Nanomechanics Based Determination of In-Situ Toughness of Bone

University Of Texas At San Antonio, San Antonio TX

Investigators

Abstract

Abstract The research objective of this award is to develop and verify a nanoscratch methodology in measuring the in situ toughness of a class of materials that are brittle in nature but allow for appreciable plastic deformation, such as bone and tooth. A novel mechanistic model of the nanoscratch test is derived using a synergetic approach of both analytical and empirical processes based on the assumption that a failure flow occurs along the shear planes in front of the sliding tip during the scratch process. The efficacy of this method in detecting the local resistance of bone tissues to failure (toughness) is verified using bone specimens with known fragility. Deliverables include a mechanistic model of scratch process, testing procedures and associated techniques, experimental validation of the test methodology, documentation of research results, engineering education and research experiences for students from high school to graduate levels. If successful, this unique methodology will enable direct, quantitative, and minimal destructive measurements of in situ failure behavior of bone or other materials alike, thus facilitating the development of physically sound constitutive models of these materials at ultrastructural levels and the applications in the field of materials and biomedical research. In addition to bone research, other potential applications of this methodology include the characterization of biomaterials in tissue engineering, thus giving rise to great potential for advancement towards improved treatments of congenital diseases, traumatic injuries, and degenerative processes of bone tissues. The results will be disseminated to allow for adding new functions to the existing nanotechnology in materials characterization. As a broad educational component of this project, the comprehensive research program will benefit graduate, undergraduate, and high school students with integrated training opportunities in materials science, biomechanics, and nanotechnology in both classroom and research labs.