Improving the additive manufacturing process

Sometimes those of us indirectly energized by prospects for laser additive manufacturing are unaware of situations that may have occurred with industrial commercialization of the process. For example, distortions and stresses inherent in fabricating these complex geometries.

Researchers at the University of Pittsburgh's Swanson School of Engineering and motion control systems maker Aerotech (Pittsburg) received a National Science Foundation (NSF) grant to address these design issues by developing new, fast computational methods for additive manufacturing. Principal investigator, Associate Professor Albert To says, “Optimizing the design to compensate for residual distortion, residual stress, and post-machining requirements can take days or even months for these parts."

The group will first develop a simple, accurate thermomechanics model to predict residual stress and distortion in an additively manufactured part. Then they will develop a topology optimization method capable of generating designs with both free-form surfaces and machining-friendly surfaces. According to To, this will compensate for the geometric complexity and organic nature of additively manufactured parts, which contribute to their potential for distortion and post-machining problems. These approaches will then be developed and tested using real parts and design requirements provided by project partner Aerotech.

Stephen Ludwick, director of mechatronic research at Aerotech, expects that "the tools developed through this collaboration will allow us to produce the complex parts enabled by additive manufacturing with a minimum of trial-and-error and rework. This in turn allows us to design stiff and lightweight components in our high-speed motion systems, which are also used by other companies engaged in advanced manufacturing. By utilizing advanced mechanic theory, we hope to reduce design optimization of additive manufactured parts to minutes, thereby reducing the time of design life cycle.

Professor To says the US manufacturing base would widely adopt additive manufacturing and further improve the economic sustainability of the additive manufacturing process.

Read more about the NSF grant, http://www.industrial-lasers.com/articles/2016/08/upitt-to-develop-fast-computational-modeling-for-additive-manufacturing.html.