Wear transitions in monolithic alumina and zirconia-alumina composites

2006 ◽

Vol 51 ◽

pp. 64-67

Author(s):

Jing Sun ◽

Lian Gao

Keyword(s):

Carbon Nanotubes ◽

Bending Strength ◽

Weight Percent ◽

Processing Route ◽

Matrix Composites ◽

Alumina Matrix ◽

Multi Walled Carbon Nanotubes ◽

Alumina Composites ◽

Walled Carbon Nanotubes ◽

Monolithic Alumina

In this paper, a colloidal processing route was adopted to disperse multi-walled carbon nanotubes (MWNTs) into alumina powders homogenously. Alumina matrix composites containing 0.1 to 2 weight percent of MWNTs were successfully fabricated by pressureless sintering. Also, 1wt% MWNTs-alumina composites were prepared by hot pressing for comparison. It was found that when the sample was sintered at 1450oC, the addition of 1wt% carbon nanotubes led to 10% increase in bending strength compared with monolithic alumina. The reinforcement mechanism was discussed based on the microstructure investigation. The broken nanotubes and pullout of MWNTs at interfaces are efficient in transferring the load from the alumina matrix to the nanotubes, leading to the improvement of the mechanical properties.

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Influence of Morphology of Silica-Alumina Composites on Their Activity for Hydrolytic Dehydrogenation of Ammonia Borane

Journal of the Japan Institute of Energy ◽

10.3775/jie.95.480 ◽

2016 ◽

Vol 95 (6) ◽

pp. 480-486 ◽

Cited By ~ 9

Author(s):

Naoki TOYAMA ◽

Shinobu OHKI ◽

Masataka TANSHO ◽

Tadashi SHIMIZU ◽

Tetsuo UMEGAKI ◽

...

Keyword(s):

Ammonia Borane ◽

Silica Alumina ◽

Alumina Composites

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The mesoporous silicate-alumina composites application as supports for bifunctional sulfide catalysts for n-hexadecane hydroconversion

Journal of Porous Materials ◽

10.1007/s10934-021-01097-x ◽

2021 ◽

Author(s):

N. A. Vinogradov ◽

A. P. Glotov ◽

A. A. Savinov ◽

A. V. Vutolkina ◽

V. A. Vinokurov ◽

...

Keyword(s):

Sulfide Catalysts ◽

Mesoporous Silicate ◽

Alumina Composites

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Mechanical Properties of Zirconia Toughened Alumina Composites with TZP Partially Nanostructured Sintered by Liquid Fase

Materials Science Forum ◽

10.4028/www.scientific.net/msf.591-593.436 ◽

2008 ◽

Vol 591-593 ◽

pp. 436-440

Author(s):

João Marcos K. Assis ◽

Francisco Piorino Neto ◽

Francisco Cristóvão Lourenço de Melo ◽

Maria do Carmo de Andrade Nono

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Weibull Modulus ◽

Bending Test ◽

Sintering Aid ◽

Zirconia Composites ◽

Alumina Composites ◽

Grain Size And Shape ◽

Zirconia Toughened Alumina ◽

Zirconia Powders

A comparative study between alumina added niobia ceramics and two alumina zirconia composites from nanostructured TZP (7% and 14% weight) was made. On this composites the zirconia were yttria stabilized and the alumina were submicron structured. As sintering aid a mixture of magnesia, niobia and talc were used on all samples. The sintering was performed at 1450 oC during 60 minutes. The characteristic grain size and shape of an alumina and zirconia powders, aggregates and agglomerates were characterized. The sintering ceramics were evaluated through hardness, fracture toughness and 4 point bending test. Weibull statistic was applied on the flexural results. Although the fracture toughness result from ZTA were lower, and seems to be affected by the liquid fase, the hardness and Weibull modulus were higher than alumina niobia. The grains size and the homogeneity of its distributions on the microstructure of this ceramics was correlated to these higher values. The results from these alumina zirconia composites showed a potential to apply as a ballistic armor material.

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