Lockheed Martin expects to reduce titanium part-production costs for the F-35 fighter by applying this additive manufacturing technology in place of forging.
Editor-in-Chief, Modern Machine Shop
Sciaky Inc., a company based in Chicago, Illinois, has fewer than 60 employees today, but company leaders are preparing for its workforce to double or triple in the years to come. The company specializes in large-scale welding systems, but soon, the bulk of its activity might focus on a welding-derived technology for additive manufacturing. “Electron beam direct manufacturing,” or EBDM, holds considerable promise for defense aeronautics company Lockheed Martin—which intends to use it to reduce titanium part-production costs for the F-35 Joint Strike Fighter. Lockheed Martin has joined Sciaky in a U.S. Department of Defense “Mentor-Protégé” agreement aimed at advancing the technology to realize these savings.
EBDM uses an electron beam to melt a titanium wire within a vacuum environment, applying titanium in a continuous feed that might be 1/8 inch high by 1/2 inch wide. By adding layer upon layer of titanium in this way, EBDM can build complex titanium parts quickly, including aircraft structural parts. The only limit on the size of the part is the size of the chamber used to contain the vacuum.
In aircraft production, savings would come from replacing forgings. EBDM, unlike forging, does not require a die. Also, while the EBDM part does have to be CNC machined to its finished dimensions, the amount of machining is not nearly as great as that of forging, because the excess stock on an EBDM part is much less. Therefore, the additive process reduces die costs, material costs and machining costs together—any one of which might produce significant savings. On just one F-35 component, the 10-foot-long flaperon spar, Lockheed Martin has projected EBDM to save $100 million across the production life of the plane. At least 10 other forged titanium parts on the F-35 have been identified for similar potential replacement with EBDM structures.
The technology has been under development for 10 years, Sciaky says. The breakthrough came in the last 2 to 3 years, with the development of adaptive closed-loop control over key thermal and positioning parameters of the process. This control elevated EBDM from a niche process requiring an expert operator to a means of making parts that is viable for production. According to the company, grants from the U.S. government’s Small Business Innovation Research program were critical in funding this part of the technology’s development.