Infrared laser absorption and melting behaviour of nano-sized cerium dioxide: A laser heating study. Issue 2 (February 2021)

• Record Type: Journal Article
• Authors: Manara, D.; Popa, K.; Robba, D.; Fongaro, L.; Colle, J.-Y.; Bulgheroni, A.
• Is Part Of: Journal of the European Ceramic Society. Volume 41:Issue 2(2021)
• Page Start: 1384
• Page End: 1390
• Publication Date: 2021-02
• Subjects: Cerium dioxide -- Laser absorption -- Melting -- Nano-crystallites; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2020.09.026
• Languages: English
• ISSNs: 0955-2219

Abstract

Highlights: Study of cerium dioxide nano-crystallites under intense laser irradiation at 1064.5. Smaller CeO2 grains absorb laser radiation more promptly than larger grains do. The solidification temperature of nanometric crystallites is about 3012 K. Lower solidification temperatures are observed in micrometric crystallites. Abstract: The absorption of a 1064.5 nm Nd:YAG laser line and the consequent heating up to melting of nano-crystalline CeO2 has been studied in compressed air. The behaviour of crystallites ranging from 3.2 nm to 11 nm has been investigated and compared with micro-crystalline CeO2 . A transparent / opaque transition occurs in CeO2 at lower heating laser power density in smaller crystallite sizes. Also the melting behaviour is strongly dependent on the crystallite size. If one manages to directly melt nano-crystals by optimising the heating conditions under a suited oxygen overpressure, the resulting melt has been observed to solidify at the highest temperature so far reported for CeO2 (3012 K), about 250 K higher than the temperature most commonly registered under oxidising conditions (2750 K). This is attributable to the large specific surface of nano-crystals, resulting, under a high oxygen potential, in their higher stability with respect to oxygen losses.