DOD STTR 24.A BAA

Active
No
Status
Closed
Release Date
November 29th, 2023
Open Date
January 3rd, 2024
Due Date(s)
February 21st, 2024
Close Date
February 21st, 2024
Topic No.
N24A-T023

Topic

Scalable Additive Friction Stir (AFS) for Multi-metal Deposition

Agency

Department of DefenseN/A

Program

Type: STTRPhase: Phase IYear: 2024

Summary

The Department of Defense (DOD) is seeking proposals for a Small Business Innovation Research (SBIR) program focused on the topic of "Scalable Additive Friction Stir (AFS) for Multi-metal Deposition". The objective of this research is to develop a portable or scaled-down friction stir deposition system that can structurally repair spot sizes or through holes down to 0.25" in diameter on 0.125" thick aluminum, titanium, and high-strength steel. Friction stir deposition is an emerging solid-state metal additive manufacturing process that allows for large-scale metal additive manufacturing, cladding, and structural repair. However, current commercial systems are not suitable for repairing small components on Navy and Marine Corps aircraft, which often have localized damage areas of less than 1". Additionally, the current systems are too large and not practical for remote or portable use on aircraft. The project will be conducted in two phases. In Phase I, the goal is to develop a concept for a friction stir deposition system that can deposit aluminum, titanium, and high-strength steel in areas less than 1 square inch on 0.125" thick substrates. Relevant machine parameters and deposition data will be captured to support modeling and model development. A Phase II testing plan will also be prepared. In Phase II, a prototype friction stir deposition system will be constructed and the material properties of the deposition of aluminum 7050-T7451, Ti6-4, and AerMet 100 alloys will be assessed. The properties of repaired substrates using feedstock of the same alloys will also be evaluated. A report documenting the design of the prototype system, system performance, and material testing results will be provided. A Phase III plan for prototype evaluation will be prepared, and the prototype system will be delivered to the Navy for evaluation. In Phase III, a full friction stir deposition system will be assembled and demonstrated to meet key deposition and material parameters, including mechanical properties related to strength and fatigue. The final deliverables will include a comprehensive report containing the design, deposition, and process and testing data, as well as the delivery of the full friction stir deposition system to the Navy. The development of a scalable or portable friction stir deposition system with multi-metal capability would have applications in the in-situ repair of commercial structures for aviation and other vehicle platforms. The solicitation notice can be found at this link. For more information, visit the Department of Defense SBIR/STTR Opportunities website.

Description

OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Advanced Materials; Sustainment

 

OBJECTIVE: Develop a portable or scaled-down / aircraft scale sized friction stir deposition system that is able to structurally repair spot sizes or through holes down to 0.25” in diameter on 0.125” thick aluminum, titanium, and high-strength steel.

 

DESCRIPTION: Rendering forging-like instead of casting-like properties, additive friction stir deposition (AFSD) is an emerging solid-state metal additive manufacturing process uniquely capable of large-scale metal additive manufacturing, cladding, and structural repair. Friction stir deposition systems are able to deposit high-quality aluminum, titanium and high-strength steel alloys, but current commercial systems as supplied by manufacturers like MELD and BOND use tool heads with a large surface area, approximately 1-1.25” in diameter [Ref 1]. This scale is useful for larger volume material deposition but is too large for the repair of most components on Navy and Marine Corps aircraft, which have small, localized damage areas of < 1”. In addition, this large tool geometry requires large backing forces to support a repair, which is likely going to be excessive for thin cross-section aircraft parts, potentially leading to part deformation during deposition [Ref 2]. The currently available systems are also very large and not practical for potential remote or portable use on aircraft.

 

PHASE I: Develop a concept for a friction stir deposition system that can deposit aluminum, titanium, and high-strength steel in areas < 1 square inch on substrates that are 0.125” thick. Capture relevant machine parameters and deposition data to support modeling/model development; such as high-resolution time-history data of the various parameters. At minimum, establish empirical/curve-fitting formulas to enable structural applications. Prepare a report to ONR and NAWCAD on design(s) and modeling. and prepare a Phase II testing plan.

 

PHASE II: Construct a prototype friction stir deposition system and assess the material properties, of the deposition of aluminum 7050-T7451, Ti6-4, and AerMet 100 alloys. Assess the properties of repaired 7050-T7451, Ti6-4, and AerMet 100 substrates using feed stock of the same alloys. Provide a report that documents the design of the prototype system, results of system performance, and results of material testing for the three alloys. Provide a Phase III plan to ONR and NAWCAD for prototype evaluation. Provide a prototype friction stir deposition system to NAWCAD for evaluation.

 

PHASE III DUAL USE APPLICATIONS: Assemble a full friction stir deposition system and demonstrate output meeting key deposition and material parameters, to include at least full mechanical properties related to strength and fatigue. Deliver a full friction stir deposition system to NAWCAD and a comprehensive final report containing the design, deposition, and process and testing data to ONR and NAWCAD.

 

The development of a scalable or portable AFSD print head with multi-metal capability would be directly applicable to in-situ repair of commercial structures for aviation and other vehicle platforms alike.

 

REFERENCES:

MELD Manufacturing. www.meldmanufacturing.com
Yu, Hang Z. “Additive Friction Stir Deposition.” Elsevier, Cambridge, MA, 2022. ISBN:978-0-12-824374-9.

 

KEYWORDS: Friction stir deposition, aerospace alloys, reduced scale, portable, in-situ, sustainment