Materials Science has played a fundamental role in human history, so much so that historians have named entire time periods – Stone, Bronze, and Iron – after them. Each step forward in the evolution of Materials Science has heralded a transformational paradigm shift in technology, society and quality of life. This “evolution” in Materials Science was originally driven by trial and error: hitting certain rocks together yielded a sharp edge; carving pieces of wood or bone unlocked new uses; and heating ore produced precious metals. The process has grown more efficient over the ages, but the world of tomorrow can no longer rely on a history of happy accidents to unlock the next phase of technology and design.
The accelerating pace of innovation in today’s science-based industries has pushed the limits of Materials Science. Airplanes need to fly farther, faster; plastics require more varied and sustainable feedstocks; buildings must use less energy; and physicians want to manufacture heart valves on a patient-by-patient basis. While Materials Science has become more sophisticated than ever before, creating parts that are increasingly complex, small and precise, engineers can augment their research processes with the exciting capabilities offered by next-generation virtual tools. Virtual materials design allows the development of materials and structures that are customized to their environment or constructed at the site of deployment on a per-need basis. These predictive capabilities show us what is (and will be) feasible and viable, when and at what cost.
To realize the potential of such capabilities, scientists require the ability to explore the interactions of various material components from the quantum scale up through the macroscale. However, no single formula can predict every property across these temporal or spatial scales. The breakdown occurs at the mesoscale, where the line between quantum mechanics and Newtonian physics blurs. At this point small variations in the material’s structure become additive, providing the foundation for many of the unique materials seen in nature that engineers struggle to imitate. Multi-scale modeling provides the missing link between the quantum and macroscale. It builds models hierarchically, nesting the results of superfine simulations within continually coarser models. The application of these virtual predictive models, powered by multi-scale modeling, can produce transformative benefits for some of the key trends in current Materials Science:
- Nanomaterials – Designing materials at the nanometer scale unlocks unique properties unavailable to bulk materials. Scientists can isolate these “quantum-derived” properties by leveraging the additive properties of the mesoscale. For example, graphene, a repeating network of carbon molecules arranged in one-atom-thick sheets, possesses unique electrical properties making it ideal for batteries. At the same time graphene is also one of the strongest materials known. Multi-scale modeling enables scientists to explore the unique properties of nanomaterials, quickly and leanly identifying various formulations in silico to design materials with bespoke properties for each new application.
- Biomimicry – Nature has spent the past 4 billion years iteratively tweaking combinations of elements and structures to create materials with properties that rival and surpass the best we can make today. Consider bone, abalone shells, and spider silk; they have been optimized for lightweighting, fracture resistance, and strength, traits which are desired in a myriad of practical applications such as building materials, transportation and medical prosthetics. Amazingly, these materials can also be self-assembled at room temperature in aqueous solutions with little to no waste. Multi-scale modeling allows scientists to understand the molecular interactions and gradients of these materials, even to mimic the “green” manufacturing processes they utilize at scale.
- Smart Materials – While nature has engineered finely-tuned materials, it has also “programmed” systems of materials that react to their environment. The shape of a piece of wood will change with temperature, pH, gravity or electric or magnetic fields. These properties can be “tuned” to provide optimal functions across a variety of environments. Additionally, wood can also heal itself given time and basic inputs like water and CO2. Multi-scale modeling provides a unique window into this world of materials “systems,” often illuminating the fundamental processes that make them up.
Virtual materials design shows remarkable potential to ignite an engineering revolution, but engineers cannot take this leap until they unite virtual and real design. Fortunately, additive manufacturing (AM) provides a way forward. AM mimics the layer-based deposition of materials seen in many natural processes, producing hierarchical structures with gradients of properties and materials. While traditional additive techniques relied on the sequential curing of photoreactive resins or the deposition of hot plastics to build a part, advances in this space are unlocking new materials and methods that are catalyzing change. Constituent layers are becoming thinner, machine resolution and precision are improving, and build speed is increasing. Machines can alternate the materials they print with, to the point where parts can be designed with gradient materials and properties in mind. Engineers can now operate on the length and time scales needed to replicate the complex structures and materials seen in nature, and the future is only getting brighter.
Building this bridge between virtual and real design provides a unique way forward to the next age of Materials Science but it is important to acknowledge the importance of real-world testing. Models will continuously become more lifelike, but physical tests constitute the final step to creating a finished product. The true benefit of bridging virtual and real design is the ability to produce higher quality materials and parts faster than ever before. The bridge allows scientists to think outside the box while limiting the time and resource pressures faced by traditional R&D teams. As this distance between the virtual and real world shrinks, many innovators are realizing this benefit today.
This story is reprinted from material from Dassault Systèmes BIOVIA, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.