Engineers Week – an event first celebrated in 1951 by the National Society of Professional Engineers – ran from February 20-26, 2022. The theme for this year’s event was “Reimagining the Possible”, which highlights how engineers make a difference in the world.
The goal was to engage children in engineering and STEM topics and activities. To mark the occasion, this article discusses the significant impact of materials science engineers and describes some of the most recent advances in the field.
Materials Science Underlies Pretty Much Everything
The universe does not simply divide into clearly defined silos. Thus, the field of materials science includes a wide range of applications, from crystal structures essential to semiconductors to titanium alloys, from breakthroughs in nanotechnology to the development of sustainable bioplastics, and from metallenses to color-tunable LEDs. This may interest you : CGTN: Hong Kong on the highway to become a global technology and innovation hub in 25 years. Materials science has helped shape the modern world.
This interdisciplinary field – also known as “materials science and engineering” – combines elements of chemistry and physics and focuses on the design and discovery of new materials (especially solids). He has been described as “using the periodic table as his grocery store and the laws of physics as his cookbook.”1
One of the earliest examples of materials science – long before the term was known – was the manufacture of bronze around 3,500 years ago. Composed of copper and lead, this metal alloy is stronger than copper, allowing Bronze Age craftsmen to hammer and melt it into practical tools and objects and contribute to the development of human civilization.
Examples of materials science from different eras: Bronze Age ax head (left) and ultra-thin achromatic “mesh” metalene recently developed at UC Berkeley (right, scale bar represents 5 micrometers ). Image Credit: Radiant Vision Systems
The Foundation of Information Technology
Modern materials science actually helped create the computer and consumer electronics industry. It all started with the development of an ultra-pure form of silicon (now called electronic-grade silicon) that is made by removing impurities such as boron, phosphorus and carbon. Read also : Why do some distrust science and what can scientists do about it?. To produce integrated circuits, silicon must contain <0.1 parts per trillion of these materials.
Between 1955 and 1990, improvements and innovations in semiconductors “raised the performance and lowered the cost of electronic materials and devices by a factor of a million – an unprecedented achievement in the history of human technology. . »2
To put that into perspective, Omkaram Nalamasu, CTO of Applied Materials, explains, “To build today’s smartphone in the 1980s would cost around $110 million, require nearly 200 kilowatts of power ( compared to 2 kW per year today), and the device would be 14 meters high.3
Today, telecommunications infrastructure and systems depend on “various crystalline semiconductors; metallized film conductors; dielectric films; welds; ceramics and polymers formed into substrates on which circuits are assembled or printed; and gold or copper wiring and wiring. »4
The base material of a significant number of LEDs and display devices is indium gallium nitride (InGaN) – a manufactured mixture of gallium nitride and indium nitride. When transformed into crystals, InGaN aids in tuning the bandgap needed to emit light through the infrared, visible, and ultraviolet spectra.
A blue LED, made possible by the indium gallium nitride alloy. Image Credit: Radiant Vision Systems
Materials scientists persist in their search for new, smart materials with properties not typically found in nature. For example, graphene is a two-dimensional version of diamond or graphite, a layer of carbon one atom thick in a hexagonal lattice structure.
Graphene is a remarkable material because “it is 200 times stronger than steel by weight. Over the past 10 years we have been able to use graphene to make new types of electronics, very high performance transistors, new types of sensors and new types of composites based on its unique properties.
A flexible and transparent graphene sheet in the laboratory. Image Credit: Radiant Vision Systems
Recent Materials Science Advancements
Next, we present a number of examples of emerging applications and recent technological innovations where materials science has played a key role. To see also : What We Miss When We Don’t Reframe the History of Science.
Safer than Lithium Batteries
Lithium-ion batteries are the primary power source for most electronic devices and vehicles today. However, they have two major drawbacks: first, they contain a liquid electrolyte that can be extremely flammable, and second, the global lithium supply chain can lead to increased geopolitical tensions.
Recently, a group of researchers from the University of Geneva developed a solid electrolyte material that exhibits the conductive properties required for batteries. The material (carbo-hydridoborate) is produced from sodium, an element cheaper than lithium and available in abundance almost everywhere on earth.
“Frozen Smoke” aka Aerogels
A diverse group of porous materials, aerogels are considered the lightest solids in the world, composed of up to 99.98% air by volume and with unique special properties.
For example, “transparent super-insulating silica aerogels have the lowest thermal conductivity of any known solid. Super-high surface area carbon aerogels power today’s fast-charging supercapacitors. And ultra-strong, pliable x-aerogels are the lowest density structural materials ever developed. »6
Unlike garden gels, aerogels are dry and consist of the solid, low-density structure of a gel that remains after the moisture has been extracted.
NASA used silica-based aerogels for Mars rover insulation, and they were used as an absorbent in chemical spill cleanups.
Additionally, “Carbon aerogels are used in the construction of small double-layer electrochemical supercapacitors. Due to the large surface area of the airgel, these capacitors can be 2,000 to 5,000 times smaller than electrolytic capacitors of the same rating. Airgel supercapacitors can have very low impedance compared to normal supercapacitors and can sink/produce very high peak currents. »7
A block of silica airgel. (image source).
Folding Displays
LG Chem (sister company of LG Display) has created a new coverage window for foldable screen devices such as smartphones and laptops. Known as a “true folding window”, it is made by applying special coating materials to PET film (a type of thin plastic) to produce a surface as hard as glass but with the flexibility of plastic.
The material is intended to overcome device-related issues such as crease impressions or cracks at the hinged portion of a display. It also improves the blanket’s heat resistance and other mechanical properties.
Making the Impossible Possible
MIT engineers applied a new polymerization process to produce an entirely new material that is stronger than steel but lighter than plastic. It can be easily manufactured in very large quantities and has the potential to revolutionize the industrial landscape.
Uses include lightweight, durable coatings on everything from bridges and infrastructure to car parts and cell phones. In fact, a new form of plastic, polymer has the ability to self-assemble into 2D sheets – a process scientists thought was impossible, hence its nickname “impossible plastic”.
“Impossible” two-dimensional polymer film that is twice as strong as steel but as light as plastic. (image source)
This article lists some of the latest developments materials scientists and engineers are working on in laboratories and research facilities around the world. Amazing new substances are being developed every day with the potential to revolutionize medicine, technology and industry and help create a more sustainable planet.
References
This information has been extracted, revised and adapted from materials provided by Radiant Vision Systems.
For more information on this source, please visit Radiant Vision Systems.
