by Melissa Donovan
On demand spare parts production represents one of the most transformative applications of metal additive manufacturing (AM). Industries include aerospace, energy, oil and gas, maritime, mining, rail, and defense, which are already leveraging large format metal three-dimensional (3D) printing to reduce inventory costs, minimize downtime, and support aging equipment.
Above: Lasermeister is Nikon’s proprietary laser processing machine that uses the optical measurement and precision control technologies that Nikon has accumulated with semiconductor lithography systems. It enables various laser processing with high precision.
“Spare parts have become one of the clearest business cases of industrial metal AM because they address the problem of balancing inventory costs against operational risk,” notes Arvind Rangarajan, global head of product and strategy, HP Additive Manufacturing Solutions.
Worthy Application
On demand spare part production is one of the more important application uses of metal 3D printing—but this hasn’t always been the case.
“A few years ago, the focus was on proving that AM could produce end use metal parts. Today, the conversation has shifted to building reliable production models around those parts. That means creating digital inventories, establishing qualified manufacturing workflows, and producing components closer to the point of need—helping manufacturers strengthen supply chain resilience,” explains Rangarajan.
According to Dr. Behrang Poorganji, VP of technology, Nikon Advanced Manufacturing Inc., “on demand spare parts production addresses one of the most persistent challenges manufacturers face—maintaining equipment and systems when replacement components are difficult to source, expensive to inventory, or no longer in production. An added challenge for these older parts is that key reference documentation and schematics may no longer be available.”
“Equipment operating today in many industries was manufactured 20 to even 50 years ago, and the companies that made that equipment might no longer exist. Certainly the tools that made the parts have long been forgotten, and the skilled people that made them have long since retired,” adds Will Richardson, CEO,
Wayland Additive
Another point, according to Tyson Gregory, advanced manufacturing technologies sales, Nidec Machine Tool America, involves cost. “It is difficult for companies and the government to balance the cost of storing specialized or large parts long term or the extended lead times necessary to replace these parts.”
Maritime and defense organizations often require low volume and infrequent parts over a larger span of time, this is difficult for traditional manufacturing processes to support. On demand spare parts production addresses the challenges of cost and inventory, according Jonathan Buckley, senior AM applications engineer, JEOL USA, Inc., which makes it a critical application for metal 3D printing.
“Metal 3D printing enables these industries to hold digital inventories instead, allowing low-volume spare parts to be printed on demand. Because printing is not tied to a specific manufacturer or location, delivery times can be reduced even further. The ability to compress spare part delivery from months to days demonstrates the true economic value of 3D printing across the range of industries that need spare part production,” continues Buckley.
Other benefits to using metal AM for spare parts production, “is the removal of expensive tooling typically required to get spares produced. When it comes to on demand spares or aftermarket components, it’s typically related to supply chain problems such as outdated tooling, unavailable tooling, or vendors that have gone out of business. The ability to scan existing components, categorize them, and produce them on demand is a huge value add for critical industries that cannot afford equipment downtime,” explains Nate Harris, VP of sales NA, Mastrex.
“For many industries, it also provides a practical solution for legacy parts that are no longer supported by original suppliers or require expensive tooling to manufacture conventionally,” says Jenna Haggin, marketing communications specialist, EOS.
Beyond eliminating tooling, molds, and minimum order quantities, “AM enables redesign opportunities that can improve performance, reduce weight, consolidate assemblies, and extend service life. Manufacturers increasingly use AM to establish digital inventories that support more resilient and responsive spare parts supply chains,” admits Haggin.
“What’s becoming important is the production system around the technology. To manufacture spare parts at scale, organizations also need robust production workflows, validated materials, repeatable processes, and rigorous quality assurance. Digital inventories and software that enable qualified parts to be produced consistently across different locations are becoming just as critical as the printers themselves,” adds Rangarajan.
Benefiting from the Technology
On demand spare parts production via AM is advantageous for many industries.
According to Haggin, “those that operate complex, high-value assets and maintain extensive spare parts inventories, as well as industries with parts needed on demand with minimal lead time” benefit the most from on demand spare parts production.
This includes aerospace and aviation, defense and military, oil and gas, nuclear power, industrial manufacturing and heavy equipment, automotive, rail, marine and maritime, and mining and construction.
AM addresses spare parts challenges in these sectors because they “often operate equipment for decades, making conventional spare parts sourcing difficult and costly,” shares Dr. Poorganji.
“Many of these industries also manage aging infrastructure alongside increasingly complex global supply chains, making on demand manufacturing an effective way to improve resilience while reducing inventory requirements,” notes Rangarajan.
In addition, these same industries are known for holding onto extensive physical inventories, making them ideal candidates for 3D printing. “Maintaining a physical inventory creates challenges, as the cost of proper storage and the effective use of space over many years can be high. The volume of individual spare parts that may need to be stored can require large storage facilities also,” notes Buckley.
Specific Methods
Metal 3D printing technology encompasses a variety of processes, including but not limited to directed energy deposition (DED) and powder bed fusion (PBF).
For large geometries, Buckley says DED including wire arc AM (WAAM) are commonly used for large spare parts. “Their open build envelopes are not constrained by a powder bed, allowing them to produce large, near-net-shape components at high deposition rates.”
DED including WAAM “can be used in repair and maintenance to add material to existing components and support repair and refurbishment applications,” says Dr. Poorganji.
The team at Meltio believes DED or wire laser technologies are in demand for metal spare parts in industries like defense, aerospace, oil and gas, mining, and automotive.
“The most prevalent metal AM technology on the market today is PBF, and this is being qualified for spare part production in multiple industries. PBF technologies allow production of high-resolution components that can match the fidelity of the original components they create,” attests Richardson.
PBF is able to “produce titanium, aluminum, stainless steel, and Inconel components with exceptional tolerance and quality, which is ideal for high-performance applications such as heat exchangers, impellers, turbines, and fluidic devices,” shares Harris.
“The combination of complex geometries, print speed, and mechanical properties is a key driver for specific spare parts. PBF produces complex, near-net-shape spare parts with mechanical properties comparable to wrought or cast equivalents,” explains Buckley.
Furthermore, PBF technologies like electron beam PBF can print more challenging alloys efficiently, owing to a vacuum environment and an elevated-temperature build process, adds Buckley.
Haggin cites laser PBF (LPBF) as a preferred choice “when high precision, complex geometries, repeatability, and demanding material properties are required. In many spare parts applications, particularly those involving critical components, accuracy and performance are mission critical to the larger component.”
“There are increased requests for laser powder DED versus LPBF as demand for large parts grow. This is driven by the costs of storing and handling the large quantities of powder that large LPBF systems require,” foresees Gregory.
Overall “the optimal technology depends upon key factors such as part size, performance requirements, and production economics,” notes Dr. Poorganji.
Future Growth
Metal spare parts developed on demand via AM continue to influence the industries currently using it as well as others.
“Growth is expected in sectors facing geopolitical challenges, increasing supply chain pressures, aging infrastructure, and workforce challenges,” observes Dr. Poorganji.
Haggin foresees growth in all segments that currently use AM to manufacture metal spare parts on demand, in addition to “any that are pursuing digital inventories, supply chain localization, and asset lifecycle extension. As more organizations qualify their individual AM processes and establish digital part libraries, spare parts production is likely to shift from a reactive capability to a standard component of maintenance and logistics strategies.”
Rangarajan agrees and says much of that growth will be enabled by qualified digital inventories. “Rather than storing warehouses full of rarely used components, manufacturers will increasingly manage certified digital part files that can be produced through trusted manufacturing networks when required. The ability to design, digitally qualify, and certify both parts and manufacturing processes will further accelerate adoption as digital engineering tools continue to mature and gain broader industry acceptance to become a standard part of asset lifecycle management across many industrial sectors.”
Beyond the traditional industries using metal 3D printing for spare parts, Buckley also expects growth at “point of need; printing closer to where parts are required, rather than at a centralized location which further shortens the time from request to delivery. Reducing dependence on specific manufacturing regions and shortening supply chains remain critical to ensuring supply chain resilience for these industries.”
“We see a large opportunity in the defense industry that is leaning towards owning its intellectual property for spares and repairs so that they can produce them digitally, on demand. Most commonly, once technology and processes are adopted by the military, it eventually transfers to commercial applications, which is likely to impact heavy equipment, energy, and oil and gas industries,” suggests Harris.
Oil and gas industries are expected to expand their usage of AM for parts. “Currently, billions of dollars of spares sit in warehouses across the world ‘just in case’ a part fails in the field. Ultimately, 85 percent of these parts will be scrapped unused. If the supply chain lead time can be radically shortened through AM, then many billions of dollars of inventory can be eliminated,” explains Richardson.
Overcoming Limitations
There is hesitation when it comes to the use of AM in this segment.
Investment and mindsets are restricting for some, notes Haggin. “The upfront investment required to establish and validate an AM production workflow can be limiting, however, once qualified, metal AM is particularly well suited for spare parts applications. There is also a mindset change required if AM is new to an organization. The manufacturing habits of the past do not need to be eliminated, but there must be an openness to successfully adopt AM within a well-established manufacturing workflow.”
“The primary challenges are less about the printing technology itself and more about industrial implementation. For regulated and mission critical applications, qualifying parts, validating materials, and demonstrating repeatable production remain significant challenges. In many industries, spare part tooling or molds are also held by lower-tier suppliers in overseas locations, where long-term availability and access are not always predictable. Digital inventories combined with AM offer an opportunity to reduce this dependency by enabling qualified parts to be produced when and where they are needed,” believes Rangarajan.
Qualification of the technology remains a significant hurdle for regulated industries to get past, agrees Buckley. “Qualification of metal 3D printing to replace traditionally manufactured components can take a significant amount of time and cost to justify the replacement and demonstrate equivalence, along with adopting additional risk in changing the manufacturing process. Not all parts make sense to 3D print for a variety of reasons including cost, part geometry, and material. A case by case analysis must be performed to demonstrate that the economics of using metal 3D printing for specific spare parts is justified.”
“The biggest limitation for metal 3D printing in spare production is historically the price per part. Yes, metal 3D printing reduces tooling and warehousing costs, but it’s still an expensive cost per part,” admits Harris.
Spare Parts Production
AM reduces inventory costs, minimizes downtime, and supports aging equipment. The application of metal spare parts is a great use of the technology. Specifically, PBF and DED—including its derivatives—provide all of the benefits aforementioned and much more.
Sep2026, Industrial Print Magazine
