School of Mechanical, Materials and Mechatronic Engineering, UOW
SEMINAR Improving the Fracture Toughness of Bulk Metallic Glasses by Thermomechanical Treatments SPEAKER Prof Jamie J. Kruzic WHERE SMART 6.210 DATE Tuesday 8th of November 2016 TIME 12:30-1:30 pm
ABSTRACT Bulk metallic glasses (BMGs) are viewed as potential structural materials because they can exhibit impressive combinations of mechanical properties including extraordinary tensile yield strength (~1 – 5 GPa is common) and large elastic strain limit (~2%). Furthermore, some ductile BMG alloys based on Zr or Pd are reported to have excellent fracture toughness that may rival some of the best conventional metal alloys. In addition to these outstanding mechanical properties, BMGs soften and flow above the glass transition temperature giving good formability that enables near net-shape fabrication. However, while notched toughness values for bulk metallic glasses (BMGs) tend to be consistently high, large variability has been reported in in pre-cracked mode I fracture toughness and such scatter is seen even for a single BMG composition. Such uncertainty in the mechanical properties will limit potential applications. In this presentation it will be discussed how the observed fracture behavior is related to the internal structure of the BMG samples, and how high toughness behavior can be induced by creating favorable metallic glass structures. The effects of thermomechanical treatments such as cold imprinting, cold rolling, and cryogenic thermal cycling on fracture toughness will be presented. In general, such treatments are shown to 1) ductilize pre-cracked bending beams, 2) reduce the observed scatter in the fracture toughness, and 3) achieve high toughness behavior typical of notched samples. Overall, these results suggest that thermomechanical treatments are an easily accessible means to induce favorable glass structures that promote improved fracture toughness behavior.
ABOUT THE SPEAKER Jamie J. Kruzic is a Professor at School of Mechanical and Manufacturing Engineering, UNSW Australia. He got PhD on 2001 at University of California, Berkeley (1998-2001) in Materials Science and Mineral Engineering. After that, he worked as Post-Doctoral Fellow at Lawrence Berkeley National Laboratory (2001 – 2004); Assistant Professor (2004 – 2008), Associate Professor (2008 – 2014), Professor (2014 – 2016) at School of Mechanical, Industrial, and Manufacturing Engineering, Oregon State University.
He has published 79 Journal articles, 2 book sections, and 25 conference papers. Web of Science: >2000 cites, h-index = 26.
He was awarded Helmholtz W3 Professorship Award, Helmholtz Association, Germany (2015); Friedrich Wilhelm Bessel Research Award, Alexander von Humboldt Foundation, Germany (2011); Faculty Researcher of the Year, Oregon State University, School of Mechanical, Industrial, and Manufacturing Engineering (2011); Arthur E. Hitsman Faculty Scholar, Oregon State University, College of Engineering (2009 – 2012); Promising Scholar Award, Oregon State University (2009); Erasmus Mundus Fellowship (2009); Top Reviewer Award, Journal of the Mechanical Behavior of Biomedical Materials (2008); Young Leader Professional Development Award, TMS - The Minerals, Metals, and Materials Society (2007); CAREER Award, National Science Foundation (2006); Engelbrecht Young Faculty Award, Oregon State University, College of Engineering (2006); John G. Maurer Graduate Fellowship (2000-2001); Regents of the University of California Graduate Fellowship (1998); John H. Wheeler and Elliott H. Wheeler Graduate Fellowship (1996); Inducted into Tau Beta Pi and Phi Kappa Phi Honor Societies (1995).
Prof. Jamie J. Kruzic
School of Mechanical and Manufacturing Engineering
Sydney NSW 2052, Australia
Ph. +61 293 854 017 firstname.lastname@example.org