New Materials, Smarter Tools for Additive Manufacturing

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Forget simple prototypes and plastic toys. Today's additive manufacturing technologies are building rocket engines, restoring ancient artifacts, and printing human tissue in space.
What began with simple clay structures thousands of years ago has evolved into artificial intelligence (AI)-powered, precision-controlled systems that have the potential to change how we design and produce almost everything.

 Agility, fast turnaround, material efficiency, and reduced need for retooling have made 3D printing increasingly attractive in recent years. As global supply chains face continued pressure from factors like geopolitical changes and material shortages, additive manufacturing offers a way to localize production, reduce lead times, and respond faster to changing demands.  For example, companies can produce and deliver parts locally, enabling faster turnaround times and improved customer satisfaction. New software, materials, and methods, plus advancements in AI and machine learning (ML), are further advancing the capabilities of modern additive manufacturing.

This article highlights a brief history of additive manufacturing and the emergence of 3D printing. It will also discuss several modern 3D printing technologies and introduce a few innovative and new technologies in development.

Foundations of Additive Manufacturing 

Additive manufacturing has humble prehistoric origins, with early examples like pottery, mud-brick buildings, stonework, metalwork, and glasswork. These crafts used heat, moisture, and simple chemical reactions to combine materials manually, layer by layer—much like today's processes, but without the machines. Later, materials like fiberglass and techniques like multi-part injection molding, multi-material casting, and welding (Figure 1) advanced the concept and led to more scalable production methods.
 Figure 1: A welder performing gas tungsten arc welding (GTAW) or tungsten inert gas (TIG) welding. (Source: NASA)

In electronics, additive principles found new applications through sheet lamination for circuit boards and precision material deposition in semiconductor manufacturing.

These techniques laid the groundwork, but the past few decades have pushed us into a new era where automation, robotics, and digital tools play a role. This has led to what we now call 3D printing, an additive manufacturing method where parts are produced layer by layer quickly and precisely, at levels of complexity that traditional manufacturing is having trouble matching.  

Modern Additive Manufacturing

Progress in automation and robotics has enabled advancements in established methods of additive manufacturing, such as welding. But it wasn't until the past couple of decades that significant advancements in additive manufacturing of metals, ceramics, and plastics emerged. These advancements and the rise of robotic systems led to the range of 3D printing methods used today.

The process of 3D printing has become uniquely powerful in the world of manufacturing because it converts a 3D model of an object into a series of machine instructions for a computer numerical control (CNC) machine. The machine uses these instructions to gradually deposit or build material, creating an object. In some cases, 3D printing may require post-processing to complete the part, such as sintering (for some ceramics or metals), ultraviolet (UV) curing (for resin-based systems), or possibly some cleanup process procedures. 

Today, many 3D printing technologies are used in homes, labs, and factories. Each of the following common methods has strengths that cater to the material, speed, or application:

•  Fused filament fabrication (FFF, also called fused deposition modeling (FDM)): Melted plastic is extruded through a nozzle to build parts layer by layer. This method provides an accessible and affordable option for prototyping and small runs.
• Stereolithography (SLA) and digital light processing (DLP): UV light hardens liquid resin into solid parts. These processes are known for high resolution and smooth surfaces.
•  Selective laser sintering (SLS) and selective laser melting (SLM): Lasers fuse powdered materials, such as plastics or metals, layer by layer. This process is common in industrial applications where strength and detail are important.
• Binder jetting: A binding agent is sprayed onto a powder bed to form parts. This method is often used for the large-scale production of metal and ceramic parts.
• Volumetric additive manufacturing (VAM): Volumetric light patterns are applied to a light-sensitive resin to build multiple parts simultaneously. This method is faster than layer-by-layer and does not require support structures. 
• Liquid metal jetting (LMJ): Jets of molten metal create parts without powders or build plates. This is an emerging process with the potential to reduce costs and complexity.
• Ultrasonic additive manufacturing (UAM): Ultrasonic vibrations bond metal layers. This method is useful for combining different metals and is valuable in aerospace applications.
• Two-photon polymerization (2PP): Precise laser energy solidifies resin at the nanoscale. 2PP is used for microstructures and biomedical devices.
• 3D bioprinting: Deposited layers of biological material or bio-inks create tissue-like structures. This process is common in regenerative medicine research.

Additionally, the following categories collectively refer to multiple methods:

•  Powder bed fusion: This is an umbrella term for laser-based methods (like SLS and SLM) that fuse powdered materials.
• Vat polymerization: This is an umbrella term for methods like SLA and DLP, where light cures resin in a vat to create parts. 

Newer approaches, like VAM, LMJ, and 2PP, emerged to overcome earlier limitations by either increasing speed, reducing post-processing, or pushing resolution levels. Each expands the possibilities of what can be printed, and how.

3D printing has fascinated manufacturing professionals of every scale, along with hobbyists, customers, and startups. The early benefits and appeal of 3D printing popularized technologies like FDM and SLA, followed by industrial solutions like SLS. The ubiquity of 3D printing has transformed into more investment and development of surrounding technologies, and this exploration has resulted in many new 3D printing technologies and materials.

What's Next for Additive Manufacturing?

As additive manufacturing continues to mature, the industry is examining what 3D printing can really achieve, such as smarter designs, new materials, and biofabrication breakthroughs. 

Materials Inspired by Nature

Biomimicry is a design approach guiding the development of printable structures that mimic natural structures like bone or coral, offering strength and lightness in one design. Sustainable materials, such as wood, natural fibers, and minerals, are being tested to reduce the environmental impact of 3D printing and even to replace ivory in artifact restoration.  Mycelium, a part of fungi, is also being explored as a "grown" 3D printed material to replace concrete and other less sustainable building materials. 

Researchers are also developing ways to turn waste into usable polymers or composites, reducing landfill impact while keeping useful structural properties. In food and biofabrication, methods for 3D printing chocolate, sugar, synthetic animal proteins, actual animal proteins, and even synthetic human organ replacements have been developed.

Smarter Software and AI/ML Optimization

Many software tools are now available to simulate the 3D printing process and help users improve reliability, consistency, and efficiency before printing even begins. These tools can predict how a part might deform or fail, reducing waste and speeding up design. Some software takes it a step further, using AI and ML to fully automate parameter tuning and lessen the need for operator input. 

Electrospinning and Biofabrication

Electrospinning is a process that uses electric fields to produce very fine fibers from liquid polymers. In the medical field, electrospinning is being combined with 3D bioprinting to create nanofiber scaffolds that support tissue regeneration.  These delicate structures are compatible with living tissue and can support cell growth, enabling new treatments in wound healing, regenerative medicine, and drug delivery. Figure 2 shows one example of this innovation, as a human knee meniscus is 3D printed in orbit aboard the International Space Station.

 Figure 2: A human knee meniscus 3D printed in orbit using the BioFabrication Facility. (Source: NASA) 

Hybrid Manufacturing and Metal Expansion

Substantial leaps in metallurgy have occurred over the past two decades to develop various metal powders optimized for 3D printing technologies, expanding options for strength, thermal stability, and printability. One method, Directed Energy Deposition (DED), differs from extrusion-based printing by using lasers, plasma arcs, or electron beams to melt and deposit metal directly, enabling precise repairs or multi-stage builds.

DED can also add material to existing parts, making it ideal for hybrid manufacturing workflows that combine additive and subtractive techniques. Methods like DED and UAM also allow for the joining of dissimilar metals, which is critical in aerospace and high-performance environments where components must withstand extreme conditions.  DED is much like FFM and other material-deposition methods, except that instead of heating a material within a nozzle or using curable materials or materials that self-set, DED uses lasers, plasma arcs, electron beams, or other directed energy sources to melt or fuse material that is being fed or deposited into the targeted zone. 

Since DED and UAM can also add material to existing components or join dissimilar metals, they are ideal for multi-stage builds, part repairs, and high-performance applications in aerospace or extreme environments.

Together, these advances are transforming 3D printing from a prototyping tool into a smarter and more adaptive manufacturing platform that is better suited to meet modern production demands. Initiatives like NASA's Rapid Analysis and Manufacturing Propulsion Technology (RAMPT) project (Figure 3) highlight the increasing pace of additive manufacturing innovation and its growing role in the future of high-performance engineering.

 
Figure 3: A chart of additive manufacturing milestones led by the NASA RAMPT project. (Source: NASA) 

Conclusion

Additive manufacturing is a historically powerful method of producing parts and structures on the scale of massive buildings to minute biomedical implants. With smarter tools, better materials, and emerging processes like hybrid metal repair, nanofiber biofabrication, and AI-driven optimization, 3D printing is evolving into a critical part of the modern manufacturing landscape.

Its ability to reduce waste, speed up design iteration, and facilitate complex or localized production is reshaping how industries such as aerospace and healthcare approach product development.

While challenges remain, the innovations explored in this article show that additive manufacturing is steadily transitioning from experimental to a crucial part of the new solutions springing up to meet today's demands and tomorrow's possibilities.

  ¹https://3dprint.com/317017/strategic-advantage-of-3d-printing-in-a-time-of-import-tariffs/
  ²https://www.alphaprecisionpm.com/blog/advantages-of-additive-manufacturing-over-conventional-manufacturing
  ³https://www.sciencedirect.com/science/article/pii/S2214860424001404
 ⁴https://additec3d.com/what-is-liquid-metal-jetting
  ⁵https://ceramics.org/ceramic-tech-today/3d-printed-material-offers-elephant-friendly-alternative-for-restoring-ivory-artifacts/
  ⁶https://doi.org/10.1155/2022/8401528
  ⁷https://3dprintingindustry.com/news/ai-build-launches-new-version-of-its-ai-powered-3d-printing-software-231103/
  ⁸https://www.sciencedirect.com/science/article/abs/pii/S2772950822004125
  ⁹https://www.sciencedirect.com/science/article/pii/S2238785424015862