News | Oct 22, 2019

New Air Force-developed steel with 3D printing capability cuts costs while retaining strength

Now patented, USAF-96 steel formulation is available to U.S. businesses for commercialization

Using advanced additive manufacturing techniques, Army scientists are using an Air Force-invented steel alloy to print intricate geometries with ultra-high-strength. The steel is 50% stronger than what is commercially available.

David McNally/Army

A U.S. Air Force scientist has developed a state-of-the-art low alloy, high-performance steel that can be powdered and 3D printed into components, and other replacements parts for military and commercial applications.

The new steel was invented by Dr. Rachel Ann Abrahams of the U.S. Air Force Research Laboratory’s Munitions Directorate, according to a patent issued Tuesday.

Abrahams described the new USAF-96 steel, originally designed for bunker-buster bombs, as the perfect material for both military and commercial use.

“The actual task was to see if we could make it easier for the producers to make and reduce the cost by about 10%,” Abrahams said. “When they came back and said that it was going to be a 50% reduction in cost I think all of us were very, very excited and very surprised.”

Current steel production methods are costly due to the number of expensive alloys necessary, including tungsten and cobalt. Until now, new ways of manufacturing steel failed to retain strength while cutting costs.

“One major disadvantage to traditional high strength, high-performance steels is the relatively high cost of the steel, which arises from the alloy content, as well as the expensive manufacturing processes associated with such high-performance steels,” according to the Air Force’s newly issued patent. “To produce high strength steel, prior art compositions generally contain high levels of nickel, tungsten, and/or cobalt, which are relatively expensive elements and contribute to the high overall cost of the final steel product. “

To counter this, USAF-96 steel contains no tungsten or cobalt and is a low carbon, low nickel-alloy composition. In addition to its material cost advantage, USAF-96 Steel can be produced using standard air-melt production processes, at a substantially lower cost than prior methods.

The steel’s composition, along with specific thermal processing conditions, leads to the growth of beneficial nano-scaled carbides in a martensitic matrix, which allows it to possess high-performance characteristics even in heavier sections while using reduced the need for expensive components.

The new steel has also shown in testing to demonstrate through hardenability and toughness at -40°C, even with sections up to 4-inches in thickness, making it ideal for a range of applications from automotive components to structural bridge pieces to 3D printed parts for an M1 tank.

Using a method called Powder Bed Fusion, researchers at the U.S. Army Combat Capabilities Development Command’s Army Research Laboratory have converted Abrahams’ steel into a powder, which can then be melted into a repeating pattern by a 3D printer and thus building hyper-detailed components.

“You can really reduce your logistics footprint,” said Dr. Brandon McWilliams, a team lead in the lab’s manufacturing science and technology branch. “Instead of worrying about carrying a whole truckload, or convoys loads of spares, as long as you have raw materials and a printer, you can potentially make anything you need.”

Joan Wu-Singel, senior technology manager at TechLink, also praised the potential commercial uses for the steel, calling it “groundbreaking.”

“To see a potential 50% cost reduction in a material as ubiquitous as steel is huge,” Wu-Singel said. “Add to that the ability to use this formula for 3D-printed objects and you have an almost unlimited number of applications.”


Businesses interested in evaluating and licensing USAF-96 can contact Joan Wu-Singel at jwu-singel@montana.edu.