Additive Manufacturing (AM) is receiving lots of hype these days, as seen in the frequency of articles, social media posts, and online searches, plus high growth rates, massive private and public investments, and soaring company valuations—and deservedly so. It is not every day that a manufacturing technique comes along which not only changes how parts are made but how they can be redesigned or reimagined for dramatic improvements in performance. Supply chains are being reconsidered in light of the possibility of “digital inventory” and “mass customization”. And, significantly, AM can be applied across a huge range of materials, i.e., polymers, metals, ceramics, composites, concrete, organic tissue, as well as sizes from microns to meters.

In the world of industrial manufacturing, early growth came with polymer-based AM (or 3D printing as many call it) as engineers used the technology for 3D printing prototype parts. As software becomes more sophisticated and systems more user-friendly, polymer 3D printing exploded. While useful, these printers produce relatively low-value components.

 On the heels of the successful introduction of polymer-based AM, engineers and scientists began developing metal-based AM processes to produce not only prototypes but also functional components of significantly higher value than polymer. According to the AMPOWER Report 2021, the polymer AM market is 2.5x larger than metal though metal is growing faster with an expected CAGR of just under 30 percent in the next 5 years. The lion’s share of metal AM growth is due to powder bed fusion as well as sintering-based technologies such as binder jet and fused deposition modeling.

"Software advancements will lead to improved prediction of residual stresses and mechanical properties"

For manufacturers looking to incorporate metal AM for large-format applications, i.e., components that measure several feet or more with weights in the hundreds, if not thousands, of pounds, there are alternative AM technologies that are quickly establishing themselves as reliable and cost-effective. Wire-based AM technologies such as arc welding, laser, and electron beam can be used by manufacturers now to produce not just prototypes, but tooling, replacement parts, and in-service components using well-established welding alloys and processes that have been used for decades in critical applications. Manufacturers can take advantage of lower lead times, less material waste, improved part performance, and enhanced designs afforded by AM.

The database of mechanical properties is growing as well as industry codes and standards, which should increase confidence in the technologies. For example, ASME’s Boiler and Pressure Vessel Code has been a trusted global standard for over 100 years. ASME’s Section IX committee, which oversees welding, recently approved a code case for manufacturers to qualify procedures for gas metal arc AM. Others such as the American Welding Society and DNV have also developed metal AM standards with others also in the works. With ASME and other standards bodies developing codes and specifications in coming years, manufactures can confidently adopt large-format metal AM.

Further driving adoption is the rapid development of the technology:  software capabilities, facility efficiencies, and process improvements, all of which improve quality and reduce costs. Software advancements will lead to improved prediction residual stresses and mechanical properties. As more factories install systems, manufacturing efficiencies and quality will increase dramatically. Process development will continue to improve not only reliability but also costs. For example, Oak Ridge National Laboratory in conjunction with Lincoln Electric recently demonstrated a 3x improvement in deposition rates by utilizing 3 robot arms simultaneously.

 AM is not a panacea and it will not take over manufacturing wholesale. What it does provide is a powerful tool in the manufacturer’s tool belt that opens up new worlds of possibilities in speed to market, part performance, or designs, and manufacturers can start using AM now for their large-format applications