Masters Theses

Keywords and Phrases

Additive manufacturing; Image processing; Infrared thermography; Process monitoring


"Laser metal deposition as an additive manufacturing technique has been proven to possess the capability for fabricating complex, intricate geometries and excellent material properties through material deposition. Accurate manufacture of such geometric features would require precise control over the material deposition process. The need of the hour are process monitoring and analyses mechanisms that are crucial in ascertaining the occurrence of the intended actions during deposition while also serving as effective learning tools. The current work involved developing and incorporating an Infra-Red (IR) camera as a process monitoring tool for laser metal deposition. Using the IR camera the thermal dynamics of the deposition processes under the control of the feedback systems were captured and analyzed to realize the changes in the material close to solidus temperature. The analysis confirmed the logic behind the control system and was successful in helping identify the ideal process parameters which were quantified using a set of experiments. The sub-sequent effort was focused on further disseminating thermographic data to attain details about the material above the solidus temperature. Employing image processing techniques pertaining to edge detection, regions that encompass the material above the solidus temperature were successfully identified. IR camera data was also used to track the regions of interest through the deposition and make other characteristic observations pertaining to phase change. To further test the sensitivity of this technique a series of experiments with varying power, track length and substrate size were performed. The developed methodology proved successful in identifying the regions of interest with a high degree of sensitivity and repeatability. Comprehensive insights into the physics of the process were also successfully obtained."--Abstract, page iii.


Liou, Frank W.

Committee Member(s)

Newkirk, Joseph William
Kinzel, Edward C.


Materials Science and Engineering

Degree Name

M.S. in Manufacturing Engineering


Missouri University of Science and Technology. Department of Mechanical and Aerospace Engineering (Manufacturing Engineering)


Missouri University of Science and Technology

Publication Date

Spring 2015


x, 53 pages

Note about bibliography

Includes bibliographical references (pages 51-52).


© 2015 Sreekar Karnati, All rights reserved.

Document Type

Thesis - Open Access

File Type




Subject Headings

Manufacturing processes
Infrared imaging

Thesis Number

T 10680

Electronic OCLC #


Included in

Manufacturing Commons