Additive Manufacturing is Reshaping Modern Manufacturing

Summary

A transformative force that’s reshaping the landscape of production and design has emerged in modern manufacturing and its push toward Industry 4.0. Additive manufacturing—also called three-dimensional (3-D) printing—is where digital precision converges with material innovation to construct objects layer by layer. Unlike traditional subtractive methods—namely, machining—that carve away from a solid block of metal, plastic or other material, 3-D printing builds objects from the ground up. This offers flexibility in creating intricate geometries and optimized parts, while reducing waste and material costs (Figure 1). 

The process of 3-D printing an object begins with a digital blueprint, a design crafted using computer-aided design (CAD) software. This digital blueprint is then sliced into thin cross-sectional layers that guides the 3-D printer in understanding the object’s geometry. With precision, the printer adds layers of material until the final product emerges (Figure 2). Post-processing steps such as cleaning, polishing or painting are typically performed to achieve the desired finish. 

Adopting 3-D printing propels industries into the era of Industry 4.0, fostering agility and adaptability. This technology enables on-demand production of customized products without the need for costly retooling and production delays, offering a rapid response to evolving market demands. The benefits extend beyond customization; 3-D printing accelerates product development cycles through rapid prototyping, supporting decentralized manufacturing and minimizing supply chain disruptions. 

By integrating 3-D printing with other Industry 4.0 technologies, organizations can enhance their adaptability and responsiveness. The fusion of 3-D printing with technologies like the Internet of Things (IoT), artificial intelligence (AI), machine learning (ML), digital twin technology, cloud computing, and blockchain amplifies its impact, fostering innovation and efficiency across diverse sectors. 

Applications for 3-D printing reach across several industries: 

• Health care: Personalized prosthetics, dental implants, and even bioprinting tissues for research or potential transplants. 
• Aerospace and defense: Crafting lightweight yet durable components and intricate shapes with on-demand part printing. 
• Automotive: Rapid prototyping and, in some cases, end-use part production for custom or high-performance vehicles. 
• Construction: Large-scale 3-D printers are fabricating building components and structures, revolutionizing construction timelines. 

Additive manufacturing methods 

Additive manufacturing/3-D printing encompasses a range of technologies such as digital light processing (DLP), fused deposition modeling (FDM), selective laser melting (SLM), and electron beam melting (EBM), each with its unique advantages. Choosing the right technology depends on factors like product requirements, materials, and costs, posing a challenge in finding the perfect fit for modern manufacturing. These methodologies vary in terms of their working principles, materials, and applications, allowing a diverse range of 3-D printing capabilities across different industries and use cases. 

DLP uses a digital light projector to cure liquid photopolymer resin layer by layer. The process typically offers high resolution, making it suitable for detailed and intricate models. Materials are limited to photopolymer resins that can be cured by light. DLP is commonly used in industries requiring high precision and detail such as jewelry, dental, and prototyping. 

The FDM process involves extruding thermoplastic filaments layer by layer through a heated nozzle. The layer resolution is typically lower than that of DLP, making it suitable for general-purpose printing. This process uses a wide range of thermoplastic materials like polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), polyethylene terephthalate glycol (PETG), thermoplastic polyurethane (TPU), and composite materials. FDM is versatile and widely used for prototyping, functional parts, and hobbyist projects. 

The SLM process uses a high-powered laser to selectively melt and fuse metal powders layer by layer. It offers high resolution and precision in metal printing. Commonly used materials include metal powders like titanium, aluminum, and stainless steel. The SLM process is widely used in aerospace, health care, and automotive industries for producing complex metal components. 

The EBM process is like SLM except EBM uses an electron beam instead of a laser to melt and fuse metal powders. Its layer resolution is comparable to SLM, providing high resolution for metal printing. This process uses metal powders like titanium, cobalt-chrome, and nickel alloys. EBM is commonly used in aerospace and medical industries for manufacturing high-strength metal parts. 

Trends in 3-D printing  

The 3-D printing industry is experiencing significant growth and showcases trends such as compact modular systems, a surge in metal 3-D printing, streamlined workflows, advances in materials, and improving economics for manufacturing. In North America, the additive manufacturing market, valued at $3.7 billion in 2021, is set to grow at a staggering CAGR of 19.8% from 2022 to 2030. Global venture capital investments in additive manufacturing companies reflect a robust growth trajectory, with a focus on specialized product-market fit opportunities and an increase in product customization on demand. 

Globally, North America is leading with more than 34.1% revenue share, driven by developed economies and early technology adoption. Europe is following closely with strong technological expertise in additive manufacturing. The Asia Pacific region is poised for significant growth with the highest CAGR, driven by manufacturing developments and urbanization. 

Broken down by common printer types, industrial 3-D printers had a respectable revenue share of more than 64% in 2021. These printers find applications in prototyping, designing, and tooling across various industries. Originally for hobbyists, desktop 3-D printers are gaining traction in household, education, and small business settings.

Stereolithography (SLA) had more than 9% revenue share in 2021. FDM, direct metal laser sintering (DMLS), selective laser sintering (SLS), inkjet printing, PolyJet printing, DLP, and EBM are gaining traction. Prototyping has more than 56% revenue share; 3-D printing for prototyping is widely used in automotive, aerospace, and defense industries. 

Key 3-D printing advantages 

Advantages of 3-D printing include flexibility and customization, speed and efficiency, cost reduction, sustainability, supply chain simplification, and more. 

Flexibility and customization: 3-D printing allows the creation of custom and complex geometries, bringing in the era of mass customization tailored to individual needs. It allows the use of various substrates from metal, plastics, and resin-based materials to fit many use case applications.  

Speed and efficiency: Directly translating digital designs into final products, 3-D printing reduces lead times and promotes rapid prototyping for swift design iterations. 

Cost reduction: Eliminating the need for expensive tooling, 3-D printing is cost-effective for low-volume production, where traditional methods might be economically impractical. It yields higher quality results with precision.  

Sustainability: The additive nature of 3-D printing results in less waste compared to subtractive methods, contributing to increased sustainability. Decreasing the use of electricity, plant floor space, and minimal chemical production helps with a company’s initiatives of near net-zero emissions. 

Supply chain simplification: On-demand manufacturing reduces the need for extensive inventories, streamlining the supply chain and minimizing transport costs and delays. 

Guidance for automation professionals 

In the dynamic field of 3-D printing, adherence to industry standards is vital. Leveraging standards from ASTM International, ISO/ASTM 52900:2015, FDA guidance, NIST AM standards, and VDI 3405 ensures consistent, safe, and high-quality practices. 

For automation professionals delving into 3-D printing, a comprehensive understanding of technology, materials, CAD/CAM, process optimization, quality control, automation integration, and safety considerations is crucial. This knowledge empowers professionals to harness the potential of 3-D printing, integrating it seamlessly into their projects and driving innovation in the realm of automation. 

As 3-D printing continues to reshape industries and redefine manufacturing possibilities, staying informed about the latest trends, market dynamics, and best practices is essential for professionals navigating this transformative landscape. 

_{This feature originally appeared in the March edition of AUTOMATION 2024: IIoT and Digital Transformation.}