Fabrication and properties of porous boron nitride/silicon oxynitride ceramic composites via gas pressure sintering

- SiAlON ceramics were produced from different starting Si3N4 powders including β-Si3N4 and α-Si3N4 powders and mixtures of these powders. Gas pressure sintering was used for sintering. After sintering, resultant fracture toughness values were correlated with microstructure and starting powders. By optimizing chemistry and process parameters; - SiAlON ceramics with reasonable fracture toughness can be produced from rather coarse β-Si3N4 powder. This could improve the economic viability of SiAlON ceramics since -Si3N4 powders are less costly.

Download Full-text

Luminescence properties of a green-emitting Eu2+-doped Sr-containing SiAlON phosphors by gas pressure sintering

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-015-2906-6 ◽

2015 ◽

Vol 26 (6) ◽

pp. 3805-3812 ◽

Cited By ~ 2

Author(s):

Chunlei Zhao ◽

Qian Ma ◽

Ronghui Liu ◽

Huibing Xu ◽

Hongqi Ye ◽

...

Keyword(s):

Gas Pressure ◽

Luminescence Properties ◽

Gas Pressure Sintering

Download Full-text

Influence of powder characteristics on gas pressure sintering of Si3N4

Journal of Materials Science ◽

10.1007/bf00551328 ◽

1988 ◽

Vol 23 (9) ◽

pp. 3413-3419 ◽

Cited By ~ 35

Author(s):

M. Mitomo ◽

N. Yang ◽

Y. Kishi ◽

Y. Bando

Keyword(s):

Gas Pressure ◽

Powder Characteristics ◽

Gas Pressure Sintering

Download Full-text

Strengthening Effect of In-Situ Dispersed Hexagonal Boron Nitride in Ceramic Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.317-318.163 ◽

2006 ◽

Vol 317-318 ◽

pp. 163-166

Author(s):

Guo Jun Zhang ◽

Hideki Kita ◽

Naoki Kondo ◽

Tatsuki Ohji

Keyword(s):

Grain Size ◽

Boron Nitride ◽

Hexagonal Boron Nitride ◽

High Strength ◽

Ceramic Composites ◽

Strengthening Effect ◽

Mechanical Shock ◽

Metallic Particles ◽

Reactive Hot Pressing

High strength particulate ceramic composites are in general reinforced by strong dispersoids, such as strong ceramic particles (SiC, TiB2, ZrO2, et al) and strong metallic particles (Mo, W, et al). In this work high strength ceramic composites with in-situ synthesized hexagonal boron nitride (h-BN) have been prepared and characterized. As an example, we manufactured mullite-BN composites by reactive hot pressing (RHP) using aluminum borates (9Al2O3·2B2O3 and 2Al2O3·B2O3) and silicon nitride as starting materials. The obtained material RHPed at 1800°C showed a strength of 540 MPa, which was 1.64 times higher than that of the monolithic mullite ceramics. TEM observation revealed that the composite had an isotropic microstructure with a fine mullite matrix grain size of less than 1 μm and a nano-sized h-BN platelets of about 200 nm in length and 60∼80 nm in thickness. The high strength was suggested to be from the reduced matrix grain size and the small toughening effect by the h-BN platelets. In addition, this kind of ceramic composite demonstrates low Young’s modulus that is beneficial to the thermal/mechanical shock resistance, and excellent machinability.

Download Full-text