Thermal-mechanical loading on three-dimensional printing lattice structures

• Main Author: Muhammad Hafizuddin Hashim
• Other Authors: Fei Duan
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2021
• Subjects: Engineering::Mechanical engineering
• Online Access: https://hdl.handle.net/10356/150930
• Institution: Nanyang Technological University

Lattice structures are designed and manufactured for many different industries for various purposes. Numerous studies have been conducted to analyse the mechanical performances of lattice structures. Previous study conducted for thermal performance of Body-Centred-Cubic (BCC) lattice structures, of which different struct radius were fabricated using Selective Laser Melting (SLM), was investigated on their heat conduction performance through 1-D steady state heat conduction analysis. It was concluded that struct radius and effective thermal conductivity of SLM printed BCC samples vary exponentially. However, it was observed that studies for thermal performance of other lattice structures, such as FCC and octet truss were still lacking in the current field. Thus, in this project, thermal experiment was replicated to study the behaviours and to determine the effective thermal conductivity of BCC, FCC and octet truss lattice structure with a unit cell of 6mm and 0.5mm strut radius. Heat flux of 2430.56W/m^2, 3819.44W/m^2 and 5729.1W/m^2 was carried out across all lattice structure to diversify its data. It was concluded that the octet truss lattice structure exhibits the highest thermal conductivity across increasing heat flux, ranging from 18.1 to 20.3, while BCC ranges from 7.25 to 8.65 and FCC ranges from 4.96 to 5.31 accordingly. Lastly, this project aims to study the relationship between its thermal performance and compressive strength as its function of its total performance level. Uniaxial compression test was carried on BCC, FCC, and octet truss lattice structure test sample to obtain its compressive strength. In conclusion, the octet truss lattice structure exhibits the highest total performance, followed by BCC and FCC. In the future work, varying parameters of sample can be printed and tested for both its compressive strength and heat conduction testing to diversify its data. A simulation for its compressive strength could be implored to better obtain data as SLM of samples takes relatively a long time to produce.