Colloidal processing of chemically prepared zinc oxide varistors. Part 2, near net shape forming and fired electrical properties.
Chemically prepared zinc oxide powders were processed for the production of high aspect ratio varistor components (length/diameter >5). Near-net-shape casting methods including slip casting and agarose gelcasting were evaluated for effectiveness in achieving a uniform green microstructure that densifies to near theoretical values during sintering. The structure of the green parts was examined by mercury porisimetry. Agarose gelcasting produced green parts having low solids loading values and did not achieve high fired density. Isopressing the agarose cast parts after drying raised the fired density to greater than 95%, but the parts exhibited catastrophic shorting during electrical testing. Slip casting produced high green density parts, which exhibit high fired density values. The electrical characteristics of slip-cast parts are comparable with dry-pressed powder compacts.
- Research Organization:
- Sandia National Laboratories
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 1003985
- Report Number(s):
- SAND2003-2841J
- Journal Information:
- Proposed for publication in the Journal of Materials Research., Journal Name: Proposed for publication in the Journal of Materials Research. Journal Issue: 5 Vol. 19; ISSN JMREEE; ISSN 0884-2914
- Country of Publication:
- United States
- Language:
- English
Similar Records
Advanced powder processing
Tensile strength of dried gelcast green bodies