Advanced Solid Geopolymer Formulations for Refractory Applications

Cement, as a construction material, has low thermal resistance, inherent fire resistance, and is incombustible up to a certain degree. However, the loss of its mechanical performance and spalling are its primary issues, and it thus cannot retain its performance in refractory applications. The present study explores the performance of geopolymer formulations that have excellent fire resistance properties for potential refractory applications. This study is unique, as it investigates advanced solid geopolymer formulations that need only water to activate and bind. Various solid geopolymer formulations with fly ash as a precursor; potassium hydroxide and potassium silicate as activators; and mullite and alumina as refractory aggregates were studied for their compressive strength at up to 1100 °C and compared with their two-part conventional liquid alkaline geopolymer counterparts. Advanced solid geopolymer formulations with mullite and alumina as refractory aggregates had mechanical strength values of 84 MPa and 64 MPa post-1100 °C exposure and were further exposed to ten thermal cycles of 1100 °C to study their fatigue resistance and post-exposure compressive strengths. The geopolymer sample with mullite as a refractory aggregate yielded 115.2 MPa compressive strength after the fourth cycle of exposure. This sample was also studied for its temperature distribution upon direct flame exposure. All the geopolymer formulations displayed a drop in compressive strength at 600 °C due to viscous sintering and then a rise in strength at 1100 °C due to phase transformation. X-ray diffraction studies revealed that the formation of crystalline phases such as leucite, sanidine, and annite were responsible for the superior strengths at 1100 °C for the alumina- and mullite-based geopolymer formulations.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:17

Enthalten in:

Materials (Basel, Switzerland) - 17(2024), 6 vom: 18. März

Sprache:

Englisch

Beteiligte Personen:

Hussain, Shaik [VerfasserIn]
Amritphale, Sudhir [VerfasserIn]
Matthews, John [VerfasserIn]
Paul, Niloy [VerfasserIn]
Matthews, Elizabeth [VerfasserIn]
Edwards, Richard [VerfasserIn]

Links:

Volltext

Themen:

Advanced solid geopolymer
Compressive strength
Journal Article
Refractory
Thermal fatigue resistance

Anmerkungen:

Date Revised 30.03.2024

published: Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.3390/ma17061386

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM370310845