US Navy installs first welded 3D printed metal part on operational Virginia-class submarine.

The U.S. Navy has installed its first welded 3D-printed metal component aboard the Virginia-class submarine USS Washington (SSN-787), marking a first in operationalizing additive manufacturing within the fleet.

The copper-nickel flange, produced through metal additive manufacturing and certified for submarine use, was rapidly produced and integrated during maintenance at Portsmouth Naval Shipyard, reducing supply chain delays, supporting faster maintenance cycles, and strengthening the operational availability of the U.S. attack submarine fleet.

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The installed component is a copper-nickel flange, a critical element typically used in critical piping systems and structural interfaces within submarines, where it must withstand high pressure, corrosion, and continuous operational stress. (Picture source: U.S. Navy)

On March 12, 2026, Portsmouth Naval Shipyard completed the first installation of a welded metal additive-manufactured (AM) component on a U.S Navy submarine, marking a step toward operational use within the fleet. The component, a copper-nickel flange installed aboard USS Washington (SSN-787), represents the first instance of a 3D-printed metal part being welded and certified for a U.S. in-service nuclear-powered attack submarine. Inspection and testing were completed on March 9, 2026, followed by installation on March 18, indicating a compressed validation and deployment timeline within a limited maintenance availability period.

The initiative followed a directive issued by Vice Adm. Robert Gaucher to accelerate additive manufacturing integration across the submarine force. The effort was executed within a public shipyard environment rather than a private industrial setting, which has implications for scaling production and qualification processes across naval maintenance infrastructure. The flange itself is a copper-nickel component used in piping systems, where it functions as a connection interface between sections of piping or between piping and onboard equipment, requiring resistance to corrosion, pressure, and mechanical stress. 

Copper-nickel alloys are commonly selected in naval environments due to their resistance to seawater corrosion and biofouling, particularly in cooling and fluid transfer systems. Its selection was driven by a specific operational requirement identified during maintenance planning, indicating that additive manufacturing is being applied to resolve immediate supply constraints, as a conventionally manufactured flange would otherwise require longer procurement timelines. The functional requirements of the 3D-printed flange include maintaining pressure integrity, dimensional tolerances compatible with existing piping systems, and long-term durability under cyclic loading conditions.

The use of such a component in an operational submarine environment indicates the U.S. Navy's confidence in the material properties and production consistency of additively manufactured metals. The manufacturing process relied on 3D metal printing techniques, where the flange was produced layer by layer from a digital model prior to delivery to the shipyard. This allows for reduced lead times compared to traditional casting or machining, particularly for components with limited production runs or complex geometries. The part was sourced through coordination with a maritime industrial base center of excellence, indicating integration between naval maintenance facilities and external additive manufacturing providers.

Once produced, the component was delivered to the shipyard’s receipt inspection division for verification before entering the certification process. The shift from subtractive to additive production reduces material waste and enables more flexible manufacturing, particularly for legacy components where tooling may no longer be available. This case demonstrates the use of additive manufacturing as a supply chain solution, but also reflects the establishment of a new distributed production model for the U.S. Navy's sustainment requirements. The certification process for the flange required a full set of inspections, material testing, and weld qualification procedures to ensure compliance with naval standards.

This included verifying mechanical properties, dimensional accuracy, and compatibility with existing welding techniques used in submarine maintenance. A dedicated team of engineers and trade specialists conducted a full weld qualification on the additively manufactured material, which differs from traditional wrought or cast metals in microstructure and behavior under heat. The process required validating that the weld joint would maintain integrity under operational conditions, including pressure fluctuations and long-term exposure to seawater environments. The qualification, therefore, represents a first instance of certifying a welded additive-manufactured component for submarine use within a public shipyard.

This also establishes a precedent for future certification efforts and provides a baseline for expanding the range of approved additively manufactured parts inside American submarines. The installation took place aboard USS Washington, a Virginia-class submarine commissioned on October 7, 2017, with a displacement of about 7,800 tons and powered by an S9G nuclear reactor enabling extended deployments without refueling. The submarine is designed for multi-mission operations, including anti-submarine warfare, anti-surface warfare, intelligence collection, surveillance, reconnaissance, and precision strike missions. These vessels operate in both deep ocean and littoral environments, requiring systems that can withstand variable pressure, temperature, and salinity conditions.

Integrating an additively manufactured component into such a system indicates that the technology is being applied within high-performance operational contexts rather than limited-support roles. The submarine had entered dry dock for scheduled maintenance and system upgrades prior to the installation, providing the opportunity to integrate the new component. This installation serves as an initial case for broader adoption across the Virginia-class fleet, but also reflects efforts to address maintenance backlogs and improve turnaround times for the U.S. submarine fleet. From an industrial perspective, the use of additive manufacturing for submarine components addresses specific constraints in the current U.S. naval supply chain, particularly for parts with long procurement cycles or limited supplier bases.

Traditional manufacturing methods for specialized components can involve lead times measured in months, especially when tooling or casting processes are required. Additive manufacturing enables production on demand, reducing dependency on legacy supply chains and allowing for faster response to maintenance requirements. This approach can shorten repair timelines and increase the availability of submarines for deployment. It also supports the development of a more flexible industrial base, where production can be distributed across multiple facilities rather than centralized in a limited number of suppliers. The involvement of a maritime industrial base center of excellence indicates a structured effort to mitigate bottlenecks in U.S. submarine maintenance and sustainment. 

At a strategic level, the installation of this component reflects a broader shift in how the U.S Navy approaches sustainment and readiness, moving toward incorporating advanced manufacturing technologies into operational workflows. The ability to produce and certify components more rapidly supports sustained operational tempo and reduces vulnerability to supply chain disruptions. Additive manufacturing offers cost and time advantages, particularly for low-volume or complex parts, but its adoption requires addressing certification challenges and ensuring consistent material performance.

The process of qualifying new materials and production methods remains resource-intensive, which may limit the speed of widespread adoption. Material constraints also restrict the range of components currently suitable for additive manufacturing, requiring continued development of approved material specifications. Despite these limitations, the integration of a welded additively manufactured component into an operational submarine represents a concrete step toward expanding the role of advanced manufacturing in naval operations. In short, this simple 3D-printed flange indicates a gradual but measurable transition toward a more adaptable and resilient sustainment model within the U.S. Navy.

Written by Jérôme Brahy

Jérôme Brahy is a defense analyst and documentalist at Army Recognition. He specializes in naval modernization, aviation, drones, armored vehicles, and artillery, with a focus on strategic developments in the United States, China, Ukraine, Russia, Türkiye, and Belgium. His analyses go beyond the facts, providing context, identifying key actors, and explaining why defense news matters on a global scale.