title: Unidirectional freezing of ceramic suspensions: in situ X-ray investigation of the effects of additives.
abstract: Using in situ X-ray radiography, we investigated unidirectional freezing of titanium dioxide suspensions. We showed how processing additives, which are generally used for ice-templating, strongly modified freezing dynamics during the solidification process. We observed and identified different freezing regimes by varying the amount of dispersant, binder, or poly(ethylene glycol) (PEG). We demonstrated that because each regime corresponds to a given final structure understanding the particle motion and redistribution at the ice-front level was essential. We also examined the transition from a random particles-entrapment regime to a well-defined lamellar regime and proposed and discussed two mechanisms by which additives might affect the solidification process.
authors.affiliation: Materials Sciences Division Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Delattre
authors.forename: Hao
authors.initials: H
authors.lastname: Bai
authors.forename: Robert O
authors.initials: RO
authors.lastname: Ritchie
authors.forename: Joël
authors.initials: J
authors.lastname: De Coninck
authors.forename: Antoni P
authors.initials: AP
authors.lastname: Tomsia