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1. 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 (BMG) 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 Prof. J.P. Chu of Taiwan, this Materials World Network program aims to design such films and to understand the fatigue mechanisms. • Findings: • Constitutive response of metallic glasses near a glass-transition temperature, Tg (Fig. 1) – aiming to develop a predictive micromechanical model with a direct connection to shear-banding kinetics • Fatigue-crack initiation caused by substrate slips can be suppressed by a strong interface adhesion and thin-film ductility (as accommodated by shear bands) – a high-resolution transmission-electron-microscopy image of a Zr-based metallic glass film on a stainless steel substrate (Fig. 2) Fig. 1: Rate-dependence of Au-based BMG near its Tg Shear bands and microstructures are of critical importance to understand the fatigue-crack initiation behavior Shear band ? Film Glass-forming thin film Sub-strate Substrate slip bands can be suppressed by thin-film plastic deformation Slip band Fig. 2: A proposed fatigue-initiation mechanism and preliminary microstructural evidence 100 nm

2. Materials World Network: Structures and Mechanical Behavior of Metallic-Glass Thin Films Peter K. Liaw, University of Tennessee Knoxville, DMR 0909037 PI (Liaw) discusses metallic-glass research at a poster session of the Spallation Neutron Source Workshop (Jan. 2010) at the Oak Ridge National Laboratory Metallurgical and Materials Transactions A, Vol. 47, No. 7, July 2010 -- Special Issue of Symposium on Bulk Metallic Glasses VI (TMS Annual Meeting, San Francisco, CA, 2/15-2/19/2009), edited by P.K. Liaw, H. Choo, Y.F. Gao, & G.Y. Wang of The University of Tennessee Co-PI (Gao) with his high-school students and undergraduate as part of the 2010 UT Math and Science Center Summer School (for rural county high schools in East Tennessee) 2010 TMS Annual Meeting & Exhibition, Symposium on Bulk Metallic Glasses VII, sponsored by TMS/ASM Mechanical Behavior of Materials Committee, organized by P.K. Liaw, H. Choo, Y.F. Gao, & G.Y. Wang, held at Seattle, WA, 2/14-2/18/2010