Rheology Control of Highly Concentrated Mullite Suspensions with Polyelectrolyte for Robocasting
- Sandia National Laboratories
Highly concentrated, aqueous mullite slurries were characterized and stabilized at solids concentrations as high as 60 vol% using less than 2 vol% of an organic polyelectrolyte dispersant. The maximum slurry concentration (60 vol%) is within 3 vol% of the maximum consolidated density of the slurry. The slurries were subsequently cast into parts by a solid freeform fabrication technique termed robocasting and characterized. Sedimentation analysis and viscometry provided the means of slurry characterization, while knowledge of polyelectrolyte and interparticle forces was used to interpret the sedimentation and viscometry data. Through proper control of slurry conditions, pseudoplastic mullite slurries were fabricated for use in the robocasting process. The slurries were robocast at 52 vol% solids and subsequently yielded a green density of 55 vol%. Fired densities of the robocasted slurries were high, with mullite >96% dense at 1,650 C.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (US); Sandia National Labs., Livermore, CA (US)
- Sponsoring Organization:
- US Department of Energy (US)
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 759857
- Report Number(s):
- SAND2000-1484J
- Journal Information:
- Journal of the American Ceramics Society, Journal Name: Journal of the American Ceramics Society
- Country of Publication:
- United States
- Language:
- English
Similar Records
Robocasting of Ceramics and Composites Using Fine Particle Suspensions
Processing of Silicon Nitride Ceramics from Concentrated Aqueous Suspensions by Robocasting