4 research outputs found
Optimization of Selective Laser Sintering Process for Fabrication of Zirconium Diboride Parts
Selective Laser Sintering (SLS) was investigated to fabricate Zirconium Diboride
(ZrB2) parts for ultra-high temperature applications. Experiments were conducted to
determine values of SLS process parameters (laser power, scan speed, line spacing, and
layer thickness) that can be used to build ZrB2 parts with high integrity and sharp
geometrical features. A sacrificial plate with a proper number of layers (determined from
experimentation) separated from the main part was built in order to reduce thermal
gradients when building the main part. The sacrificial plate was found to assist in
eliminating cracks in the bottom of the main part. The fabricated green parts then went
through post processing steps including binder burnout and sintering at proper
temperature schedules, to remove the binder and sinter the ZrB2 particles. The test bars
after sintering had an average relative density of 87% and an average flexural strength of
250 MPa.Mechanical Engineerin
Investigation of selective laser sintering of zirconium diboride parts
This research investigates the fabrication of three-dimensional parts from ZrBâ‚‚, an ultra high temperature ceramic (UHTC), using the selective laser sintering (SLS) process. Based on an experimental investigation, optimum values for the SLS parameters (scan speed, laser power, energy density, scan spacing and layer thickness), used on a DTM Sinterstation 2000, were determined to build green ZrBâ‚‚ parts with high integrity and sharp geometrical features. This was done by melting the polymer binder used to bond the ceramic particles layer-by-layer according to the cross-section of a CAD model. The use of a sacrificial plate to eliminate cracks in the bottom of the part was demonstrated and the proper number of separation layers between the sacrificial plate and the main part was determined experimentally. The fabricated green parts went through post processing steps including binder burnout and sintering in furnaces at appropriate temperature schedules to remove the binder and sinter the ZrBâ‚‚ particles. Several test bars were fabricated and determined to have good properties with an average relative density of 87% and an average flexural strength of 250 MPa --Abstract, page iv
To entrepreneur or not to entrepreneur? How identity discrepancies influence enthusiasm for academic entrepreneurship
publishedVersio
Investigation of Laser Sintering for Freeform Fabrication of Zirconium Diboride Parts
This paper presents a study wherein the Laser Sintering (LS) process is used to perform additive manufacturing of zirconium diboride (ZrB2) parts. Experiments were conducted to determine values of LS process parameters (laser power, scan speed, energy density, line spacing, and layer thickness) that can be used to improve building of ZrB2 parts. A sacrificial plate with a proper number of layers was first constructed in order to reduce thermal gradients in building the main part. The sacrificial plate was found to eliminate cracks that would otherwise occur in the bottom of the main part. The fabricated green parts went through post-processing steps, including binder burnout and sintering at appropriate heat treatment schedules, to remove the binder and sinter the ZrB2 particles. The test bars after sintering had an average relative density of 87% and an average flexural strength of 250 MPa