A University of Queensland scientist is among a team of international researchers bringing us closer to a new generation of steel and metal alloys. What’s wrong with what we currently have? Well, at the moment we have an issue with hydrogen absorbing into metals and making them brittle – and it has meant massive failures in major engineering and building projects.
But it looks like embrittlement may soon be a thing of the past.
Professor Roger Wepf, Director of the UQ Centre for Microscopy and Microanalysis said embrittlement has been a known issue for 140 years.
“The current generation of these metals can suffer hydrogen embrittlement, where they become brittle and fracture due to the accidental introduction of hydrogen during manufacture and processing,” he said. “A major example of alloy embrittlement occurred in 2013, when bolts in the eastern span of the San Francisco-Oakland bridge failed tests during construction.”
The problem occurs because hydrogen is extremely volatile and diffuses quickly, Dr Weft says.
“Our research collaboration has, for the first time, localised and visualised hydrogen in steels and alloys,” he said. “This is essential for the development of new alloys with greater endurance.”
Dr Weft and his team have shown that it’s possible to localise hydrogen at atomic resolution – at the scale of a single atom – or at a nanometre (less than one-billionth of a metre) scale. They do this by using a combination of techniques, including cryo electron microscopy freezing, low-temperature sample preparation in a cryo focused ion beam microscope, and inert cryo-transfer.