Pressureless synthesis of fully dense and crack-free SiOC bulk ceramics via photo-crosslinking and pyrolysis of a polysiloxane

被引：131

作者：

Martinez-Crespiera, Sandra ^{[1
]}

Ionescu, Emanuel ^{[1
]}

Kleebe, Hans-Joachim ^{[2
]}

Riedel, Ralf ^{[1
]}

机构：

[1] Tech Univ Darmstadt, Inst Mat Wissensch, D-64287 Darmstadt, Germany

[2] Tech Univ Darmstadt, Inst Angew Geowissensch, D-64287 Darmstadt, Germany

来源：

JOURNAL OF THE EUROPEAN CERAMIC SOCIETY | 2011年 / 31卷 / 05期

关键词：

Carbon; Electrical conductivity; Glass ceramics; Polymer derived ceramics (PDCs); C-N CERAMICS; MECHANICAL CHARACTERIZATION; MICROSTRUCTURE EVOLUTION; PART II; SPECTROSCOPY; FABRICATION; GRAPHITE;

D O I：

10.1016/j.jeurceramsoc.2010.11.019

中图分类号：

TQ174 [陶瓷工业]; TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

This paper presents the pressureless preparation of fully dense and crack-free SiOC ceramics via direct photo-crosslinking and pyrolysis of a polysiloxane. Elemental analysis revealed the presence of high levels of carbon in the SiOC ceramics. Thus, the samples showed the highest content (78-86 mol%) of segregated "free" carbon reported so far. XRD investigations indicated that the materials prepared at 1100 degrees C were X-ray amorphous, whereas the sample prepared at 1400 degrees C contained a turbostratic graphite-like phase and silicon carbide as crystalline phases, as additionally confirmed by TEM and Raman spectroscopy. Vickers hardness was measured to be 5.5-8.6 GPa. The dc resistivity of the prepared material at 1100 degrees C was 0.35 Omega m, whereas the ceramic pyrolyzed at 1400 degrees C showed a value of 0.14 Omega m; both values are much lower than those of other known SiOC materials. This latter feature was attributed to the presence of a percolating carbon network in the ceramic. (C) 2010 Elsevier Ltd. All rights reserved.

引用

页码：913 / 919

页数：7