Premium
Lost Mold Rapid Infiltration Forming of Mesoscale Ceramics: Part 1, Fabrication
Author(s) -
Antolino Nicholas E.,
Hayes Gregory,
Kirkpatrick Rebecca,
Muhlstein Christopher L.,
Frecker Mary I.,
Mockensturm Eric M.,
Adair James H.
Publication year - 2009
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2008.02627.x
Subject(s) - materials science , ceramic , fabrication , mold , composite material , cubic zirconia , microstructure , green body , medicine , alternative medicine , pathology
Free‐standing mesoscale (340 μm × 30 μm × 20 μm) bend bars with an aspect ratio over 15:1 and an edge resolution as fine as a single grain diameter (∼400 nm) have been fabricated in large numbers on refractory ceramic substrates by combining a novel powder processing approach with photoresist molds and an innovative lost‐mold thermal process. The colloid and interfacial chemistry of the nanoscale zirconia particulates has been modeled and used to prepare highly concentrated suspensions. Engineering solutions to challenges in mold fabrication and casting have yielded free‐standing, crack‐free parts. Molds are fabricated using high‐aspect‐ratio photoresist on ceramic substrates. Green parts are formed using a rapid infiltration method that exploits the shear thinning behavior of the highly concentrated ceramic suspension in combination with gelcasting. The mold is thermally decomposed and the parts are sintered in place on the ceramic substrate. Chemically aided attrition milling disperses and concentrates the as‐received 3Y‐TZP powder to produce a dense, fine‐grained sintered microstructure. Initial three‐point bend strength data are comparable to that of conventional zirconia; however, geometric irregularities (e.g., trapezoidal cross sections) are present in this first generation and are discussed with respect to the distribution of bend strength.