Additive Manufacturing of Reactive Materials for Oxidation Resistance (ARMOR)
Abstract
Additive manufacturing (AM) has the potential to revolutionize part replacement and reduce supply chain limitations for the Departme,nt of Defense (DoD). In naval systems, there is significant overlap in parts that are candidates for replacement via AM and suscepti,bility to corrosion. Conflicting literature exists on how AM parts perform in corrosive environments, with some cases showing improv,ed corrosion resistance and others showing degraded performance relative to the equivalent wrought materials. The corrosion response, of AM materials must be clearly understood before wide acceptance of AM part replacement can be realized for Navy platforms. To wor,k toward acceptance of AM parts, investigations are needed into the underlying fundamental science on corrosion mechanisms and mitig,ation. Toward this goal, the Johns Hopkins University Applied Physics Laboratory (JHU/APL) team seeks to understand solidification b,ehavior of 316L AM materials in the Selective Laser Melting-Powder Bed Fusion (SLM-PBF) technique. Previously, the JHU/APL team disc,overed that laser scanning speed was critically linked to pitting corrosion response, the slower the laser the more stable the mater,ial was to pit formation. While slowing the laser helps to develop a more stable corrosion response, it is intractable for the DoD s,ince manufacturing time is critical. To address corrosion without slowing down manufacturing, JHU/APL is controlling solidification,by adding ceramic materials known to preferentially control nucleation and solidification response, enabling rapid manufacturing wit,h improved corrosion response. The objective of the FY22 effort is to understand the fundamental formation and degradation mechanism,s of ceramic-doped AM 316L, to determine optimized ceramic dopant concentration and laser processing conditions to achieve a stabili,zed microstructure and therefore superior corrosion resistance. The materials will be processed with the SLM-PBF technique and the c,orrosion response will be measured using microscopy, in-situ testing and ASTM standardized tests, to correlate microstructure and co,rrosion performance insights. Electrochemical testing, such as ASTM G61 potentiodynamic testing in simulated seawater, and ASTM G48,testing in ferric chloride, will be used to compare the standard control materials such as wrought 316L and AM 316L to our advanced,ceramic-doped materials and make real world comparisons of corrosion rates. If successful, this program will result in a highly corr,osion resistant material at accelerated manufacturing time, which would have a profound impact on sustainment and performance of cur,rent and future naval systems.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 08, 2022
- Source ID
- N000142212664
Entities
People
- Steven Storck
Organizations
- Johns Hopkins University
- Office of Naval Research
- United States Navy