19 23 35 P. 13 Metallographic Analysis of 19th Century Rail Specimen Forensic Metallurgy in Archaeology and Aerospace ASM Materials Education Foundation Update SCALE-BRIDGING CHARACTERIZATION OF ACICULAR FERRITE NUCLEATION MATERIALS TESTING/CHARACTERIZATION MAY/JUNE 2025 | VOL 183 | NO 4
Showcase your thought leadership and innovations at one of ASMʼs 2025-26 conferences and expositions, which offer unparalleled access to highly engaged audiences of industry leaders and decision-makers. INTERNATIONAL CONFERENCE ON RESIDUAL STRESSES (ICRS) OCTOBER 20 – 23, 2025 | DETROIT, MICHIGAN Discover the forefront of residual stress research and its impact on material behavior at this enriching event. Engage with experts and practitioners across diverse fields through our symposium topics, networking opportunities, and technical programming. INTERNATIONAL MATERIALS, APPLICATIONS & TECHNOLOGIES (IMAT) OCTOBER 20 – 23, 2025 | DETROIT, MICHIGAN IMAT, ASM’s annual event, is the only targeted conference on advanced materials, applications, and technologies in key growth markets that will have a focus on economic trends and business forecasts. The event will include a diverse group of materials experts, including the ASM Programming Committees and all six of ASM’s Affiliate Societies, who are heavily involved in building the technical symposiums, which will have a strong focus on realworld technologies that can be put to use today. HEAT TREAT 2025 OCTOBER 21 – 23, 2025 | DETROIT, MICHIGAN Discover the unrivaled opportunities awaiting you at Heat Treat Conference/Expo! As the LARGEST gathering for heat treating professionals, materials experts, and industry leaders in North America, Heat Treat is a MUST-ATTEND event! INTERNATIONAL SYMPOSIUM FOR TESTING AND FAILURE ANALYSIS (ISTFA) NOVEMBER 16 – 20, 2025 | PASADENA, CALIFORNIA ISTFA is the only North American event devoted to the semiconductor, electronic sample preparation, and imaging markets. ISTFA offers the best venue for failure analysts and the FA community for sharing challenges and acquiring the technical knowledge and resources needed to take them on. SYMPOSIUM ON EMERGING MATERIALS AND INNOVATIONS IN THERMAL SPRAY (SEMI) DECEMBER 1 – 3, 2025 | MELBOURNE, AUSTRALIA SEMI is a new symposium offered by the ASM Thermal Spray Society (TSS), in coordination with Swinburne University of Technology. This event will explore the latest advancements in thermal spray and cold spray technologies, with a focus on surface engineering, repair applications, and innovative materials for the mining and industrial sectors. INTERNATIONAL THERMAL SPRAY CONFERENCE & EXPOSITION (ITSC) MARCH 18 – 20, 2026 | BANGKOK, THAILAND ITSC is the world’s foremost international conference and exhibition for thermal spray technologists, researchers, manufacturers, and suppliers. This conference rotates between North America, Europe, and the Pacific Rim and is organized by the ASM Thermal Spray Society, the German Welding Society (DVS), and the International Institute of Welding (iiw). HEAT TREAT MEXICO APRIL 14 – 16, 2026 | MONTERREY, MEXICO Mark your calendars for Heat Treat Mexico 2026, the PREMIER event powered by the strength of the ASM Heat Treating Society, ASM Mexico Chapter, and Heat Treat North America Organizers. Discover cutting-edge heat treating resources, education, and technology tailored for Mexico’s flourishing markets. Secure your spot now! SHAPE MEMORY AND SUPERELASTIC TECHNOLOGIES CONFERENCE AND EXPOSITION (SMST) MAY 4 – 8, 2026 | LA JOLLA, CALIFORNIA Join us at SMST — the premier global event dedicated to the latest advances in shape memory and superelastic materials. Held in the stunning coastal setting of La Jolla Torrey Pines, this conference is a must-attend for professionals working with Nitinol and related technologies. AEROMAT JUNE 2 – 4, 2026 | WEST PALM BEACH, FLORIDA AeroMat will feature a wide range of technical topics, offering insights into the latest on innovative aerospace materials, fabrication, and manufacturing methods that improve performance, durability, and sustainability of aerospace structures and engines with reduced life-cycle costs. Learn more about each event and related exhibit and sponsorship opportunities at asminternational.org/events 2025-26 EVENTS
19 23 35 P. 13 Metallographic Analysis of 19th Century Rail Specimen Forensic Metallurgy in Archaeology and Aerospace ASM Materials Education Foundation Update SCALE-BRIDGING CHARACTERIZATION OF ACICULAR FERRITE NUCLEATION MATERIALS TESTING/CHARACTERIZATION MAY/JUNE 2025 | VOL 183 | NO 4
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WHAT’S IN YOUR 2025 MARKETING MIX? ASM INTERNATIONAL’S 2025 MEDIA KIT is YOUR GATEWAY to reaching a targeted audience of materials science and engineering professionals. ARE YOU READY TO EXPLORE HOW ASM CAN HELP YOU ACHIEVE YOUR 2025 GOALS? VIEW THE 2025 MEDIA KIT AT: WWW.ASMINTERNATIONAL.ORG/ADVERTISE-WITH-US-RESULTS/ ASM generates measurable impact by offering unparalleled access to engaging with a unique and motivated audience through integrated, omnichannel marketing capabilities. Develop a comprehensive campaign through sponsored emails, webinars, web and mobile ad placements, in-person event sponsorships, and more to target sizable audiences of decision makers in industries such as: Aerospace Automotive Heat Treating Materials Characterization & Testing Failure Analysis Shape Memory & Medical Devices Thermal Spray And more! KELLY “KJ” JOHANNS BUSINESS DEVELOPMENT MANAGER CONTACT KJ TODAY AT: KJ.JOHANNS@ASMINTERNATIONAL.ORG OR 440.671.3851
39 ASM NEWS The latest news about ASM members, chapters, events, awards, conferences, affiliates, and other Society activities. SCALE-BRIDGING CHARACTERIZATION OF ACICULAR FERRITE NUCLEATION Adrian Herges, Christoph Pauly, Frank Mücklich, and Sebastian Scholl This entry won the prestigious 2024 Jacquet-Lucas Award for Excellence in Metallography at the International Metallographic Contest held during IMAT in Cleveland, October 2024. 13 ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 2 Scanning electron microscope image with additional electron backscatter diffraction shows acicular ferrite phase structure. On the Cover: 46 SORBY AWARD CELEBRATES 50 YEARS A two-day symposium at IMAT 2025 helps to mark the 50th anniversary of the Henry Clifton Sorby Award, presented by ASM’s International Metallographic Society. FOUNDATION 101 The ASM Materials Education Foundation (ASM MEF) empowers educators and inspires students through dynamic materials science and engineering programs. ASM MEF independently raises 100% of its funding to ensure programs are free to participants. 35
4 Editorial 5 Research Tracks 10 Machine Learning 6 Metals/Polymers/Ceramics 8 Testing/Characterization 11 Process Technology 12 Emerging Technology 55 Editorial Preview 55 Special Advertising Section 55 Advertisers Index 56 3D PrintShop TRENDS INDUSTRY NEWS DEPARTMENTS Check out the Digital Edition online at asminternational.org/news/magazines/am-p ASM International serves materials professionals, nontechnical personnel, and managers worldwide by providing high-quality materials information, education and training, networking opportunities, and professional development resources in cost-effective and user-friendly formats. ASM is where materials users, producers, and manufacturers converge to do business. Advanced Materials & Processes (ISSN 0882-7958, USPS 762080) publishes eight issues per year: January/February, March, April, May/June, July/August, September, October, and November/December, by ASM International, 9639 Kinsman Road, Materials Park, OH 44073-0002; tel: 440.338.5151; fax: 440.338.4634. Periodicals postage paid at Novelty, Ohio, and additional mailing offices. Vol. 183, No. 4, MAY/JUNE 2025. Copyright © 2025 by ASM International®. All rights reserved. Distributed at no charge to ASM members in the United States, Canada, and Mexico. International members can pay a $30 per year surcharge to receive printed issues. Subscriptions: $499. Single copies: $54. POSTMASTER: Send 3579 forms to ASM International, Materials Park, OH 44073-0002. Change of address: Request for change should include old address of the subscriber. Missing numbers due to “change of address” cannot be replaced. Claims for nondelivery must be made within 60 days of issue. 19 METALLOGRAPHIC CHARACTERIZATION OF A DECAUVILLE NARROW-GAUGE RAIL Patricia Silvana Carrizo A study of a narrow-gauge rail used in agriculture in Argentina shows its chemical composition and suggests how it was processed. 23 FORENSIC METALLURGY IN ARCHAEOLOGY AND AEROSPACE Russell Wanhill The techniques used in forensic metallurgy investigations follow a similar protocol, whether the subject in question is a historical artifact or an aircraft component. 29 CASE STUDY STUDENTS FROM JAPAN AND FINLAND COLLABORATE ON STARTUP PROJECT Hidekazu Miura, Akiko Ogawa, Hideyuki Kanematsu, Koichiro Ogata, Liisa Lehtinen, Jani Pelkonen, and Juha Nurmio A unique collaboration between Japanese KOSEN and Turku University of Applied Sciences in Finland combines engineering and entrepreneurship. FEATURES MAY/JUNE 2025 | VOL 183 | NO 4 ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 3 19 29 31 23 31 TECHNICAL SPOTLIGHT HARDNESS TESTERS: KNOW THE OPTIONS FOR BEST RESULTS Learn how to select the ideal hardness testing method for specific applications and utilize new efficiencies such as automation, digital systems, and data mobility.
4 ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 ASM International 9639 Kinsman Road, Materials Park, OH 44073 Tel: 440.338.5151 • Fax: 440.338.4634 Joanne Miller, Editor joanne.miller@asminternational.org Victoria Burt, Managing Editor vicki.burt@asminternational.org Frances Richards and Corinne Richards Contributing Editors Anne Vidmar, Layout and Design Allison Freeman, Production Manager allie.freeman@asminternational.org EDITORIAL COMMITTEE John Shingledecker, Chair, EPRI Beth Armstrong, Vice Chair, Oak Ridge National Lab Adam Farrow, Past Chair, Los Alamos National Lab Yun Bai, Ford Rajan Bhambroo, Tenneco Inc. Punnathat Bordeenithikasem, Machina Labs Daniel Grice, Materials Evaluation & Engineering Surojit Gupta, University of North Dakota Michael Hoerner, KnightHawk Engineering Hideyuki Kanematsu, Suzuka National College of Technology Ibrahim Karaman, Texas A&M University Ricardo Komai, Tesla Krassimir Marchev, Northeastern University Bhargavi Mummareddy, Dimensional Energy Scott Olig, U.S. Naval Research Lab Christian Paglia, SUPSI Institute of Materials and Construction Satyam Sahay, John Deere Technology Center India Abhijit Sengupta, USA Federal Government Kumar Sridharan, University of Wisconsin Vasisht Venkatesh, Pratt & Whitney ASM BOARD OF TRUSTEES Navin Manjooran, President and Chair Elizabeth Ho man, Senior Vice President Daniel P. Dennies, Vice President Pradeep Goyal, Immediate Past President Lawrence Somrack, Treasurer Amber Black Pierpaolo Carlone Rahul Gupta Hanchen Huang André McDonald Victoria Miller Christopher J. Misorski Dehua Yang Fan Zhang Veronica Becker, Executive Director STUDENT BOARD MEMBERS Gladys Duran Duran, Amanda Smith, Nathaniel Tomas Individual readers of Advanced Materials & Processes may, without charge, make single copies of pages therefrom for personal or archival use, or may freely make such copies in such numbers as are deemed useful for educational or research purposes and are not for sale or resale. Permission is granted to cite or quote from articles herein, provided customary acknowledgment of the authors and source is made. The acceptance and publication of manuscripts in Advanced Materials & Processes does not imply that the reviewers, editors, or publisher accept, approve, or endorse the data, opinions, and conclusions of the authors. REMEMBERING FOUR FATHERS OF METALLOGRAPHY Take a stroll through the history of materials testing and characterization by flipping through this issue of AM&P. The names of four pioneers—whose work at different time periods and in disparate parts of the globe advanced the fields of microscopy and metallography— are evoked through various articles and news items. To celebrate the 50th anniversary of the Henry Clifton Sorby Award, a two-page spread in the ASM News section shares some highlights of the award’s namesake, his contribution to the industry, and our plans to commemorate the milestone with a can’t-miss, special symposium at IMAT in Detroit this October. Sorby (1826-1908), an Englishman, was the first to view an alloy structure under a visible light microscope and invented microspectroscopy. Dubbed the first metallographer, he made the initial observation of pearlite. Since 1976, ASM’s International Metallographic Society (IMS), has been honoring excellence in metallography and materials science through the Henry Clifton Sorby Award. Another IMS recognition, the Jacquet-Lucas Award, was presented to the authors of our lead article as part of the 2024 International Metallographic Contest. The award’s current name is a meld of two previous awards. At first, ASM offered a metallographic honor that in 1958 became known as the Francis F. Lucas Grand Prize Award. Dr. Lucas (1885-1968) was a Canadian-born research microscopist who spent much of his career at Bell Telephone Laboratories in the U.S. He was best known for pioneering high power and ultraviolet microscopy. In parallel, IMS originally had an image contest with a top prize named after Pierre Jacquet (1906-1967), a French metallographer. Dr. Jacquet conducted revolutionary work on surface preparation and was known worldwide as the father of electropolishing. Many also credit him for developing the fundamental methods of electron microscopy of metals and alloys, which became the groundwork for today’s techniques. In 1972, IMS and ASM agreed to combine the two contests, resulting in the Best in Show designation used today—the Jacquet-Lucas Award—honoring the legacy of both men. While Jacquet was creating samples in a European lab, one of his contemporaries—Zay Jeffries (1888-1965)—was advancing the field through his own work in the U.S. Embarking on research in the cutting-edge technology of microstructural analysis, Jeffries’ findings led to the development of grain size measurement techniques that became the foundation for modern characterization methods. He was an early proponent of the use of x-ray diffraction to study crystal structure. And he was one of the first to understand the relationship between processing, microstructure, and properties, which still holds as the basis for materials science. While spending much of his career at General Electric and Aluminum Casting Company (now part of Alcoa), he contributed to the success of many early aluminum alloys. “The Dean of American Metallurgists” is honored annually by the ASM Cleveland Chapter’s Zay Jeffries Night. I was delighted to attend this year’s event, which is featured in our Chapters in the News section. That meeting made Jeffries’ contributions come to life for me. For your own meander through time, discover artifacts in these pages that reveal how four remarkable pioneers made modern characterization possible. joanne.miller@asminternational.org
ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 5 RESEARCH TRACKS NEW COPPER ALLOY HANDLES HIGH TEMPS Researchers from Arizona State University (ASU), the U.S. Army Research Laboratory, Lehigh University, and Louisiana State University developed a new high-temperature copper alloy with exceptional thermal stability and mechanical strength. The team reports that the bulk Cu-3Ta-0.5Li nanocrystalline alloy exhibits remarkable resistance to coarsening and creep deformation, even at temperatures near its melting point. “Our alloy design approach mimics the strengthening mechanisms found in Ni-base superalloys,” says Kiran Solanki, a professor at ASU. The new alloy derives its superior properties from a unique nanoscale structure featuring precisely ordered copper lithium precipitates surrounded by a tantalum-rich atomic bilayer. Adding exactly half a percent of lithium to the previously immiscible Cu-Ta system changes its sphere-like precipitate into a stable cuboidal structure that significantly enhances thermal and mechanical performance. The Cu-3Ta-0.5Li alloy remains stable at 800°C for over 10,000 hours with minimal loss in yield strength. Further, it outperforms existing commercial copper alloys, achieving a yield strength of 1120 MPa at room temperature. Researchers say the discovery opens new avenues for next-generation copper alloys with applications in aero- space, energy, and defense industries. Potential uses include heat exchangers, high-performance electrical components, weaponry, and structural materials requiring durability in extreme conditions. asu.edu. BIODEGRADABLE PLASTIC COURTESY OF KERATIN Researchers from the Istituto Italiano di Tecnologia, University of Milano- Bicocca, and Istituto Italiano di Tecnologia via Morego, all in Italy, combined two well-known keratin processing techniques to make a new kind of bioplastic. Keratin, a fibrous protein produced by many animals, forms the main structure of hoofs, horns, feathers, hair, and other body parts. Some research projects have looked for ways to make useful products from it, but most have found it too difficult. A few current uses include powders or additives for other products. In the new study, the team found that keratin could serve as the basis for a biodegradable plastic. The researchers noted that in the past, keratin extraction was used to create long protein strands, achieved by dissolving wool in a urea and sodium metabisulfite solution. The team also noted that prior research has shown that a Michael addition could be used to link thiols in C-C double bonds, which involves placing a material in a mixture of polyethylene glycol and soybean oil acrylate. To make their new bioplastic, they similarly conducted a keratin extraction using wool and then used the results to perform a Michael addition. After cleaning, the team found that the material could be formed into solid bioplastic shapes. Further testing is required to learn more about its specific properties and commercial potential. https://en.unimib.it. The Cu-3Ta-0.5Li nanocrystalline alloy exhibits remarkable resistance to coarsening and creep deformation. Courtesy of ASU. The University of Illinois Urbana-Champaign will collaborate with Nano Nuclear Energy Inc., New York, to construct a Kronos micro modular reactor on campus. It will be the first new university research reactor to be built in nearly 30 years. illinois.edu. BRIEF Graphical abstract. Courtesy of Matter, 2025, doi.org/10.1016/ j.matt.2025.102039.
ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 6 METALS | POLYMERS | CERAMICS Grand View Research released a report estimating the global nickel mining market at $50.4 billion in 2022 with a CAGR of 6.6% through 2030. Over two-thirds of the world’s nickel is used to make stainless steel, with construction and equipment sales spurring growth in this market. grandviewresearch.com. turn saltwater and iron oxide into pure iron metal. In his team’s latest work, they optimized the starting materials for the process for potential use at an industrial scale. When the scientists began developing their process a few years ago, they started with small quantities of iron oxides from chemical supply companies. Those materials worked well in lab tests, but did not reflect the kind of iron-rich materials found naturally. As the team experimented with different kinds of iron oxides, it was clear that some worked much better than others. The new research suggests that the surface area of the starting materials is critical. The porous nanoparticles had much more surface area for the reaction to take place, making it run faster. Other iron oxides with a porous structure could also be cost-effective. “The goal is to find something that’s abundant, cheap, and that’s going to have a smaller environmental impact TINY TWEAKS HELP METALS WITHSTAND IMPACTS A research team led by Cornell University, Ithaca, N.Y., developed a method to design metals that can withstand extreme impacts—by adding nanometer-scale speed bumps that suppress a fundamental transition that controls how metallic materials deform. The findings could lead to cars, aircraft, and armor that can survive high-speed impacts, extreme heat, and stress. During rapid strains, dislocations in metals accelerate and begin interacting with phonons, which create substantial resistance. This is when a thermally activated glide transitions to a ballistic transport, leading to significant drag and embrittlement. The Cornell team worked with the Army Research Laboratory to create a nanocrystalline alloy, copper-tantalum (Cu-3Ta). The grains are so small that the dislocations’ movement would be inherently limited and further confined by the inclusion of nanometer clusters of tantalum inside the grains. To test the material, the team used a tabletop platform to launch spherical 10-µm microprojectiles that reach speeds of up to 1 km per second. Impact was recorded by a high-speed camera. Researchers ran the experiment with pure copper, then with copper-tantalum. In a conventional metal or alloy, dislocations can travel for several dozen µm without any barriers. But in nanocrystalline copper-tantalum, the dislocations could barely move more than a few nanometers before they were stopped in their tracks. Embrittlement was effectively suppressed. cornell.edu. GREENER WAY TO MAKE IRON FOR STEEL Researchers at the University of Oregon, Eugene, are developing a greener way to make iron for steel production. Last year, chemist Paul Kempler reported a way to create iron with electrochemistry using a series of chemical reactions that Copper and Brass Sales, a division of thyssenkrupp Materials North America, leased an 8000-m2 plant in Santa Teresa, N.M., to process metal for power distribution components. The center will focus on complex cutting, kitting, and just-in-time services. thyssenkrupp-materialsservices.com. BRIEFS This laser confocal microscopy reconstruction shows the impression of a spherical microprojectile impact. Courtesy of Cornell Engineering. In Paul Kempler’s lab, an electrochemical process is used to produce decarbonized iron. Courtesy of University of Oregon.
ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 7 than the alternative,” says Kempler. They are continuing their work with civil engineers at Oregon State University and an electrode manufacturing company to help scale up their designs. uoregon.edu. SEASHELLS LEAD TO SAFER PLASTICS Scientists at the University of Southern California, Los Angeles, discovered that a mineral commonly found in seashells could be used to create a safer alternative to plastic. Researcher Eun Ji Chung and her lab developed a biocompatible plastic alternative by adding calcium carbonate from seashells into poly (1,8-octanediol-co-citrate) (POC). “In graduate school, we added hydroxyapatite, which are these calcium particles that are in your bone, and I fabricated them together, and they are now biodegradable materials that are already FDA approved,” Chung says. “I started thinking that seashells have calcium, too. That’s why they’re stiff like bone. But they have a different kind of calcium particle. So, I basically adapted what I did and replicated it to be more suitable for an alternative plastic material.” Chung said the citric acid polymer’s texture is sticky. When calcium particles are added and it is heated and cured in an oven, it forms a plastic-like material. The resulting material, POC-CC, was developed into a prototype and formed into beverage holder rings strong enough to hold cans. The team believed Researchers developed a new biocompatible plastic substitute that can be used as a replacement for beverage holder rings. Courtesy of Chung Lab. that the POC-CC material could be a biocompatible plastic substitute that would degrade in marine environments while maintaining sufficient strength for industrial applications. The team is now planning an improved version of the material to help it degrade faster. usc.edu. CURED SAMPLE ABRASION RESISTANT Silicon Carbide Filled Epoxy Adhesive Supreme 45HTQ-4 www.masterbond.com ■ Robust chemical resistance ■ Serviceable from -100°F to +450°F ■ Very high compressive strength ■ Exceptionally long pot life Hobart St., Hackensack NJ, USA • +1.201.343.8983 • mainmasterbond.com
8 ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 ALUMINUM MAPPING IN ZEOLITES Researchers at The Hong Kong Polytechnic University recently discovered the precise location of aluminum atoms in a zeolite framework. Zeolites are crystalline materials widely used in the petrochemical industry that serve as catalysts in chemical production, with aluminum being the source of active sites within zeolite structures. The team believes their discovery could facilitate the design of more efficient catalysts. Zeolites are characterized by a well-defined microporous structure, high surface area, and tunable acidity and basicity, making them indispensable in petrochemical refining, environmental catalysis, and fine chemical synthesis. The distribution of substitutional aluminum atoms within the zeolite TESTING | CHARACTERIZATION STUDYING CORROSION FOR BETTER MATERIALS DESIGN New research at the DOE’s Lawrence Livermore National Laboratory, Calif., is attempting to address the widespread problem of corrosion by predicting failure to enable better materials design. Using a technique that involves advanced kinetic modeling, researchers simulated corrosion processes with both speed and accuracy and identified the effects of operating conditions and material composition. The team focused their simulation efforts on the natural protective oxide film that forms on metals to keep them intact. If the film dissolves, fractures, or becomes permeable to attack, corrosion begins. The scientists developed multiscale simulations that capture how the oxide grows, dissolves, and changes composition over time in response to environmental factors like pH and voltage. But because this approach is too difficult to use for every single material and environment, the team trained a machine learning- inspired model to predict when and why corrosion occurs. With- in this framework, researchers examined three voltage regimes. They noted that the environments with high and low voltages are well studied and understood, while the intermediate regime was more mysterious. “Until now, no one was really able to explain what exactly was going on in that regime,” says scientist Chris Orme. “We showed there is competition between two processes: dissolution and reprecipitation. When molecules leave the surface, mix and redeposit, the oxide looks completely different.” While voltage may be applied directly in some systems, like batteries, the same phenomenon is surprisingly common in other contexts as well. “Putting certain metals close to one another creates a sort of micro- battery that can drive corrosion,” explains researcher Brandon Wood. “This has been a problem in building ships and bridges, for instance. Our model can in principle account for such effects, while also being flexible enough to consider the interplay between the corrosive environment and the base metal composition.” llnl.gov. Testbed 80. Courtesy of Rolls-Royce. The team integrated synchrotron resonant soft x-ray diffraction (pictured), with molecular adsorption methods to reveal the interactions of molecules of aluminum atoms. Courtesy of Hong Kong Polytechnic University. Image of porous nickel oxide, via atomic force microscopy, formed during the dissolutionreprecipitation process. Eurofins EAG Laboratories, Columbia, Mo., opened a 6800-sq-ft microscopy lab in Phoenix to serve the semiconductor, materials science, and advanced technology industries. The lab features TEM imaging and analysis, dual-beam FIB-SEM systems, and complete sample preparation facilities. eag.com. Leica Microsystems, Germany, acquired ATTO-TEC, also in Germany, a supplier of fluorescent dyes and reagents. The specialized sample preparation products complement Leica’s portfolio of microscopy imaging platforms and AI-based analysis software. leica-microsystems.com. BRIEFS
ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 9 framework influences the geometry of molecular adsorbates, catalytic activity, and shape and size selectivity. However, accurately locating these aluminum atoms and understanding their impact on the catalytic behavior of zeolites has posed challenges for decades. In their study, the team focused on both lab-synthesized and commercial H-ZSM-5 zeolites to bridge the gap between fundamental research and practical application, optimizing H-ZSM-5 for advanced catalytic processes. The researchers used an innovative approach that integrates synchrotron resonant soft x-ray diffraction with probe-assisted solidstate nuclear magnetic resonance and molecular adsorption methods. This combination revealed the interactions of molecules at the active sites of aluminum atoms, achieving a breakthrough in locating single atoms and pairs of aluminum atoms in a commercial H-ZSM-5 zeolite. www.polyu.edu.hk. OPEN-SOURCE SOFTWARE MODELS SOFT MATERIALS Scientists at Tufts University, Medford, Mass., led by physics professor Tim Atherton, created an open-source programmable environment called Morpho that helps researchers and engineers solve shape optimization problems for soft materials. Predicting how soft and fluidic materials respond to forces is more challenging than predicting the behavior of hard materials. For example, applications of soft materials include artificial hearts and heart valves as well as robot materials that mimic flesh. The Morpho software is designed to be easy to use, free, and applicable to a broad range of scenarios. Soft materials have an inherent complexity in their response to their environment. The Morpho program models the soft materials using a finite elements approach, mathematically dividing them into small, A chiral liquid crystal membrane is simulated with Morpho so ware. Courtesy of Chaitanya Joshi and Tim Atherton. simple shapes, while equations that model materials properties, forces, and boundary constraints are generated for each node around the shapes. Then the whole system of equations is solved to predict the optimal shape of the system. “Morpho provides a set of tools to help anyone conveniently solve these problems,” says Atherton. tufts.edu. Fibercraft™ Heating Elements Offer Superior Performance in High-Temperature Applications. • Temp Range up to 1200°C (2200°F) • Exceptional Durability • Versatile Application • Customizable Design TC 8.375X5.5625_031025.indd 1 3/11/25 2:10 PM
ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 10 MACHINE LEARNING | AI A machine learning tool developed at Pacific Northwest National Laboratory, Richland, Wash., analyzes thin film growth data and flags changes as they emerge. The program lays the groundwork for systems capable of adjusting growth conditions without human input. pnl.gov. BRIEF AI SUGGESTS BEST AEROSPACE ALLOYS Researchers at Skolkovo Institute of Science and Technology (Skoltech) and the Moscow Institute of Physics and Technology, both in Russia, developed a machine learning-driven approach to quickly select promising metal alloy compositions for aerospace applications. “The current approaches rely on a fundamental physical description of the process in terms of direct quantum mechanical calculations,” says researcher Viktoriia Zinkovich. “We, on the other hand, use machine- learned potentials, which are characterized by rapid computations and make it possible to sort through all possible combinations up to a certain cutoff limit, 20 atoms per supercell, for example. That means we won’t miss the good candidates.” The new approach was validated on two systems: five metals with high melting points (vanadium, molybdenum, niobium, tantalum, and tungsten) and five noble metals (gold, platinum, palladium, copper, and silver). In each system, the team considered three elemental compositions. For example, copper and platinum or all five noble metals at once. Notably, the five elements making up each list tend to adopt the same crystal structure. This simplifies calculations because the alloy is assumed to have that structure as well. The scientists then applied their search algorithm to each of the six elemental compositions: three for the noble and three for the high-melting-point metals. The algorithm enabled the team to discover 268 new alloys stable at zero temperature that are not listed in a popular materials database called AFLOW. For example, in the niobium-molybdenum-tungsten system, the approach using machine- learned potentials produced 12 alloy candidates, whereas AFLOW contained no three-component alloys of these elements. Properties of the new alloys must be verified in greater detail with experiments to determine which materials hold promise for practical applications. https:// new.skoltech.ru. STRENGTHENING TITANIUM THROUGH AI Scientists at Johns Hopkins Applied Physics Laboratory (APL), Laurel, Maryland, and the Johns Hopkins Whiting School of Engineering are using AI to make titanium alloy parts more quickly, stronger, and with nearly perfect Brendan Croom and his team are using AI to optimize titanium alloy production. Courtesy of APL. precision. The research focused on Ti-6Al-4V and employed AI-driven models to map out previously unexplored manufacturing conditions for metal 3D printing using laser powder bed fusion. The results challenge assumptions about process limits, revealing a broader processing window for producing dense, high-quality titanium with customizable mechanical properties. “By using AI to explore the full range of possibilities, we discovered new processing regions that allow for faster printing while maintaining or even improving material strength and ductility. Now, engineers can select the optimal processing settings based on their specific needs,” says APL materials scientist Brendan Croom. Building on earlier work, the team used a machine learning approach to reveal a high- density processing regime previously dismissed due to concerns about material instability. With targeted adjustments, the scientists unlocked new ways to process Ti-6Al-4V. “This isn’t just about manufacturing parts more quickly,” says Croom. “It’s about striking the right balance among strength, flexibility, and efficiency. AI is helping us explore processing regions we wouldn’t have considered on our own.” jhuapl.edu. Image generated by DDG DaVinci2 model with prompt from Nicolas Posunko/Skoltech.
ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 1 1 PROCESS TECHNOLOGY NEW METHOD MAKES ALUMINUM TRANSPARENT Researchers at Ateneo de Manila University in the Philippines are exploring new ways to make transparent aluminum oxide (TAlOx) because current methods are expensive and complicated, requiring high-powered lasers, vacuum chambers, or large acid vats. TAlOx is extremely hard and scratch-resistant, so it is often used as a protective coating on electronics, optical sensors, and solar panels. Instead of immersing sheets of metal into acidic solutions, the scientists and that is not something you can physically see—you kind of infer it based on how it interacts with its neighbors or how it interacts in its environment,” says researcher Paul Chiarot. “With electrospray, the material it spits out has a high electric charge, and that charge accumulates on the surface as the material is depositing. Measuring the accumulation and decay of that charge is very difficult to do experimentally.” A $517,969 grant from the National Science Foundation will bring together faculty from Binghamton and the University at Buffalo to integrate experiments, computational modeling, and machine learning methods to develop a comprehensive framework for the electrospray deposition process. Current use of electrospray deposition involves what Chiarot jokingly calls a “shakeand-bake process” to narrow down results until an optimal product is produced. “Right now, we have to do some trial and error to get the ideal characteristics for the film,” he explains. “We’d like to use the AI tools and modeling to know exactly how we need to operate our process to achieve those desirable characteristics.” If successful, Chiarot believes the models could be used for more than electrospray. binghamton.edu. placed microdroplets of an acidic solution onto small aluminum surfaces and applied an electric current. Just two volts of electricity was all that was needed to transform the metal into glass-like TAlOx. This droplet-scale anodization pro- cess is simpler than existing methods and also more environmentally friendly. The technique relies on electrowetting in which an electric field changes the properties of a liquid droplet, allowing precise control over the anodization process. The new approach could make TAlOx cheaper and more accessible for applications in everything from touchscreens and lenses to highly durable coatings for vehicles and buildings. The researchers say it could also lead to advances in miniaturized electronics, as scientists now have a way to convert metal surfaces into insulating and transparent layers on a microscopic scale. ateneo.edu. MAKING MICROSCOPICALLY THIN FILMS Researchers at Binghamton University, New York, are trying to perfect the low-cost method of electrospray deposition to make microscopically thin polymer films. They say the process could have applications in everything from electronics manufacturing to healthcare, for example by eliminating corrosion in mobile phone components or preventing bacterial buildup on medical implants. However, one obstacle limiting the adoption of electrospray is the difficulty in consistently applying it to the required specifications. Studying the process at a microscopic scale is also difficult. “The role of electric charge in the process is really important, A research team led by City University of Hong Kong is building on their work on the first-ever supranano magnesium alloy, showing how supranano engineering can lead to higher strength and ductility in bulk structural materials. doi.org/10.1126/ science.adr4917. BRIEF Transparent aluminum oxide was made by researchers in their lab in the Philippines. Courtesy of Budlayan et al., 2025. Microscopic view of a polyimide coating applied with electrospray deposition on bond wire used in electronics packaging. Courtesy of Binghamton University.
ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 12 EMERGING TECHNOLOGY NEW TOOL ANALYZES NANOPLASTICS An international team led by the University of Massachusetts Amherst developed a tool called OM-SERS (optical manipulation and surface-enhanced Raman scattering) to quantify the concentration of nanoplastics in a given sample, as well as detect the specific plastic types within it. The scientists say the tool can be used to detect nanoplastic concentrations and polymer types in samples such as soils, body tissues, and plants. “Because nanoplastics are so tiny, they have a much higher overall surface area and functional groups than microplastics, which means more of them can concentrate in water, soil, and body tissues,” says researcher Baoshan Xing. “They travel more easily and can wind up in more places in the environment and in our bodies. And once in those places, they are more reactive and the chemicals and additives in them can more easily leach out into their surroundings.” OM-SERS involves lasers, gold, and water. The researchers say it is the fastest, most efficient, and most reliable method yet developed to measure and analyze nanoplastics. OM-SERS begins with a water sample of just a few milliliters, into which the scientists place gold nanoparticles. Next, they shoot the nanoparticles with a laser and as the particles heat up, they attract the nanoplastics floating freely in the sample. Once the nanoplastic particles have flocked to the gold stack, the team rinses the sample with pure water, which flushes out the salts and any non-plastic debris. Left behind are tiny plastic particles gathered around a gold center, which may then be further analyzed. umass.edu. LIGHTSAILS FOR INTERSTELLAR TRAVEL Researchers from Brown University, Providence, R.I., and Delft University of Technology (TU Delft) in the Netherlands, developed a new way to design and fabricate ultrathin, ultra-reflective membranes for lightsails. In their new study, the team describes a lightsail membrane that is 60 mm wide by 60 mm long, but with a thickness of just 200 nm. The surface is patterned with billions of nanoscale holes, which help to reduce weight and increase reflectivity, giving the material more acceleration potential. Lightsails have the capacity to reduce flight time to nearby stars from several thousand years using current propulsion systems to just a decade or two. “The...fabrication process is scalable to the dimensions needed for interstellar travel and can be done in a cost-effective manner,” says Miguel Bessa, associate professor in Brown’s School of Engineering. The research is a big step toward realizing goals like those of the Starshot Breakthrough Initiative, founded by Yuri Milner and Stephen Hawking. The goal is to use ground-based lasers to power hundreds of meter-scale lightsails carrying microchip-sized spacecraft. For their design, the team used single-layer silicon nitride. The optimization process involved designing a pattern of nanoscale holes, billions of them across the material’s surface with diameters smaller than the wavelength of light. The scientists developed a new artificial intelligence method to adjust the shape and placement of holes. Once they arrived at the best design, the TU Delft team began fabricating it in the lab. Producing this lightsail with traditional methods would have been extremely pricey and taken as long as 15 years. With the new techniques, fabrication took a day and is thousands of times less expensive. brown.edu. Kraken Robotics Inc., Canada, acquired 3D at Depth Inc., Houston, a subsea services company specializing in high-resolution LiDAR imaging and measurements. The purchase complements Kraken’s suite of synthetic aperture sonar and sub-bottom imaging technologies. krakenrobotics.com. BRIEF The gold nanoparticle stack (GNS) is shown on left and nanoplastics on right. Courtesy of UMass Amherst. To obtain a sample’s reflectivity spectrum, a nanowafer with a suspended photonic crystal membrane is clamped in the measurement setup. Courtesy of TU Delft and Brown University.
ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 13 13 JACQUET-LUCAS AWARD This entry won the prestigious 2024 JacquetLucas Award for Excellence in Metallography at the International Metallographic Contest held during IMAT in Cleveland, October 2024. SCALE-BRIDGING CHARACTERIZATION OF ACICULAR FERRITE NUCLEATION Adrian Herges, Christoph Pauly, and Frank Mücklich, FASM* Department of Materials Science Saarland University, Saarbrücken, Germany Sebastian Scholl Aktien-Gesellschaft der Dillinger Hüttenwerke Dillingen, Germany *Member of ASM International
ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 14 Monopiles are a crucial component of wind turbines in offshore power plants, serving as the foundation for these structures. Fabricated from heavy steel plates welded together, these structures are built to withstand cold, oceanic environments with a minimum service life of 20 years. Hence, the mechanical properties and crack-resistance are of utmost importance to guarantee sufficient product properties[1]. Electron beam welding, a technique investigated in this study as an alternative to submerged arc welding, has seen limited industrial application in monopile construction to date, primarily due to concerns regarding the fracture toughness of the resulting material and the vacuum conditions required for welding. Due to the necessity to weld the steel plates for monopile construction, thermal influence is generated on the microstructure of the base material, which can generally worsen the mechanical properties, particularly the fracture toughness[2]. Thus, a tough microstructure must be generated to guarantee high crack resistance. Acicular ferrite as a microstructure constituent is well established as a crack-resistant phase promoting the fracture toughness and strength of welds[3]. Its formation is based around particles as nucleation sites, which necessitate an adapted chemical alloy composition to facilitate suitable particle nucleation as not all particles are as likely to nucleate acicular ferrite, for example in the case of vanadium nitride and vanadium carbide[4]. To better understand the formation of acicular ferrite, an investigation of acicular ferrite nucleation sites in electron beam welding was performed and a suitable approach for the evaluation of acicular ferrite is proposed. This characterization was performed as a scale-bridging approach, to facilitate the macroscopic assessment of the present phase and combine it with higher resolution imaging and information. Scale-bridging in this context refers to the use of measurements that span multiple orders of magnitude, which is then correlated. Once the nucleation site is identified, the particle of interest can be investigated. Here both chemical information as well as crystallographic information were obtained, further enabling a nanoscopic analysis using a transmission electron microscope and a scanning transmission electron microscope. EXPERIMENTAL PROCEDURES The material investigated was a low-alloyed steel of the type S355 ML. Steel plates with a thickness of 8 cm were used for the study, which were welded using electron-beam welding with a nickel foil of 0.1 mm thickness in a horizontal position. Then samples were sectioned and manually ground using P80, P180, P360, P600, and P1200 grit papers. Subsequently, electro- polishing was carried out using A2 electrolyte with the LectroPol-5 system by Struers for contrasting. These preparation steps enabled observations with the light microscope and various electron microscopy techniques. The laser-scanning microscope of the type OLS4100 by Olympus, was operated in optical mode to obtain light microscope images of the investigated area. An overview of the selected parameters for the electron microscopy techniques and their abbreviations are provided in Table 1. TABLE 1 — ELECTRON MICROSCOPY TECHNIQUES, ABBREVIATIONS, AND PARAMETERS EMPLOYED IN THIS STUDY Microscopy technique Abbreviation Parameters Scanning electron microscopy SEM 5 kV Backscatter electron detector BSE 5 kV Energy dispersive x-ray spectroscopy EDS 10 kV Electron backscatter diffraction EBSD 20 kV, 0.3 µm Scanning transmission electron microscopy STEM 30 kV Transmission Kikuchi diffraction TKD 30 kV, 0.015 µm Transmission electron microscopy TEM 200 kV SEM and BSE images as well as EBSD measurements were taken using a Helios G4 PFIB CXe, while STEM and TKD analyses were performed with a FEI Helios Nanolab600 Ga-FIB/REM. Additionally, a TEM Jeol F200 was used to acquire TEM images. The evaluations of EBSD measurements were conducted with the program EDAX OIM Analysis 8, and EDS evaluations were attained using APEX EDX (2.5.1001.0001). TEM results, especially selected area diffraction patterns (SAED patterns), were furthermore evaluated using the program SingleCrystal version 5.1 and prior by CrystalMaker Software Ltd[5]. RESULTS AND DISCUSSION Figure 1a showcases an electron beam weld seam within the steel with its melt zone highlighted within blue lines as well as its heat affected zone highlighted in black. The contrasted microstructure obtained by performing an experimental routine is illustrated in Fig. 1b and was found in the melt zone. The characteristic microstructure of acicular ferrite, namely the laths radiating from a central particle, is revealed in Fig. 1b. The observed laths are elongated in three different growth directions to around 50 µm each and a thickness of about 10 µm, resulting
ADVANCED MATERIALS & PROCESSES | MAY/JUNE 2025 15 Fig. 1 — (a) Digital camera image of the weld seam within the material and (b) light microscope image showing a particle embedded within acicular ferrite laths in the melt zone, highlighted with an orange arrow. The laths appear to originate from the particle, indicating a potential nucleation site. in six mostly visible laths, highlighted with black arrows. The identified region was then marked and documented. Further observations were subsequently performed using electron microscopy techniques as shown in Fig. 2. First, using the SEM it was confirmed that the particle seemed to be embedded within the matrix. Afterwards, EBSD analysis was performed to confirm the existence of acicular ferrite in the particle’s vicinity resulting in Figs. 2a and 2b. For this purpose, misorientation angles were then obtained and compared to literature values according to a method proposed by Gourgues et al., which allowed a clear differentiation between acicular ferrite, which is generally characterized by an absence of lowangle misorientation boundaries and a high proportion of misorientation angles around the NW/NW orientation relationship, and other possible microstructure constituents like upper bainite[6]. The misorientation angles shown in Fig. 2c confirmed the acicular ferrite microstructure, exhibiting a small occurrence of low-angle misorientation angles. The increase in the proportion of misorientation angles around 30° and above has also been observed in other studies[7]. However, at this stage no definitive explanation can be provided for these data points. Due to the particle’s unique (a) configuration, which was supposedly split in half with its midsurface facing upward, EDS measurements could be performed without significant topographic distortions. The results of these measurements are shown in Fig. 3. (b) Fig. 2 — (a) SEM image illustrates the particle, highlighted by an orange circle, within the steel matrix; and additional EBSD image showing the di erent lath orientations as cubes around the particle. The surrounding region is shown in part (b) with the previously shown region in part (a) in the black square. The misorientation angles measured within region (b) are shown in (c). A direct comparison with data adapted from Gourgues et al.[6] emphasizes the acicular ferrite phase structure, with a small proportion of low-angle misorientation angles. A more narrowly defined region also confirmed this finding. (a) (b) (c)
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