Women in the Industry Professor Julie Cairney

Source: Sally Wood

Professor Julie Cairney undertaking her leading research. Credit: Professor Julie Cairney, supplied.

Professor Julie Cairney is a global leader in materials science, with extensive international experience and industry knowledge. This means she is well positioned to lead the charge in materials characterisation at the University of Sydney’s School of Aerospace, Mechanical and Mechatronic Engineering.

Professor Cairney’s role is primarily focused on studying materials by using sophisticated microscopy techniques to study their matter down to the atomic scale. By analysing their microstructure, experts like Professor Cairney are able to relate it to their properties, and engineer other advanced materials with unique properties. Through this approach, Professor Cairney contributes her expertise to the development of stronger and lighter materials that are sustainable and cost effective. These materials have practical utilisation objectives in the aerospace, manufacturing and construction sectors. The professor’s humble beginnings in rural New South Wales paved the way for what she does today. Growing up in Broken Hill, in the heart of the Australian outback and a 15 hour drive from Sydney, Professor Cairney recalls meeting may engineers and geologists in her childhood. As a bright maths and science student, she knew early on that she wanted to study something in that area. She received a scholarship from Pasminco Limited – a former mining company in the area – to study a mining-related subject at the University of New South Wales (UNSW). “That was really when I first came across the materials engineering course.” “I remember seeing subjects like crystallography and x-ray diffraction on the curriculum, and thinking, ‘ooh that sounds cool’. I’m not sure I was particularly strategic or thoughtful about my choice of degree – I just went with what looked interesting,” Professor Cairney said. Professor Cairney’s experience at UNSW was where she first studied materials science and engineering, and in 2002, she was awarded a PhD in Physical Metallurgy. After completing her PhD, she was granted a Royal Academy of Engineering Research Fellowship, which saw her move abroad to work as a researcher at the University of Birmingham, in the United Kingdom. Later, she spent some time at the Max Planck Institute for Metals Research in Stuttgart, Germany, and still collaborates today with researchers that she met during that period. In 2007, Professor Cairney started an academic role at the University of Sydney, where she now heads up a group that undertake research in the field of atomic

scale materials characterisation. This group sits within the Australian Centre for Microscopy and Microanalysis, and specialises in the study of 3D structures of materials at the atomic scale. “I was lucky enough to be awarded a few grants early in my career that allowed me to set up a small research group and remain productive when I took maternity leave in 2009 and 2011,” she said. The research group consists of 15 researchers, including postdoctoral research fellows, current PhD students, undergraduate research students and international visitors. In addition to her role at the University of Sydney, Professor Cairney is also the Chief Executive Officer of Microscopy Australia – a consortium of open access microscopy facilities housed at different Australian universities. Together, over 3,500 researchers from universities and industry bodies use the facilities and expertise available through this initiative. Including over 150,000 international trainees who use their online training tools. Microscopy Australia hopes to position Australia at the forefront of global research. It has been working for enhanced excellence in research for over a decade, with government support to deliver industry solutions. Professor Cairney’s research heavily relies on access to world-class infrastructure for materials characterisation. At the Australian Centre for Microscopy and Microanalysis, Professor Cairney has access to a wide variety of technologically like advanced microscopes, to examine materials for precise characterisation. “Because our facilities are open access, all researchers can access all microscopes, so we can be strategic across Australia about what we invest in rather than compete. I’m proud of the fact that our infrastructure is available to everyone who needs it, no matter what type of research environment they come from,” Professor Cairney said. Professor Cairney is also the Director of the Australian Centre for Microscopy and Microanalysis. The Centre is the home of interdisciplinary microscopy research at the University of Sydney. “I love working with microscopes. In a parallel to astronomy, we’re able to explore the unseen world of ‘inner space’ with the amazing scientific instrumentation available today.” “I think it’s incredible that we can actually detect and visualise single atoms. To give some perspective, a single human hair is approximately the width of a million carbon 12 atoms lying side by side,” Professor Cairney said.

Professor Cairney’s research covers a wide variety of materials, including, but not limited to, steels, corrosion products, functional materials, geological materials,

Hydrogen at dislocations in steel, obtained from the CITIC Linkage project, which Professor Cairney worked on. Credit: Professor Julie Cairney, supplied. and biominerals. Professor Cairney also supervises a range of fundamental and industry-sponsored research. She employs a consultative approach to research management, providing her team with the autonomy to complete tasks and make discoveries at their own pace. Professor Cairney places a high emphasis on research utilisation objectives. She has worked with BlueScope Steel on the design of new strip cast steels that are strengthened by the atomic-scale clustering of atoms. She has also worked with Weir Minerals Australia to produce stronger, wear resistant alloys for components aimed at reducing the downtime in the Australian mining sector. These products both reached production trials.

In 2019, Professor Cairney and her colleague Dr Yi-Sheng Chen worked with Chinese company, CITIC Metal, to analyse the decrease in the ductility of hydrogen in steel. This process, known as embrittlement, typically focuses on how certain metals become susceptible to early fracture as they absorb hydrogen. “Our research will elucidate how a proposed solution, hydrogen trapping, reduces hydrogen embrittlement, contributing to design criteria for hydrogen-resistant steels. “To image the hydrogen in the steels, we replaced it with deuterium – the rarer isotope of hydrogen, allowing us to distinguish it from background noise and create 3D maps of the distribution of the hydrogen at the atomic scale,” says Professor Cairney. This research was supported by a $321,000 Australian Research Council (ARC) Linkage Project grant. In a key paper, published in Science in January of this year, the project described the process where hydrogen is trapped by microstructural defects in steel such as dislocations, grain boundaries and niobium carbide precipitates. This is key information for the design of steels that resist hydrogen embrittlement.