Effect of ZrO2 content on the microstructure and flexural strength of Al2O3–ZrO2 composites with the stored failure energy-fragmentation relations

Mullite–zirconia composites were synthesized through reaction sintering Algerian kaolin, α-Al2O3, and ZrO2. Phases present and their transformations were characterized using x-ray diffraction. Quantitative phase analysis was performed following the Rietveld method. Hardness and fracture toughness were measured by Vickers indentation. The flexural strength was measured using a Universal Testing Machine. It was found that the microstructure of samples sintered for 2 hours at 1600°C was composed of mullite grains which have whiskers’ shape and ZrO2 particles. In the composite containing 16 wt.% ZrO2, the ratio of tetragonal zirconia transformed to monoclinic zirconia was relatively small and did not exceed 18%. However, in the composite containing 32 wt.% ZrO2 around 75% of the tetragonal structure changed to monoclinic structure. Also, it was found that the increase of ZrO2 content from 0 to 32 wt.% decreased the microhardness of the composites from 14 to 10.8 GPa. However, the increase of ZrO2 content from 0 to 24wt.% increased the flexural strength of the composites from 142 to 390 MPa then decreased it with further increase of ZrO2 content. The fracture toughness increased from 1.8 to 2.9 MPa.m1/2 with the increase of ZrO2 content from 0 to 32 wt.%; and the rate of the increase decreased at higher fractions of ZrO2 content. The average linear coefficient of thermal expansion (within the range 50 to 1450°C) for samples containing 0 and 16 wt.% ZrO2 sintered at 1600°C for 2 hours was 4.7 x10-6 K-1 and 5.2 x 10-6 K-1 respectively.

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Relation between abrasion resistance and flexural strength of high volume fly ash concrete

Materials and Structures ◽

10.1617/13827 ◽

2002 ◽

Vol 35 (248) ◽

pp. 257-260 ◽

Cited By ~ 10

Author(s):

C. D. Atis

Keyword(s):

Fly Ash ◽

Flexural Strength ◽

Abrasion Resistance ◽

High Volume ◽

Fly Ash Concrete ◽

High Volume Fly Ash

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The low temperature properties of conventional and modified asphalt binders evaluated by the failure energy and secant modulus from direct tension tests

Materials and Structures ◽

10.1617/14106 ◽

2004 ◽

Vol 38 (275) ◽

pp. 137-143 ◽

Cited By ~ 1

Author(s):

S. Ho

Keyword(s):

Low Temperature ◽

Asphalt Binders ◽

Secant Modulus ◽

Direct Tension ◽

Modified Asphalt ◽

Failure Energy ◽

Tension Tests

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SIFAT FISIS MEKANIS BAMBU LAPIS SEBAGAI BAHAN BAKU PRODUK INTERIOR

Jurnal Riset Industri Hasil Hutan ◽

10.24111/jrihh.v3i1.1183 ◽

2011 ◽

Vol 3 (1) ◽

pp. 15

Author(s):

Arhamsyah Arhamsyah

Keyword(s):

Flexural Strength ◽

Water Content ◽

Raw Material ◽

Technical Aspects ◽

Material Layer ◽

Weight Variation

Research on the utilization of bamboo as a raw material layer interior products have been made. This research aims to determine the nature of plybamboo in terms of technical aspects / processes of manufacture, physical and mechanical, the influence of weight variation labur adhesive, adhesive types and kinds of bamboo products plybamboo.This type of bamboo used is sweet bamboo (Gigantochloa atter Kurz) and bamboo lear (Gigantochloa apus Kurz).The adhesive used was adhesive Polyvinil Acetat (PVAc) and Chloroprene with adhesive labur weight each - each 150 gr/m2, 200 gr/m2 and 250 gr/m2. The parameters tested were water content, density, flexural strength of dry and delamination.The results showed that the treatment using bamboo material with adhesive Chloroprene sweet heavy labur 250 gr/m2 produce the best plybamboo.Keywords: bamboo, glue, physical, mechanical

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