Dynamic Nanomechanical Tester for Characterization of Advanced Structural Materials
Abstract
The goal of this proposal is to acquire Bruker Hysitron¨ TI Premier Dynamic nanomechanical tester with accelerated property mapping (XPMTM) and nanoscale dynamic mechanical analyzer (nanoDMA¨) features for quantitative characterization of ultrahard ceramics (B4C, B6O, SiC and their composites), nanomaterials (W and B4C), high entropy alloys (HEA), and novel multilayered graphene, all of which are potential candidates for body armor and/or penetrator applications. The XPMTM allows 6 nanoindents/s and can map hardness and stiffness over a small selected region within the microstructure. The nanoDMA¨allows determination of viscoelastic properties of coatings, gels and soft biomaterials, a subject of PIs current/future research interests. The PI currently holds three contracts with the Army Research office (ARO), Army Research Laboratories (ARL) and the Department of the Army (PEO Soldier) to investigate fundamental deformation mechanisms in advanced ceramics and multilayered graphene composites for armor applications. In the ARO project on boron-based icosahedral ceramics (B4C and B6O), the PI is investigating amorphization phenomenon using microindentation and Raman spectroscopy. However, typical microindentation cannot be used to probe the influence of sub-micron microstructural features in B6O such as nanotwinning which has been theorized to improve properties and mitigate amorphization. Similarly, in the Department of the Army project, the strength and deformation characteristics of B4C-B6O, BAM-B4C, B4C-SiC composites and multilayer (up to 5000 layers) graphene nanocomposites (100-nm thick) are being investigated. Traditional microscale indents are too large to be effective in probing the properties of individual phases and graphene layers and hence a nanoindentation system with depths in the range of few nanometers is required to obtain fundamental information on their deformation mechanisms. Finally, the PI has a pending cooperative agreement with ARL where he will investigate the mechanical behavior and microstructural deformation mechanisms of nanograined W and HEA. To successfully execute the above projects, the PI proposes to purchase a versatile instrument capable of performing high-speed low-depth nanoindents to map hardness and stiffness over the desired regions of the microstructure and conduct in-depth analyses and fundamental research. The PI also holds a DOE grant to characterize uncertainty in failure of SiCf-SiCm composites for applications in extreme environments. The accelerated nanoscale property mapping feature allows investigation of the scatter in hardness, stiffness, and failure strength to be quantified as a function of variability in microstructural features (e.g., distribution in fiber diameter, wall thickness, porosity). Additionally, the PIÕs research interests also lie in understanding the behavior of ceramic coatings, soft polymer gels and biological tissue (NSF funded) which can utilize the XPMTM and nanoDMA¨ features to measure hardness, stiffness and viscoelastic properties. The proposed Hysitron¨ TI Premier Dynamic nanomechanical tester will cost $199,000 and will serve the core mission of training students with expertise in the disciplines of interest to DoD. The PI has an established track record of training outstanding students many of whom are minority students, have excelled at national and international student paper competitions, and recipients of prestigious NSF, DOD (SMART and NDSEG), and Fulbright fellowships. Many are placed in national laboratories (ARL, SNL, ORNL, and PNNL), academia and defense industries. This DURIP funding will further elevate his research capabilities in advanced materials and training of new generation of scientists prepared to meet the challenges of the 21st century.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 04, 2021
- Source ID
- W911NF2110018
Entities
People
- Ghatu Subhash
Organizations
- Army Contracting Command
- United States Army
- University of Florida