An Overview of DARPA Open Manufacturing Program: tiFAB

The established paradigm of material qualification utilizes large coupon-level testing programs across multiple heats and lots of material created by a process in an attempt to capture any effects of process variability on the material properties. However, the fundamental relationships between processing and product characteristics are not necessarily thoroughly understood, and as a result there is always a risk that technical issues will emerge during the product development cycle. Additive manufacturing presents increased product development risk as the layer-by-layer processing parameters used and resulting geometrically-sensitive thermal conditions are often not consistent from one design to another.

In 2012, the DARPA DSO funded several programs under the initiative “Open Manufacturing” in order to change the established traditional qualification methods to manufacturing. The Boeing program “tiFAB” under DARPA Open Manufacturing employs an informatics-based approach, using artificial neural networks to identify process-microstructure-property relationships after building a pedigreed design knowledge base of material, process, and property data and metadata. These relationships are then linked to existing metallurgical equations and models and made probabilistic. The program focuses on a specific additive manufacturing technology, electron beam additive manufacturing (EBAM) of Ti-6Al-4V, as a demonstration. However, the underlying framework is meant to be applied to any advanced manufacturing process.

This presentation will provide an overview of the program’s framework as well as the data from the supporting material fabrication and various post-processing heat treatments including AM-a+β stress relief, AM-a+β HIP, and AM-β annealing. This material is based upon work supported by the Defense Advanced Research Projects Agency under Contract No. HR0011-12-C-0035.