Title: Improvement of sinterability of KNN ceramics by mechanochemical activation-assisted process

Authors: Jae-Ho Jeon; Hyun Ae Cha

Addresses: Functional-Nano Powder Research Department, Korea Institute of Materials Science, Changwon, 642-831, Korea ' Functional-Nano Powder Research Department, Korea Institute of Materials Science, Changwon, 642-831, Korea

Abstract: In order to enhance the sintered density of K0.5Na0.5NbO3 [KNN] ceramics by using fine KNN powders, mechanochemical activation-assisted process was applied for the synthesis of KNN powders. Shaker milling of K2CO3-Na2CO3-Nb2O5 raw powders mixture for 30 min could decrease the temperature of the subsequent calcination from 800-850°C of the conventional solid-state reaction to 500°C. This novel process produced KNN powders with crystallites of 50-100 nm in size. The relative density of sintered KNN prepared by mechanochemical activation-assisted process was 95.7%, which was about 2% higher than that of sintered KNN prepared by the conventional solid-state reaction process. Mechanochemical activation-assisted process also improved the P-E property of sintered KNN ceramics.

Keywords: piezoelectrics; lead-free; K0.5Na0.5NbO3; mechanochemical activation; sintered density; P-E hysteresis; sinterability; KNN ceramics; potassium sodium niobate.

DOI: 10.1504/IJMPT.2015.072256

International Journal of Materials and Product Technology, 2015 Vol.51 No.3, pp.310 - 320

Received: 08 Aug 2014
Accepted: 28 May 2015

Published online: 06 Oct 2015 *

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