Premium
Fabrication and Property of Mullite Whiskers Frameworks with an Ultrahigh Porosity by Expandable Mesocarbon Microbeads
Author(s) -
Zeng DeJun,
Zhang YaMing,
Yang JianFeng,
Wang Bo,
Matsushita Junichi
Publication year - 2016
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/jace.14309
Subject(s) - whiskers , mullite , materials science , porosity , composite material , whisker , fabrication , phase (matter) , compressive strength , chemical engineering , ceramic , chemistry , medicine , alternative medicine , organic chemistry , pathology , engineering
Mullite whiskers frameworks with an ultrahigh porosity were fabricated by the vapor‐phase reaction of AlF 3 , Al 2 O 3 , and SiO 2 and adding expandable mesocarbon microbeads ( MCMB ) as a pore‐forming agent. A large volume expansion of 122% for MCMB due to its layered structure occurred during the formation of mullite whiskers, resulting in the expansion of samples and high porosities of 87.7%–98.2% at 50–90 wt% MCMB contents. Perfect whiskers and a lap‐joint structure formed due to the formation of mullites through the vapor‐phase reaction. A bimodal pore structure was achieved from the spaces of the whiskers framework and burning of the expanded MCMB . High compressive strengths of 1.7 to 5.4 MPa were obtained for the porous mullite at porosities of 94.2%–87.7%, which suggested a rigid structure; these strengths at the ultrahigh porosities are attributed to the merit of the framework with high strength whiskers and their strong bonding.