectional fibers. The carbon fiber tensile specimens were manufactured using a standard vacuum infusion process. Standard tensile specimens were tested to determine the effect of fiber configuration on the composite’s elastic modulus (E), strength (Ksi ), Weibull modulus and failure mechanisms. Differences were found in all three measures favoring the unidirectional plies. However the woven plies failed less catastrophically. These differences may be attributed to the kinked nature of the woven cloth, which acts out of plane and adds positive contact between 0 90 fibers and surrounding layers but holds the composite together at failure.
My Research
After competing with over 30 students I was one of the final 8 to receive funding for the 2010 academic year. The grant came with a stipend as well as 800 dollars for research. Unlike other research projects I was in control of my project, deciding all aspects of my research. I had to choose what I bought, when I bought it and had to teach myself the theory and the practice. Utilizing the 800 dollars and an old GE vacuum pump I taught myself everything needed to properly laminate composites. In 10 weeks through reading, practice and patience I figured out what materials were needed, where I could get them and how I had to use them to vacuum bag a carbon fiber sample. In the next 10 weeks I made 48 test coupons and then taught myself how to performed another more advanced process known as vacuum infusion.
Utilizing the samples I created I performed the strength analysis, analyzed and compiled my results and have presented at various research conferences including the National Conference for Undergraduate Research. At the time of writing I have been accepted to speak at every conference I have applied.
Unidirectional Tensile Test