Release Time:2019-10-10  Hits:

Indexed by: Journal Article

Date of Publication: 2019-08-01

Journal: CERAMICS INTERNATIONAL

Included Journals: EI、SCIE

Volume: 45

Issue: 11

Page Number: 14464-14468

ISSN: 0272-8842

Key Words: Porous ceramics; Composites; Biomimetics; Freeze casting; Mechanical properties; Microstructures

Abstract: Nacre consisting of aragonite layers and organic layers exhibits extraordinary strong and tough properties due to its hierarchical structure. Generally, nacre-like structure can be produced by freeze casting technique. However the waviness of aragonite layers of nacre is still not replicated in the existing freeze-cast materials. Here, a novel method is proposed to create the waviness in freeze-cast lamellar alumina scaffolds through a heat-treatment process of their green-bodies whose side-faces are glued to Teflon plates. The heat-treatment temperatures of 60 degrees C, 120 degrees C and 180 degrees C are used in the heat-treatment process, respectively. Lamellar composites with nacre-like waviness are obtained through infiltrating the alumina scaffolds with epoxy. The waviness heights and mechanical properties of the alumina-epoxy composites show a strong dependence on the heat-treatment temperature. When the heat-treatment temperature is 120 degrees C, the alumina-epoxy composites exhibit the optimal waviness heights and better comprehensive mechanical properties: relatively high flexural strength, flexural modulus, toughness and ultimate strain.