Findings :

1. a b Materials World Network: Structures and Mechanical Behavior of Metallic-Glass Thin FilmsPeter K. Liaw, University of Tennessee Knoxville, DMR 0909037 • Goals and Objectives: • While bulk metallic glasses (BMGs) are brittle, metallic-glass thin films can be ductile and lead to enhanced fatigue resistance of structural materials coated with these amorphous films. • In collaboration with Profs. J.P. Chu, Y.C. Wang, and P.L. Sun of Taiwan, this Materials World Network program aims to design such films and to understand the fatigue mechanisms. • Findings: • Both the as-deposited and annealed samples obviously exhibit better fatigue resistance than the bare 316L stainless-steel substrate, as shown in Figure 1. • A mechanistic model is developed to predict the shear-band patterns based on stress states, Poisson’s ratios, coefficients of internal friction, and dilatancy factors in Figure 2 Figure 1: Stress versus number of fatigue cycles (S – N curves) for 316L stainless-steel substrates without and with the Zr53Cu29Al12Ni6 (atomic percent, at.%) glass-forming film in as-deposited and annealed conditions. Arrows indicate the run-out data after 1 × 107 cycles without failure. Figure 2: (a) Radial and (b) circular-type shear bands in bonded metallic-glass plates under micro-indentation. Interface constraints “reflect” radial shear bands but out-of-plane shear bands end at the interface.

2. Materials World Network: Structures and Mechanical Behavior of Metallic-Glass Thin Films Peter K. Liaw, University of Tennessee Knoxville, DMR 0909037 Dr. Peter Liaw teaches a graduate research course using the book on Bulk Metallic Glasses, edited by Michael Miller and Peter Liaw. His course covers the development and applications of late-transition-metal bulk metallic glasses. Metallurgical and Materials Transactions A, Vol. 42, No. 6, June 2011 -- Special Issue of Symposium on Bulk Metallic Glasses VII [The Minerals, Metals & Materials Society (TMS) Annual Meeting, Seattle, WA, 2/14-2/18/2010], edited by P.K. Liaw, G.Y. Wang, H. Choo, & Y.F. Gao of The University of Tennessee Dr. Liaw and an undergraduate student, Daniel Wentz, are currently writing a book chapter about the fatigue and fracture behavior of structural materials for the book on Mechanisms, Modelling, and Mitigations. 2010 TMS Annual Meeting & Exhibition, Symposium on Bulk Metallic Glasses VIII, sponsored by the TMS/American Society for Metals (ASM) Mechanical Behavior of Materials Committee, organized by P.K. Liaw, G.Y. Wang, H. Choo, & Y.F. Gao, held at San Diego, CA, 2/27-3/3/2011. Liaw Wentz