Publication detail

Restraining of calcium contamination in near-net shape alumina ceramics during slip casting

DRDLÍK, D. ROLEČEK, J. DRDLÍKOVÁ, K. SALAMON, D.

Original Title

Restraining of calcium contamination in near-net shape alumina ceramics during slip casting

English Title

Restraining of calcium contamination in near-net shape alumina ceramics during slip casting

Type

journal article in Web of Science

Language

en

Original Abstract

The traditional method for shaping ceramics is by slip casting on gypsum molds; however, its application for near-net shaping of ceramic components is limited due to contamination by calcium ions. The focus of this study is the modification of the mold to limit Ca2+ contamination and to maintain favorable sucking properties. Cement was added to a standard gypsum mold to suppress its erosion, and a decrease in the sucking rate was observed due to its reduced macroporosity. The highest values of green densities were obtained at gypsum/cement weight ratios of 90/10 and 70/30. The microstructure analysis showed that alumina blocks prepared from the molds containing higher quantities of cement (30 or 50 wt%) were resistant to abnormal grain growth caused by Ca2+ contamination from the gypsum. The gypsum/cement mixtures for making molds for slip casting significantly limit mold erosion due to a lower sucking rate and abnormal grain growth of the slip cast samples because of the decreased diffusivity of Ca2+ ions. Therefore, the present modification of the mold renders the slip casting method more suitable for the near-net shaping of ceramics.

English abstract

The traditional method for shaping ceramics is by slip casting on gypsum molds; however, its application for near-net shaping of ceramic components is limited due to contamination by calcium ions. The focus of this study is the modification of the mold to limit Ca2+ contamination and to maintain favorable sucking properties. Cement was added to a standard gypsum mold to suppress its erosion, and a decrease in the sucking rate was observed due to its reduced macroporosity. The highest values of green densities were obtained at gypsum/cement weight ratios of 90/10 and 70/30. The microstructure analysis showed that alumina blocks prepared from the molds containing higher quantities of cement (30 or 50 wt%) were resistant to abnormal grain growth caused by Ca2+ contamination from the gypsum. The gypsum/cement mixtures for making molds for slip casting significantly limit mold erosion due to a lower sucking rate and abnormal grain growth of the slip cast samples because of the decreased diffusivity of Ca2+ ions. Therefore, the present modification of the mold renders the slip casting method more suitable for the near-net shaping of ceramics.

Keywords

alumina; contamination; density; microstructure; slip casting

Released

04.06.2018

ISBN

1744-7402

Periodical

International Journal of Applied Ceramic Technology

Year of study

15

Number

6

State

US

Pages from

1559

Pages to

1566

Pages count

8

URL

Documents

BibTex


@article{BUT150352,
  author="Daniel {Drdlík} and Jakub {Roleček} and Katarina {Drdlíková} and David {Salamon}",
  title="Restraining of calcium contamination in near-net shape alumina ceramics during slip casting",
  annote="The traditional method for shaping ceramics is by slip casting on gypsum molds; however, its application for near-net shaping of ceramic components is limited due to contamination by calcium ions. The focus of this study is the modification of the mold to limit Ca2+ contamination and to maintain favorable sucking properties. Cement was added to a standard gypsum mold to suppress its erosion, and a decrease in the sucking rate was observed due to its reduced macroporosity. The highest values of green densities were obtained at gypsum/cement weight ratios of 90/10 and 70/30. The microstructure analysis showed that alumina blocks prepared from the molds containing higher quantities of cement (30 or 50 wt%) were resistant to abnormal grain growth caused by Ca2+ contamination from the gypsum. The gypsum/cement mixtures for making molds for slip casting significantly limit mold erosion due to a lower sucking rate and abnormal grain growth of the slip cast samples because of the decreased diffusivity of Ca2+ ions. Therefore, the present modification of the mold renders the slip casting method more suitable for the near-net shaping of ceramics.",
  chapter="150352",
  doi="10.1111/ijac.13042",
  howpublished="print",
  number="6",
  volume="15",
  year="2018",
  month="june",
  pages="1559--1566",
  type="journal article in Web of Science"
}