Effects of the Sintering Process on Properties of Triaxial Electrical Porcelain from Ugandan Ceramic Minerals

Title: Effects of the Sintering Process on Properties of Triaxial Electrical Porcelain from Ugandan Ceramic Minerals
Authors:

Peter W. Olupot, Stefan Jonsson, and Joseph K. Byaruhanga

Keywords: Dwell time, Microstructure, Porcelain, Strength
Issue Date: September 2013
Abstract: Porcelain specimens were fired at 6°C/min to 1250°C (dwell time 0.5-3h) and cooled at 6°C/min to room temperature. Additionally, three different slower firing/cooling cycles were tried. Sintering profile and effects on MOR, crystalline phase content and morphology were investigated using dilatometry, 4-point bending strength, XRD and FEG-SEM respectively. Industrial-sized specimens prepared using the promising cycle were tested basing on the ANSI standards. Increasing dwell time from 1h to 3h at peak temperature of 1250°C resulted in neither a significant effect on the quartz and mullite content nor MOR. Reducing the firing/cooling rate to below 6°C/min, for peak temperature of 1250°C (dwell time of 1h) does not result in improvement of strength of porcelain. The industrial sized specimen exhibited flashover voltages of 20.3kV (dry) and 9.3kV (wet) respectively, transverse strength of 12.5kN and bulk density of 2.27g/cm3, which are satisfactory. There was however dye penetration during porosity test.
Published in: World Academy of Science, Engineering and Technology 77 2013

Attachments

Attachment Name Attachment Type
Effects of the Sintering Process on Properties of Triaxial Electrical Porcelain from Ugandan Ceramic Minerals DOC PDF PS