SBIR-STTR Award

Direct Digital Manufacturing (DDM) reduces cost and energy content of manufactured parts and enables producing parts-on-demand. The DDM process can reduce part acquisition time from several months to less than a few days. DDM reduces energy and machining cost by eliminating tooling and reducing by 10-20 times the buy-to-fly ratios of conventionally produced titanium parts. However, to achieve timely realization of these benefits, a rapid certification method is required for DDM of a wide range of metallic parts having diverse geometries. Presently, in order to ensure airworthiness, DDM parts must pass a lengthy and costly certification process. This significantly affects the Navys ability to use DDM to produce parts-on-demand. Thus, Keystone proposes an innovative method for part certification using a heuristic and adaptive approach and processing maps combined with non-destructive inspection, metallurgical review and limited mechanical property tests. The proposed project strategy envisions that an aircraft component can be composed of several standardized, building blocks of simple 3-dimensional geometric shapes and manufactured using 'sweet spot' parameters and practices. These representative geometric elements of a component, when fabricated using sweet spot process parameters and manufacturing practices, properly tested for defects, microstructure and mechanical properties, will enable establishment of a qualification algorithm and used for rapidly qualifying additional parts.

Benefit:
The qualification algorithm along with the database of test results for the building blocks of various geometric shapes and sizes will be a marketable tool. It will be tied to the particular DDM process used and can be marketed to all private and public sector industries for rapid qualification of parts.

Keywords:
NDI, NDI, adaptive, Heuristic, Prototype, Direct Digital Manufacturing, Qualification, Certification, process maps

Metal Digital Direct Manufacturing (MDDM) or layer-by-layer additive manufacturing is inherently green, produces near net shapes, reduces labor content, and does not require the use of special tooling to fabricate components. However, the process struggles to gain wide acceptance for producing aerospace and defense metal components due to two key issues. First, current powder and wire feed processes struggle to maintain high uniformity of part dimension and microstructure. Second, the current time required to qualify a MDDM component is so excessive it greatly restricts overall acceptance and usage of the process. In response, Keystone is developing, for implementation during this project, an adaptive feed-forward process control with feedback monitoring to ensure the process accounts for the thermal latency and thereby sustain aerospace levels of quality throughout the deposited component. Thus, this proposed project will utilize a wire feed, laser based MDDM system to build and validate a hybrid feed-forward / feedback monitoring capability, validation of a Rapid Process Qualification methodology and complete MDDM of a selected component.

Benefit:
The qualification algorithm with the database of test results for the building blocks of various geometric shapes and sizes will be tied to the particular DDM process used and can be marketed to all private and public sector industries for rapidly qualifying additional parts.

Keywords:
Heuristic, NDI, process maps, adaptive, Qualification, Prototype, Metal Digital Direct Mnufacturing