Microwave (Hybrid) Heating of Alumina at 2.45 GHZ: I. Microstructural Uniformity and Homogeneity
Abstract
Microwave (hybrid) heating (MHH) is a unique combination of microwave (MW)material interaction and conventional radiant/conduction mechanisms that facilitates the attainment of very high heating rates in a 2.45 GHz, multimode MW cavity. Microstructural uniformity and homogeneity of dry-pressed green samples of pure, undoped alumina with (MHH relative to conventional fast firing (CFF) has been studied. The confluence of the two heating mechanisms (with MHH) results in an improved parity in temperatures across specimen cross-sections vis-a-vis CFF and stand-alone MW (SMW) sintering. This enhanced parity in temperatures (with MHH) can be said to be responsible for the better microstructural homogeneity and improved mechanical properties relative to CFF. Sintering of larger (20 gm vs. 6 gm) samples with MHH shows evidence of a definitive mass dependence on the MHH phenomena. Larger masses show a better parity in temperatures between the surface and interior of the sample. Consequently, this results in enhancements in the homogeneity of the microstructure, and improved and more uniform mechanical properties relative to the smaller MHH and CFF samples.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 27, 1992
- Accession Number
- ADP007744
Entities
People
- Arindam De
- David E. Clark
- E. D. Whitney
- Iftikhar Ahmad
Organizations
- University of Florida