Ag diffusion inhibition and enhanced flexural strength in low temperature co-fired CaO-Al2O3-B2O3-SiO2 glasses

Low temperature sintered MgO-Al2O3-SiO2 glass-ceramic with high mechanical and low thermal expansion was prepared for package. The remarkable influence of B2O3 addition on the electrical, mechanical, and thermal properties was fully investigated. A small amount of B2O3 promoted the sintering process and improved the densification of MAS. The kinetics via Kissinger method indicated that an appropriate B2O3 content decreased the activation energy and helped the occurrence of crystallization. Due to the increase of crystallinity and indialite phase, B2O3 addition significantly enhanced flexural strength and Young’s modulus. MAS doped with 3wt% B2O3 can be sintered at 900 °C and obtained good properties: σ = 229 MPa, φ = 86 GPa, α = 1.66×10-6 /°C, εr = 5.29, and tanδ = 5.9×10-4.

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Ceramization Mechanism of Ceramizable Silicone Rubber Composites with Nano Silica at Low Temperature

Materials ◽

10.3390/ma13173708 ◽

2020 ◽

Vol 13 (17) ◽

pp. 3708

Author(s):

Penghu Li ◽

Haiyun Jin ◽

Shichao Wei ◽

Huaidong Liu ◽

Naikui Gao ◽

...

Keyword(s):

Low Temperature ◽

Flexural Strength ◽

Silicone Rubber ◽

Glass Frit ◽

Nano Silica ◽

Linear Contraction ◽

Ceramic Phase ◽

Ceramic Samples ◽

Different Temperatures ◽

Similar Materials

Ceramizable composite is a kind of polymer matrix composite that can turn into ceramic material at a high temperature. It can be used for the ceramic insulation of a metal conductor because of its processability. However, poor low-temperature ceramization performance is a problem of ceramizable composites. In this paper, ceramizable composites were prepared by using silicone rubber as a matrix. Ceramic samples were sintered at different temperatures no more than 1000 °C, according to thermogravimetric analysis results of the composites. The linear contraction and flexural strength of the ceramics were measured. The microstructure and crystalline phase of ceramics were analyzed using scanning electron microscope (SEM) and X-ray diffraction (XRD). The results show that the composites turned into ceramics at 800 °C, and a new crystal and continuous microstructure formed in the samples. The flexural strength of ceramics was 46.76 MPa, which was more than twice that of similar materials reported in other research sintered at 1000 °C. The maximum flexural strength was 54.56 MPa, when the sintering temperature was no more than 1000 °C. Moreover, glass frit and nano silica played important roles in the formation of the ceramic phase in this research. A proper content of nano silica could increase the strength of the ceramic samples.

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Influences of Aging History on Low Temperature Performance of Asphalt Concrete

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.385-387.493 ◽

2008 ◽

Vol 385-387 ◽

pp. 493-496 ◽

Cited By ~ 1

Author(s):

Shao Peng Wu ◽

Guo Jun Zhu ◽

Ling Pang ◽

Cong Hui Liu

Keyword(s):

Low Temperature ◽

Flexural Strength ◽

Asphalt Concrete ◽

Tensile Strain ◽

Natural Aging ◽

Bending Stiffness ◽

Bending Test ◽

Stiffness Modulus ◽

Stone Mastic Asphalt ◽

High And Low Temperatures

According to three-point bending test, this paper explores the influence of low temperature on the flexural strength, the tensile strain and bending stiffness modulus of the aged Stone Mastic Asphalt (SMA-13) concrete. The asphalt mixtures are aged according to the short-term aging (at 135°C, 4 hours), and long-term aging (asphalt concrete at 85°C, 120 hours) and natural aging (3 months, 6 months and 9 months). The result shows that, with the same loading rate, the tensile strain of specimens at -30°C are smaller than those at -10°C; but when temperature is certain, the tensile strain of specimens lager than those of aged specimens. The longer the aging time lasts, the more flexural strength differences between high and low temperatures can be found. A pretty well index variation can be found between the tensile strain and temperature. The same trend also appears between the bending stiffness modulus and temperature of SMA-13 asphalt concrete.

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Effect of pores on flexural strength of roofing tiles at low temperature

British Ceramic Transactions ◽

10.1179/096797803225001623 ◽

2003 ◽

Vol 102 (3) ◽

pp. 133-137 ◽

Cited By ~ 2

Author(s):

H. S. Kim ◽

J. H. Kim ◽

K. Ikeda

Keyword(s):

Low Temperature ◽

Flexural Strength

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Comparison of the Low Temperature Degradation Properties of Two Y-TZP Ceramics for Dental Applications

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.492.107 ◽

2011 ◽

Vol 492 ◽

pp. 107-111 ◽

Cited By ~ 1

Author(s):

Yuan Fu Yi ◽

Ning Wen ◽

Xiao Ling Wang ◽

Long Quan Shao ◽

Chen Wang

Keyword(s):

Low Temperature ◽

Flexural Strength ◽

Monoclinic Phase ◽

Surface Microstructure ◽

Force Microscopy ◽

Dental Application ◽

Before And After ◽

Dental Applications ◽

Degradation Properties

The purpose of this study was to investigate the influence of in vitro low-temperature degradation (LTD) treatments on the structural stability and mechanical properties of two commercial Y-TZP ceramics candidate for dental application. TZ-3YS and TZ-3YS-E powder were chosen because of there minor differences of chemical composition. The two powders were compacted at 200MPa using cold isostatic pressure, and densely sintered at 1500°C and 1450°C for 2hr respectively. Two methods of in vitro LTD treatments were performed, the first is to autoclave specimens in steam at 134°C, 2bar, for 1 to 5hr; the second is to immerse specimens into 4% acetic acid at 80°C for 168 hr. XRD was used to identify the crystal phases, flexural strength were tested according to ISO 6872 standard, surface microstructure was evaluated by Atomic Force Microscopy (AFM). Results show that the relative content of monoclinic phase was increasing with the prolonged aging time, the TZ-3YS was more sensitive to LTD compared with TZ-3YS-E. LTD tests did not necessary reduce the flexural strength of Y-TZP ceramics, the nucleation and growth of monoclinic phase were detected by AFM, and the surface microstructure induced by LTD was not identical between the two Y-TZP ceramics. AFM was a sensitive method to evaluate the transformation of Y-TZP ceramics. To choose appropriate Y-TZP powder for dental application, it is mandatory to examine the microstructure before and after LTD.

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Low Temperature Fabrication and Characterization of Porous SiC Ceramics Using Polycarbosilane as Binder

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.1090 ◽

2007 ◽

Vol 336-338 ◽

pp. 1090-1092 ◽

Cited By ~ 3

Author(s):

Qing Song Ma ◽

Xiao Dong Yu

Keyword(s):

Particle Size ◽

Low Temperature ◽

Fracture Surface ◽

Flexural Strength ◽

Sic Ceramics ◽

Fabrication And Characterization ◽

Porous Sic

Polycarbosilane (PCS) and SiC powders, in which PCS acted as binder, were adopted as starting materials to fabricate porous SiC ceramics. During pyrolysis, PCS experienced an organicinorganic transformation and bonded SiC powders at a low temperature of 1273K. The flexural strength of porous SiC ceramics increased with increasing PCS content and shaping pressure, while the porosity decreased with increasing the PCS content, shaping pressure and particle size of SiC powders. The fracture surface of porous SiC ceramics was observed.

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Influence of Low Temperature Aging on the Flexural Strength of Y-TZP Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.512-515.1756 ◽

2012 ◽

Vol 512-515 ◽

pp. 1756-1760 ◽

Cited By ~ 1

Author(s):

Chen Wang ◽

Li Min Dong ◽

Yuan Fu Yi ◽

Ning Wen ◽

Qing Feng Zan ◽

...

Keyword(s):

Phase Transition ◽

Phase Transformation ◽

Low Temperature ◽

Flexural Strength ◽

Monoclinic Phase ◽

Accelerated Aging ◽

Strength Increase ◽

Low Temperature Aging ◽

Temperature Aging

Low temperature aging (LTD) is an important factor of Y-TZP ceramic as artificial joint femoral head and dental restorative materials in vivo for long-term application. In this paper, the accelerated aging experiments on Y-TZP ceramics were conducted. The t-m phase transition is occurring from the surface to the inside during low temperature aging of Y-TZP ceramics. As content of phase transformation increases, thickness of phase transformation layer increases. While the content of surface monoclinic phase is less, the volume expansion and surface stress caused by phase transformation can make cracks and holes shrink or even close, then the flexural strength increase. As a large number of surface monoclinic phase was generated, due to there are a lot of microscopic defects in the phase transition layer, crystals loose, strength of grain boundary lower than that of not aging area and phase transformation layers fracture in the intergranular mode, that damages the flexural strength. Therefore, the flexural strength increase firstly and then decrease with the increase of surface monoclinic content.

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