Sintering and properties of sialons derived from kaolin

Journal Article · Fri Jul 01 00:00:00 EDT 1988 · Advanced Ceramic Materials; (USA)

DOI:https://doi.org/10.1111/j.1551-2916.1988.tb00228.x· OSTI ID:5946180

Bandyopadhyay, S; Mukerji, J ^[1]

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1. Central Glass and Ceramic Research Institute, Calcutta (India)

The sintering behavior of {beta}{prime}-sialon (Z = 2) derived from kaolin (Al{sub 2}O{sub 3}{center dot}2SiO{sub 2}{center dot}2H{sub 2}O) without additives is described. The refractoriness of the product increased with increasing nitrogen content. A product of 74% theoretical density was obtained after sintering at 1,700{degree}C a synthesized product having 79.17% theoretical N{sub 2} content. A fully dense product could not be made. The MOR of sintered specimens prepared from samples containing 79.17% theoretical nitrogen content retained it room-temperature strength up to 1,350{degree}C after showing a brief increase to 1,000{degree}C. The total creep strain for the same sample conducted at a load of 18 MN {center dot} m{sup {minus}2} and at a temperature of 1,300{degree}C was 0.06% in 20 h and 2.72% at 1,400{degree}C in 30 h. The oxidation curve increased initially and leveled thereafter. The maximum weight gain at 1,350{degree}C after 72 h was 4 mg/cm{sup 2}. The activation energy was calculated to be 47 kcal/mol. The thermal-expansion coefficient was 2.65 {times} 10{sup {minus}6}/{degree}C from room temperature to 1,000{degree}C. Corrosion in molten aluminum and fluoride baths is described.

• OSTI ID: 5946180
• Journal Information: Advanced Ceramic Materials; (USA), Vol. 3:4; ISSN 0883-5551
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM OXIDES
FLEXURAL STRENGTH
OXIDATION
SINTERING
SILICON NITRIDES
ACTIVATION ENERGY
CREEP
EXPERIMENTAL DATA
KAOLIN
MEASURING METHODS
ALUMINIUM COMPOUNDS
CHALCOGENIDES
CHEMICAL REACTIONS
CLAYS
DATA
ENERGY
FABRICATION
INFORMATION
MECHANICAL PROPERTIES
NITRIDES
NITROGEN COMPOUNDS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PNICTIDES
SILICON COMPOUNDS
360201* - Ceramics
Cermets
& Refractories- Preparation & Fabrication
360203 - Ceramics
Cermets
& Refractories- Mechanical Properties
360205 - Ceramics
Cermets
& Refractories- Corrosion & Erosion