In-situ additive manufacturing process monitoring

Project

In-situ additive manufacturing process monitoring

Additive manufacturing (AM), or 3D printing, has made many advances in recent years but it is still an extremely active area of research. This project focuses on a metal additive manufacturing process called laser powder bed fusion. Some applications of laser powder bed fusion include custom medical and dental components, monolithic parts with complex internal structures, customized metal alloys and lightweight automotive and aerospace components. One major challenge of this technology is to improve the quality of printed parts, which requires a better understanding of the process.

The goal of this project is to develop a new method of in-situ monitoring of the laser powder bed fusion additive manufacturing process. An instrumented build plate was designed, fabricated and installed in the Additive Manufacturing Metrology Testbed (AMMT) at the National Institute for Standards and Technology (NIST). An ultrasonic sensor attached to the bottom of the build plate detects acoustic emissions while the laser beam is scanning across the powder bed. A build plate heater was incorporated along with a tilting mechanism for better powder spreading. A thermal camera captures laser melt-pool images in-situ while another camera is used post-process to image powder denudation. Bolts with embedded strain sensors constrain the build plate and monitor the amount of residual stress as a 3D part is manufactured. The system developed in this project gives the AMMT additional potential measurement capabilities to investigate the AM process. The collaboration with NIST allows UNCC students to contribute to the understanding and advancement of additive manufacturing.