Experimental and theoretical investigation of heat transfer in platform bed during polymer extrusion based additive manufacturing

Autor: Christian Lowery, Hardikkumar Prajapati, Darshan Ravoori, Ankur Jain
Rok vydání: 2019
Předmět:
Zdroj: Polymer Testing. 73:439-446
ISSN: 0142-9418
DOI: 10.1016/j.polymertesting.2018.11.025
Popis: Heat transfer plays a key role in polymer extrusion based additive manufacturing (AM) processes. Measurement and modeling of how temperature distribution on the platform bed changes with time during the dispensing of a polymer filament is of particular interest, as it determines the effectiveness of merging with neighboring filaments, and therefore, the properties of the built part. This paper reports infrared thermography based measurement of temperature field on the platform bed as a function of time during filament dispense and comparison with an analytical model based on moving heat source theory. Measurements identify two key heat transfer processes that influence temperature distribution on the bed. Data show that diffusion of thermal energy deposited on the bed with the filament and heat transfer from the hot nozzle tip both influence the temperature distribution on the bed. The relative contributions of these two sources of temperature rise on the bed are measured for different values of key process parameters. Measurement of temperature rise due to diffusion of thermal energy deposited on the bed is found to be in excellent agreement with an analytical model based on moving heat source theory. Evolution of the temperature field after completion of rastering of a line is measured. These data play a critical role in determining how effectively a filament merges with neighboring filaments. By identifying the key heat transfer processes that determine the temperature field on the platform bed, this work contributes towards thermal optimization of polymer-based additive manufacturing.
Databáze: OpenAIRE
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