TY - JOUR

T1 - The effect of liquid phase chemistry on the densification and strength of cold sintered ZnO

AU - Jabr, Abdullah

AU - Fanghanel, Julian

AU - Zongming, Fan

AU - Bermejo, Raul

AU - Randall, Clive A.

N1 - Publisher Copyright: © 2022 The Authors

PY - 2023

Y1 - 2023

N2 - Cold sintering is a chemo-mechanical densification process which allows densification of ceramics at low temperatures below 300 °C. This substantial reduction in the sintering temperature is enabled by an externally applied pressure and a compatible transient liquid phase. In this paper, ZnO is cold sintered using various commercial organic acids: formic, acetic and citric acid. The effect of these different transient phases on densification, microstructural evolution and mechanical response is investigated. Fourier transform infrared spectroscopy, thermogravimetric analyses and transmission electron microscopy were conducted to explain the chemical interactions in the cold sintering process. High relative densities (∼ 96 %) were achieved by formic and acetic acid, whereas poor densification was obtained for citric acid (< 80 %), despite the higher expected solubility of zinc oxide. The higher biaxial strength found in samples sintered with formic acid compared to acetic acid (i.e. ∼90 MPa vs. ∼40 MPa) is discussed supported by fractographic analyses.

AB - Cold sintering is a chemo-mechanical densification process which allows densification of ceramics at low temperatures below 300 °C. This substantial reduction in the sintering temperature is enabled by an externally applied pressure and a compatible transient liquid phase. In this paper, ZnO is cold sintered using various commercial organic acids: formic, acetic and citric acid. The effect of these different transient phases on densification, microstructural evolution and mechanical response is investigated. Fourier transform infrared spectroscopy, thermogravimetric analyses and transmission electron microscopy were conducted to explain the chemical interactions in the cold sintering process. High relative densities (∼ 96 %) were achieved by formic and acetic acid, whereas poor densification was obtained for citric acid (< 80 %), despite the higher expected solubility of zinc oxide. The higher biaxial strength found in samples sintered with formic acid compared to acetic acid (i.e. ∼90 MPa vs. ∼40 MPa) is discussed supported by fractographic analyses.

UR - http://www.scopus.com/inward/record.url?scp=85143863596&partnerID=8YFLogxK

U2 - 10.1016/j.jeurceramsoc.2022.11.071

DO - 10.1016/j.jeurceramsoc.2022.11.071

M3 - Article

VL - 43.2023

SP - 1531

EP - 1541

JO - Journal of the European Ceramic Society

JF - Journal of the European Ceramic Society

SN - 0955-2219

IS - 4

ER -