Additive manufacturing has gained a lot of attention in the past few decades due to its significant advantages in terms of design freedom, lower lead time, and ability to produce complex shapes. One of the pivotal factors affecting the process stability and hence the part quality is the shielding gas flow in additive manufacturing. As extremely beneficial for the process, the shielding gas flow is often set at maximum supply to achieve enough gas cover over the substrate. This causes excessive quantity of shielding gas to be unutilized. Realizing the importance of shielding gas, various studies have been carried out to monitor and visualize the shielding gas, and one such technique is Schlieren imaging. Schlieren visualization has been used since the 1800s as a powerful visualization tool to visualize fluctuations in optical density. The Schlieren technique is highly effective for visualizing and optimizing shielding gas flow. This paper aims to provide an overview of Schlieren technique used for visualization of shielding gas and highlights the application of Schlieren in additive manufacturing.

Meeting Name

30th Annual International Solid Freeform Fabrication Symposium -- An Additive Manufacturing Conference, SFF 2019 (2019: Aug. 12-14, Austin, TX)


Mechanical and Aerospace Engineering

Document Type

Article - Conference proceedings

Document Version

Final Version

File Type




Publication Date

14 Aug 2019

Included in

Manufacturing Commons