Crack behaviour and mechanical properties of thermally treated kaolin based ceramics: The influence of pore generating agents

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389021%3A_____%2F20%3A00538536" target="_blank" >RIV/61389021:_____/20:00538536 - isvavai.cz</a>

Result on the web

<a href="https://www.sciencedirect.com/science/article/pii/S0169131720302635?via%3Dihub" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0169131720302635?via%3Dihub</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.clay.2020.105698" target="_blank" >10.1016/j.clay.2020.105698</a>

Result language

angličtina

Original language name

Crack behaviour and mechanical properties of thermally treated kaolin based ceramics: The influence of pore generating agents

Original language description

In this study, the crack behaviour of porous kaolin based ceramics was experimentally investigated. The samples (ceramic bodies) were fabricated with the inclusion of pore formers in determined proportions and subjected to heat treatment. Next, the apparent porosity of the samples was measured using the water immersion method. The values confirmed the increased porosity (up to 47%) for the samples with embedded pores. We speculated that the open pores on the surface of the samples which were quite evident, especially with styrofoam as pore formers, may also have penetrated through, hence the enhanced porosity values for the samples. Acoustic emission (AE) activity which reveals the formation of microcracks in the ceramics due to the different thermal expansion coefficients in the cooling stage was recorded for the samples. The first signals of AE counts appeared at 800 °C, where the compressive stresses between the different phases (particles with different coefficients of thermal expansion) led to an appearance of microcracks. By introducing porosity to the samples, the AE signals were less pronounced. This was evident for the samples with sawdust as pore formers, and it was inferred that in this sample, microcracking was suppressed. As a validation protocol for AE measurements, mechanical measurements on the produced samples were conducted through the indentation technique to obtain the fracture toughness of the samples. The results conformed to the observation made during AE measurements. The samples embedded with sawdust as porogens produced the highest fracture toughness of 4.77 MPa.m1/2 by reason of the suppression of microcracking after heat treatment.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

20501 - Materials engineering

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2020

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Applied Clay Science

ISSN

0169-1317

e-ISSN

—

Volume of the periodical

194

Issue of the periodical within the volume

September

Country of publishing house

NL - THE KINGDOM OF THE NETHERLANDS

Number of pages

6

Pages from-to

105698

UT code for WoS article

000546204800001

EID of the result in the Scopus database

2-s2.0-85085840274