Keywords and Phrases
Additive Manufacturing; Direct Metal Deposition; Micro-hardness; Peltier effect; Powder feed; Thermo-electric cooling
”Nickel hard-surfacing alloys are replacing hard Chromium coatings due to their excellent wear and corrosion-resistant properties. In laser cladding of these alloys, however, these properties can vary across the height of the deposit due to an accumulation of excess heat generated in the deposit during the process. This may result in uneven wear of the clad parts which can be detrimental for practical purposes. The research objective is to develop an in-situ cooling system that works in line with the laser deposition system to extract the excess heat buildup and reduce the variation in the hardness of the Ni-based clad alloy deposit across its height.
This thesis discusses a new network system with two-way communication between the developed cooling system and the laser system. A thermo-electric cooling system was decided on to act as the optimal cooling system. The two systems work in-hand with each other to automate the process of extracting heat from the deposits. The study focusses on developing the cooling system, integrating the system into the existing laser system, laser deposition with the new integrated system, sample preparation and mechanical testing. Comparative micro-hardness tests have been performed on deposits made with the new system and without. The results indicate a significant reduction in the variation of the microhardness across the deposit along with an enhancement in the mean hardness value of the clad material”--Abstract, page iii.
Liou, Frank W.
Mechanical and Aerospace Engineering
M.S. in Manufacturing Engineering
Missouri University of Science and Technology
ix, 48 pages
© 2017 Raghu Ram Kolla, All rights reserved.
Thesis - Open Access
Electronic OCLC #
Kolla, Raghu Ram, "In-situ control of substrate temperature in additive manufacturing to homogenize micro-hardness of laser clad deposits using thermo-electric cooling" (2017). Masters Theses. 8050.