Simon Lockyer Bratton
Simon Lockyer-Bratton, Ph.D.
Senior Associate
Materials & Corrosion Engineering
Menlo Park

Dr. Lockyer-Bratton specializes in failure analysis, fracture, microscopy and mechanical properties of materials, and has general knowledge in both mechanical engineering and materials science. He has expertise with mechanical testing across multiple length scales using standard MTS and Instron load frames as well as custom-designed equipment for small-scale testing including tensile, compressive and tribological evaluations. Dr. Lockyer-Bratton is proficient in many characterization techniques including optical microscopy and metallography, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), electron backscatter diffraction (EBSD), X-ray diffraction (XRD) and confocal laser scanning microscopy (CLSM).

Prior to joining Exponent, Dr. Lockyer-Bratton completed his Ph.D. dissertation work at Johns Hopkins University, where he examined the interfacial fracture behavior of high temperature thermal barrier coatings (TBCs) used in jet engine turbines. He used both mechanical tests and microscopy techniques to investigate microstructural and chemical changes in TBCs during thermal cycling. He incorporated experimental results into computational models (finite element analysis) to understand the effect of crack face roughness and friction on TBC interfacial fracture toughness. Dr. Lockyer-Bratton also designed and fabricated several high temperature furnaces (>1200°C) for non-contact measurements of coefficient of thermal expansion (CTE), utilizing digital image correlation (DIC), to conduct tests on TBC bond coat materials.

CREDENTIALS & PROFESSIONAL HONORS

  • Ph.D., Mechanical Engineering, Johns Hopkins University, 2016
  • M.S.E., Mechanical Engineering, Johns Hopkins University, 2012
  • B.S.E., Mechanical Engineering, Northern Arizona University, 2011
  • Whiting School Doctoral Fellowship, Johns Hopkins University

    Mechanical Engineering Departmental Fellowship, Johns Hopkins University

Publications

Podium Presentations

Lockyer-Bratton S, El-Awady J, Hemker KJ. Experimental measurements of thermal barrier coating interfacial fracture toughness as a function of mode-mix. International Conference on Metallurgical Coatings and Thin Films (ICMCTF), April 2016.

Lockyer-Bratton S, El-Awady J, Hemker KJ. Experimental measurements of coating interfacial fracture toughness as a function of mode-mix. The Minerals, Metals and Materials Society (TMS), March 2015.

Lockyer-Bratton S, El-Awady J, Hemker KJ. Determination of the mode II interfacial fracture toughness of thermal barrier coatings with the compression edge-delamination test. The Minerals, Metals and Materials Society (TMS), February 2014.

Poster Presentations

Lockyer-Bratton S, MacSleyne J, Konitzer D, El-Awady J, Hemker KJ. Experimental measurements of thermal barrier coating interfacial fracture toughness as a function of mode-mix. UCSB Winter Workshop on High Temperature Coatings, January 2016.

Lockyer-Bratton S, El-Awady J, Hemker KJ. An experimental method for determining the mode II interfacial toughness of thermal barrier coatings. International Conference on Metallurgical Coatings and Thin Films (ICMCTF), April 2013.

Lockyer-Bratton S, El-Awady J, Hemker KJ. Determination of the mode II interfacial fracture toughness of thermal barrier coatings with the compression edge-delamination test. UCSB Winter Workshop on High Temperature Coatings, January 2013.

Professional Affiliations

American Ceramics Society

The Minerals, Metals & Materials Society (TMS)

CREDENTIALS & PROFESSIONAL HONORS

  • Ph.D., Mechanical Engineering, Johns Hopkins University, 2016
  • M.S.E., Mechanical Engineering, Johns Hopkins University, 2012
  • B.S.E., Mechanical Engineering, Northern Arizona University, 2011
  • Whiting School Doctoral Fellowship, Johns Hopkins University

    Mechanical Engineering Departmental Fellowship, Johns Hopkins University