Effects of heat-treatment on the material properties of glass-ceramics samples fabricated by selective laser melting
Date of Issue2017-05-18
School of Mechanical and Aerospace Engineering
Selective laser melting is an additive manufacturing process that uses powder to fabricate geometrically complex parts with the help of computer-aided design. Despite the vast research on selective laser melting with metals, little is known for glass-ceramics. In this report, mechanical properties of a glass-ceramic - spodumene, subjected to heat-treatment is investigated. A series of experiments conducted includes heat-treatment, density measurement, x-ray diffraction analysis, and compression test. Cubic and cylindrical samples were fabricated by selective laser melting and subjected to different heat-treatment temperatures from 350ºC to 950ºC. After which, Archimedes’ technique was used to determine the density of the samples. The results showed no improvement in the density after heat-treatment. Furthermore, x-ray diffraction analysis conducted to identify the phases of the material revealed that α-, γ-, and β-spodumene were present in the material. The as-printed parts were partially crystalline before heat-treatment and only crystallized after heat-treatment. The percentage of porosity calculated for the two geometrically different samples was similar. In addition, compression test was also performed on the cylindrical samples, as they possessed less stress concentration points than the cubic samples. The results revealed that the higher the porosity of the parts, the higher the compressive strength. Since both geometries produced comparatively similar densities and porosities, selective laser melting fabrication of spodumene can be considered consistent.
Final Year Project (FYP)
Nanyang Technological University