Investigation of Selective Laser Sintering of Zirconium Diboride Parts (PREPRINT)

摘要

This paper presents a study using the Selective Laser Sintering (SLS) process 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, energy density, 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) and separated from the main part, was first built in order to reduce thermal gradients. 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.