Low-Inclusion Content for High-Grade Steel Material Used in Gear-and-Bearing Components

RT&L FOCUS AREA(S): General Warfighting Requirements (GWR) TECHNOLOGY AREA(S): Materials / Processes The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with section 3.5 of the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws. OBJECTIVE: Design and develop a steel processing method to dramatically reduce the inclusion content of steel bar stock for current gear material X-53 double vacuum melt (AMS 6308) beyond levels currently available commercially in steel intended for use in aerospace-level gear-and-bearing components. DESCRIPTION: The naval aviation community, as owner and operator of aerospace systems, continuously seeks improvement in the manufacturing arena. The Navy occasionally faces issues with inclusions in aerospace components made from the current gear material X-53 double vacuum melt (AMS 6308). Developing a cost-neutral manufacturing technology that would allow higher grade steel material with dramatically lower inclusion content would increase fatigue life, improve safety, and lower sustainment costs for a steel component. The goal is a lower inclusion content level of 90% objective (75% threshold) than is documented in the current inclusion standard in the material standard AMS 6308. This would result in a decrease in cost to the Government and/or original equipment manufacturers (OEMs), while improving homogenous performance of the material in production creation of components and use of those components. Transmission components, such as gears and bearings, are made from steel in the 4 to 14 inch diameter bar sizes. Determination of the size, type, distribution, and location of inclusions within the created material is the desired output. Comparison to current gear material X-53 double vacuum melt with ASTM E45 inspection standard is required to verify improvement. PHASE I: Develop, design, and demonstrate feasibility of an analytical concept of technology allowing lower level of inclusion content. Projection of size, type, distribution, and location of inclusions within the bar stock are desired identifiable characteristics of a material. Exogenous inclusions such as refractory material are the primary concern, but indigenous inclusions are also a concern. Reduction in both types of inclusions is desired. The Phase I effort will include prototype plans to be developed under Phase II. PHASE II: Develop and demonstrate a prototype production process with creation of sample material. Determination of the size, type, distribution, and location of inclusions within the created material are the desired output. Comparison to current gear material X-53 double vacuum melt with ASTM E45 standard is required to verify improvement. PHASE III DUAL USE APPLICATIONS: Finalize and demonstrate a larger scale production process with creation of a heat lot of steel material. Determine the size, type, distribution, and location of inclusions within the created material output. Comparison to current gear material X-53 double vacuum melt with ASTM E45 standard and fatigue test transverse created specimens to verify improvement. Material failure due to inclusions limits the useful life of gear-and-bearing components. Commercial gear-and-bearing products would have higher and more predictable life. Aerospace, Industrial Machine, and other applications that require more predictable run time to avoid downtime and component changes would benefit from the technology. REFERENCES: 1. SAE Technical Standards Board. AMS6308F: Steel, bars and forgings 0.90Si-1.0Cr-2.0Ni-3.2Mo-2.0Cu-0.10V (0.07-0.13C) vacuum arc or electroslag remelted. SAE International, May 16, 2018. https://www.sae.org/standards/content/ams6308f/. 2. Sub-committee E04-09 on Inclusions. ASTM E45 - 18a Standard Test Methods for Determining the Inclusion Content of Steel. ASTM International. http://www.astm.org/cgi-bin/resolver.cgi?E45. 3. ISO 4967:2013 Steel Determination of content of non-metallic inclusions Micrographic method using standard diagrams. International Organization for Standardization, July 2013, https://www.iso.org/standard/63156.html.