Poster Presentation 24th Australian Conference on Microscopy and Microanalysis 2016

Interrogating the structure and chemical bonding of precipitates in alloys by quantitative convergent beam electron diffraction. (#255)

Philip NH Nakashima 1 , Yong Zhang 1 , Luke S Besley 1 , Dashen Dong 2 , Jessie L Hamilton 1 3 , Zijun He 1 , Liangcong Jiang 1 , Quan H Lai 4 , Fanyi Li 1 , Yinglei Li 5 , Xiongfeng Lin 1 , Jingying Liu 1 , Yanming Liu 5 , Luxin Luo 6 , Trina Majumdar 1 , Ashley Murphy 1 3 , Ding Peng 1 , Taposh Roy 1 , Murray J Shaw 4 , Chinmay A Sonawane 1 , Ziyu Wang 1 , Yuxiang Wu 1 , Pei Yu 1 , Bowen Zang 1 , Ke Zhang 1 , Qi Zhang 1 , Shaohua Zhang 5 , Zezhong Zhang 1 , Tianyu Liu 1 , Philip Chan 7 , Laure Bourgeois 1 8
  1. Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia
  2. Department of Chemical Engineering, Monash University, Clayton, Victoria 3800, Australia
  3. Manufacturing Flagship, CSIRO, Clayton, Victoria 3168, Australia
  4. Department of Mechanical and Aerospace Engineering, Monash University, Clayton, Victoria 3800, Australia
  5. Department of Civil Engineering, Monash University, Clayton, Victoria 3800, Australia
  6. Faculty of Engineering, Monash University, Clayton, Victoria 3800, Australia
  7. Monash eResearch Centre, Monash University, Clayton, Victoria 3800, Australia
  8. Monash Centre for Electron Microscopy, Monash University, Clayton, Victoria 3800, Australia

Experimental techniques for chemical bonding measurements have been confined to homogeneous crystalline materials. Over the last two decades, quantitative convergent beam electron diffraction (QCBED) has emerged as the most accurate and precise technique for such measurements [1 - 3] and, with recent advances, it has been suggested that QCBED may be the only way to measure bonding in nano-composite materials [4].

In this work, we present the first attempts to measure bonding in an inhomogeneous crystalline material.  We apply the multislice formalism [5] for electron scattering in our approach to QCBED (which requires the material being characterised to be sliced into layers) to examine the structures of the plate-like strengthening precipitates of the theta' and theta" phases in an aluminium-copper alloy, at atomic and electronic resolution. 

  1. [1] P.N.H. Nakashima, Phys. Rev. Lett. 99 (2007), 125506.
  2. [2] P.N.H. Nakashima and B.C. Muddle, Phys. Rev. B81 (2010), 115135.
  3. [3] P.N.H. Nakashima, A.E. Smith, J. Etheridge and B.C. Muddle, Science 331 (2011), 1583.
  4. [4] P.A. Midgley, Science 331 (2011), 1528.
  5. [5] J.M. Cowley and A.F. Moodie, Acta Cryst. 10 (1957), 609.