From bridges and skyscrapers to engines and tools to cars and airplanes, metals are the backbone of a thriving economy. Indeed, our consumption of aluminum, copper, lead, lithium, titanium, and other metals continues to rise as the global population increases and economies advance.
As world economic activity continues, higher performance alloys are needed to advance industrial production. Lightweight alloys are required for more fuel-efficient vehicles. Durable, non-corrosive alloys are needed to build longer-lasting structures. And new alloys are being sought to develop missiles, satellites, and warships that can withstand extreme temperatures.
Discovering the secrets to metal performance
To achieve goals such as these, academic and industrial institutions are working to create alloys that are lighter, stronger, more durable, and more corrosion resistant. And with the help of scanning and transmission electron microscopy and other multimodal data acquisition techniques, they are discovering the secrets to alloy performance at multiple scales, opening up new opportunities for innovative applications.
Throughout history, humans have known that adding small amounts of elements to a metal to form an alloy can dramatically change its properties. During the Bronze Age, for example, ancient civilizations added tin to copper to make tools and weapons. Later, the Romans and the Ancient Chinese mixed tin with mercury to build mirrors and armor.
Today, scientists have the ability to examine alloys at the atomic level, leading to a far deeper understanding of their physical properties and how they perform in real-world conditions. By examining the structure and composition of alloys at multiple scales, researchers can spot tiny defects in the full context of the area in which they occur.
Designing better alloys for a range of applications
One academic center that’s using electron and focus plasma ion beam microscopy and femto-second laser to explore metals and alloys is the Henry Royce Institute for Advanced Materials in the UK, where researchers are developing high-performance metals for use in the transportation, aerospace, nuclear, and healthcare sectors. By examining the relationships among the elements that form different alloys, researchers are gaining a better understanding of why alloys break down. This, in turn, is leading to the design of new, highly flexible alloys that have a lower environmental impact and can be developed at lower cost.
To assess the engineering integrity of alloys, researchers at the Henry Royce Institute are characterizing them in three dimensions using a suite of electron and X-ray microscopes along with correlative microscopy techniques that enable them to examine these alloys down to the nanometer scale. Using the correlative workflows to coordinate their research, scientists seamlessly pass samples between microscopes, allowing them to examine how alloys perform using different resolutions and fields of view.
Take an additively manufactured Inconel 718 test component for aero engines, for example. Researchers may want to use a 3D micro X-ray computed tomography to inspect large defects, cracks and component imperfections to examine nondestructively its morphology and define locations for further investigations with different apparatus. Using DualBeam or TriBeam systems (FIB-SEM, PFIB-SEM, fs-Laser-PFIB-SEM) they can explore in 3D the alloy’s microstructure and composition at much greater resolutions. Furthermore, with the help of a transmission electron microscope (TEM), they can examine a tiny region of interest at atomistic resolution, such as the tip of a crack. Utilizing multi-scale correlative imaging in this way, researchers are making the small improvements needed to create alloys of the future.
Images show results of correlative microscopy and tomography techniques applied to IN718 additively manufactured specimen. (a) visualization after X-ray micro CT scan; (b) visualization after high resolution micro CT scan; (c) visualization of combined multimodal data; (d) the crack tip segmented and visualized, including TEM study (e) and (f) tri-beam serial sectioned material volume with large opened cracks, segmented and visualized.
“What I’m interested in is why things break,” explains Regius Professor Philip Withers, Chief Scientist at the Henry Royce Institute. Using imaging across many different scales, Withers says scientists can examine failures on a very fine level and see how they can cause larger defects that ultimately lead to failure. “If you want to understand that progress from a small nucleus to a final catastrophic failure, you need to link together different pairs of glasses,” he says.
Creating the alloys of the future
Already, scientists at the Henry Royce Institute and other institutions around the globe are achieving significant breakthroughs. Thanks to today’s researchers, high-entropy alloys are being used to build more damage-resistant nuclear power plants. Nickel-based super alloys are being refined to develop jet engine components that are even more heat-resistant. Lightweight magnesium alloys are being developed to create more fuel-efficient vehicles. And titanium alloys are being employed to design stronger, more corrosion-resistant medical implants.
“The Royce has been set up to accelerate the invention and take up of new materials systems that will meet global challenges, enhance industrial productivity and competitiveness, and shape the world around us,” – Regius Professor Philip Withers, Chief Scientist at the Henry Royce Institute
To learn more about how Thermo Fisher instruments can be used to analyze metals, please visit our Metals webpage.
Bartłomiej Winiarski, PhD, is a Scientist at Thermo Fisher Scientific.