unh/cc-composites

1. New Promising Property of Pyrolytic CarbonIgor I. Tsukrov, University of New Hampshire, DMR 0806906 Outcome: researchers at the University of New Hampshire have discovered a previously unknown mechanical property of pyrolytic carbon. Experiments show that this important constituent of carbon/carbon composites has different stiffness in tension and compression. Impact: This newly discovered phenomenon can be utilized to design stiffer and lighter composites with application-tailored response. Explanation: Chemical vapor infiltrated carbon/carbon composites have a complex hierarchical microstructure that has to be considered on submicron (nanotexturedpyrolytic carbon, PyC), micro (transversely isotropic infiltrated fiber bundles) and meso (porous fiber-PyC system) length scales. One of this year’s thrusts has been measurement of elastic properties of bulk PyC. The stress-strain curves obtained by the in-plane tension and compression tests are superimposed in the plot of Fig.1. The most remarkable finding is the existence of the tension-compression anisotropy in the bulk pyrolytic carbon. The in-plane Young’s modulus measured in tension (E2, E3 = 30.2 GPa) is significantly higher than if the sample was loaded in compression (E2, E3 = 18.8 GPa). This tension-compression anisotropy of PyC has not been previously reported. Fig.1. Stress-strain curves obtained by the in-plane tension and compression tests on highly-textured PyC showing specimen orientation and location of strain gages for each elastic constant www.unh.edu/cc-composites

2. School Teacher in Research Blog Igor I. Tsukrov, University of New Hampshire, DMR 0806906 Dawn Korade, Technology and Design Teacher with the Academy for Science and Design (ASD, Merrimack, NH), spent this past summer living on-campus learning and actively participating in research conducted on the Mechanical Engineering (ME) Department at UNH. During this time she kept a detailed blog followed by her ASD students (6-8 grades) where she shared all her experiences and new knowledge gained at UNH. One of the pages on this blog is devoted to the Carbon/Carbon Composites project. In the beginning of this school year Dawn held a meeting with other teachers at the Academy for Science and Design where they talked about the best way of incorporating the information about the UNH ME projects into the Technology and Design courses curriculum. Over the course of this semester the students will learn about the work conducted at UNH including research on Carbon/Carbon Composites. Fig.2. The page about carbon/carbon composites on Dawn Korade’s “Teacher in Research” blog Fig.3. Dawn Koradeoperating CNC machine on the Mechanical Engineering Department, UNH http://teacherinresearch.wordpress.com