scholarly journals Alternative of bone china and porcelain as ceramic hand molds for rubber latex glove films formation via dipping process

2020 ◽  
Vol 59 (1) ◽  
pp. 523-537
Author(s):  
Chaturaphat Tharasana ◽  
Aniruj Wongaunjai ◽  
Puwitoo Sornsanee ◽  
Vichasharn Jitprarop ◽  
Nuchnapa Tangboriboon
Keyword(s):  
Thermal Expansion ◽  
Flexural Strength ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Mold Surface ◽  
Rubber Latex ◽  
Latex Glove ◽  
Bone China ◽  
Synthetic Rubber ◽  
Natural And Synthetic

AbstractIn general, the main compositions of porcelain and bone china composed of 54-65%wt silica (SiO2), 23-34% wt alumina (Al2O3) and 0.2-0.7%wt calcium oxide (CaO) suitable for preparation high quality ceramic products such as soft-hard porcelain products for teeth and bones, bioceramics, IC substrate and magneto-optoelectroceramics. The quality of ceramic hand mold is depended on raw material and its properties (pH, ionic strength, solid-liquid surface tension, particle size distribution, specific surface area, porosity, density, microstructure, weight ratio between solid and water, drying time, and firing temperatures). The suitable firing conditions for porcelain and bone china hand-mold preparation were firing at 1270°C for 10 h which resulted in superior working molds for making latex films from natural and synthetic rubber. The obtained fired porcelain hand molds at 1270°C for 10 h provided good chemical durability (10%NaOH, 5%HCl and 10%wtNaCl), low thermal expansion coefficient (5.8570 × 10−6 (°C−1)), good compressive (179.40 MPa) and good flexural strength (86 MPa). While thermal expansion coefficient, compressive and flexural strength of obtained fired bone china hand molds are equal to 6.9230 × 10−6 (°C−1), 128.40 and 73.70 MPa, respectively, good acid-base-salt resistance, a smooth mold surface, and easy hand mold fabrication. Both obtained porcelain and bone china hand molds are a low production cost, making them suitable for natural and synthetic rubber latex glove formation.

Crystallization Behavior and Performance of MgO-Al2O3-SiO2 Glass-Ceramics by Sintering

2010 ◽  
Vol 92 ◽  
pp. 65-71 ◽  
Author(s):  
Pei Xin Zhang ◽  
Li Gao ◽  
Qiu Hua Yuan ◽  
Hai Lin Peng ◽  
Xiang Zhong Ren ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Flexural Strength ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Crystallization Process ◽  
Glass Ceramics ◽  
X Ray Diffraction ◽  
Low Thermal Expansion ◽  
Main Crystalline Phase ◽  
And Performance

The glass-ceramics of MgO-Al2O3-SiO2 system were prepared by sintering technology. The crystallization process of MgO-Al2O3-SiO2 glass-ceramics was investigated with X-ray diffraction (XRD), scanning electron microscopy (SEM), and other techniques; the discussion of breaking strength, thermal expansion coefficient and relevant properties at different sintering temperatures was also presented. The results show that: (1) The main crystalline phase isα-cordierite at different sintering temperatures, and the samples show high flexural strength and low thermal expansion coefficient; (2) with the increase of sintering temperature, the content of crystal phase increases, while the thermal expansion coefficient decreases evidently, the flexural strength and tightness density rise up first, then go down.

The Influence of Nanosized Leucite on Dental Porcelain Properties

2007 ◽  
Vol 280-283 ◽  
pp. 1605-1608 ◽  
Author(s):  
Jin Ping Yang ◽  
Jian Qing Wu ◽  
Ping Gen Rao ◽  
Chong Fei Xin ◽  
Dong Dan Chen
Keyword(s):  
Thermal Expansion ◽  
Flexural Strength ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Sol Gel ◽  
Micro Structure ◽  
Dental Porcelain ◽  
Gel Method ◽  
Sol Gel Method

The influence of leucite on dental porcelain properties is investigated in this paper. The nanosized leucite powder prepared by sol-gel method was added into a low-fusing temperature frit to fabricate dental porcelain fused to metal. The porcelains with different leucite contents were sintered at the temperatures ranging from 780° to 900°C. The flexural strength and the thermal expansion coefficient (TEC) of the dental porcelain containing leucite particles are evaluated. The micro- structure and phases of the porcelain are characterized and the mechanism that nanosized leucite particles strengthening the porcelain is discussed.

Preparation Polyisoprene (NR) and Polyacrylonitrile Rubber Latex Glove Films by Dipping Ceramic Hand Molds Process and their Properties

2018 ◽  
Vol 382 ◽  
pp. 21-25 ◽  
Author(s):  
Puwitoo Sornsanee ◽  
Vichasharn Jitprarop ◽  
Nuchnapa Tangboriboon
Keyword(s):  
Tensile Strength ◽  
Natural Rubber ◽  
Natural Rubber Latex ◽  
Film Surface ◽  
Rubber Latex ◽  
Elongation At Break ◽  
Latex Glove ◽  
Bone China ◽  
Synthetic Rubber ◽  
High Flexibility

Both synthetic and natural rubber latex can be used to form rubber latex glove films for medical and dental applications. The objective in this research is to study the natural and synthetic rubber latex glove films formation by dipping process with the bone china ceramic hand molds for 5, 10, and 15 min. From the experimental, the obtained natural rubber latex glove films are good appearance and good physical-mechanical properties i.e. smooth film surface, light pale yellow color, soft, translucent, high tensile strength, high elongation at break, and high flexibility better than those of synthetic rubber latex glove films. When the dipping time of bone china hand mold into natural rubber latex compound increases effect to tensile strength, thickness, and elongation at break increase. Tensile strength, elongation at break, and tensile stress of natural rubber latex films dipped for 15 min are equal to 12.82 ± 1.19 MPa, 1090.91 ± 4.92%, and 39.23 ± 3.63 N, respectively.

Effect of the Cooling Ways on the Properties and Microstructure of ZrO2/ZrW2O8 Ceramic Composites

2016 ◽  
Vol 697 ◽  
pp. 381-385 ◽  
Author(s):  
Jin Ping Li ◽  
Cheng Yang ◽  
Song He Meng ◽  
Fa Jun Yi ◽  
Yu Han Li
Keyword(s):  
Thermal Expansion ◽  
Flexural Strength ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Chemical Properties ◽  
Ceramic Composites ◽  
Cold Isostatic Pressing ◽  
Thermal Expansion Coefficients ◽  
Lower Thermal Expansion ◽  
Physical And Chemical

ZrO2 has been widely used due to its good physical and chemical properties and the ZrO2/ZrW2O8 ceramic composites with adjustable thermal expansion coefficient can be prepared by mixing and sintering the ZrO2 and ZrW2O8 powders. In this paper, the ZrO2/ZrW2O8 ceramic composites have been prepared by mixing, cold isostatic pressing and atmospheric sintering, and then being cooled in air or in water. We focus on the effect of the cooling ways on the properties and microstructure of the ZrO2/ZrW2O8 ceramic composites. The results show that the relative density of all samples is more than 98%. For the in-situ method, the density and flexural strength of the samples cooled in air and in water are 98.1% and 98.4%, 112.96MPa and 45.23MPa, respectively. The ZrW2O8 content and thermal expansion coefficient of the samples cooled in the air are less and higher than those in the water, respectively. For the direct mixture method, the density and flexural strength of the samples cooled in air and in water are 98.9% and 99.3%, 195.99MPa and 58.71MPa, respectively. For the four groups of the composite samples, they behave better mechanical properties after cooled in air, and lower thermal expansion coefficients after cooled in water.

Synthesis of Bio-Glass Ceramics in Na2O-CaO-SiO2-P2O5 System with Fluoride Additives

2007 ◽  
Vol 124-126 ◽  
pp. 759-762 ◽  
Author(s):  
Sung Hwan Kim ◽  
Yae Sol Kim ◽  
Hee Gon Bang ◽  
Sang Yeup Park
Keyword(s):  
Mechanical Properties ◽  
Thermal Expansion ◽  
Flexural Strength ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Vickers Hardness ◽  
Sintering Temperature ◽  
Glass Composition ◽  
Glass Ceramics ◽  
Ceramic Composition

In this study, we intend to synthesize the new bio-glass composition with fluoride additions, such as CaF2 and MgF2, instead of Na2O in bio-glass ceramic composition based on 45S5 (46.1SiO2-26.9CaO-24.4Na2O-2.6P2O5, mol%). Also, we intend to increase the SiO2 content up to 50 mol% to enhance the mechanical properties. When B2O3 (4 mol%) was added as a Na2O substitution, thermal expansion coefficient was decreased at the sintering temperature (650~950 oC). Compared to the low flexural strength (57±3 MPa) and vickers hardness (4.6 GPa) of sintered bio-glass ceramics without fluoride and B2O3, bio-glass ceramics substituted with 10mol% MgF2 for Na2O showed more higher mechanical properties (flexural strength: 141±5 MPa, vickers hardness: 5.6 GPa). Thermal expansion coefficient of bio-glass ceramics with the ion substitutions (Ca2+, Mg2+ and B3+) was decreased from 16×10-6/oC to 9.4~10×10-6/oC (~400 oC).

scholarly journals Preparation of low-permittivity K2O–B2O3–SiO2–Al2O3 composites without the addition of glass

2019 ◽  
Vol 8 (1) ◽  
pp. 459-466 ◽  
Author(s):  
Yong Shang ◽  
Chaowei Zhong ◽  
Ruonan Jia ◽  
Huajing Xiong ◽  
Hao Li ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Flexural Strength ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
The Novel ◽  
X Ray Diffraction ◽  
Promising Candidate ◽  
Low Dielectric ◽  
Low Thermal Expansion ◽  
Low Permittivity

Abstract In the field of low temperature co-fired ceramic (LTCC), it remains a challenge to design the performance of LTCC with low permittivity less than 5. Here, the K2O– B2O3–SiO2–Al2O3 composites are prepared without the preparation of prior glass. Meanwhile, the factors of the CaO content on microstructure, phase structure and properties of the composites are considered systematically. The crystal structure measured by X-ray diffraction (XRD) shows that there are quartz and alumina as the crystal phases. The results reveals that the tailoring CaO content benefits sintering densification, low dielectric loss, great mechanical properties and low thermal expansion coefficient. As CaO content increases up to 2.8 wt%, the composites sintered at 850∘C have a dielectric constant of 4.94 and tanδ of 8 × 10−4 at 1 MHz, thermal expansion coefficient (CTE) of 8.5 ppm/∘C, and flexural strength of 150 MPa. As the mass fraction of CaO increases up to 3.2 wt%, the maximum flexural strength of 173MPa is achieved. The above study provides an effective approach for preparing the novel composites as a promising candidate for LTCC applications.

Effect of Aging pH Value on the Properties of Porous SiC Ceramics Produced through Coat-Mix Process

2012 ◽  
Vol 512-515 ◽  
pp. 770-774 ◽  
Author(s):  
Hui Yang ◽  
Hong Sheng Zhao ◽  
Zhong Guo Liu ◽  
Zi Qiang Li ◽  
Kai Hong Zhang
Keyword(s):  
Thermal Expansion ◽  
Flexural Strength ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Phenolic Resin ◽  
Bending Strength ◽  
Ph Value ◽  
Sic Ceramics ◽  
Porous Sic ◽  
Silicon Carbide Ceramics

The core-shell structure precursor powder was synthesized through coat-mix process, and a small amount of Al2O3, SiO2and Y2O3composite additives were added. Porous silicon carbide ceramics were produced after molding, carbonization and sintering, and the crystalline phase, weight loss, porosity, bending strength, and thermal expansion coefficient were measured. The effect of aging pH value of coat-mix process on the characterization of porous SiC ceramics had been analyzed. The results indicate that the crosslink degree and curing rate of the phenolic resin is adjusted by changing the aging pH value, and the coating effect in the coat-mix process is improved. Thereby, the flexural strength, thermal expansion coefficient, porosity and pore distribution of the porous SiC ceramics could be adjusted according to the application requirements. When the pH value ranges from 3 to 5 or higher than 7, the phenolic resin shows a lower crosslink degree and char yield, while the ceramics show a higher porosity and a lower thermal expansion coefficient; and the flexural strength decreases as the aging environmental pH value increases.

scholarly journals Out-of-Plane Thermal Expansion Coefficient and Biaxial Young’s Modulus of Sputtered ITO Thin Films

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 153
Author(s):  
Chuen-Lin Tien ◽  
Tsai-Wei Lin
Keyword(s):  
Thin Films ◽  
Thermal Expansion ◽  
Thermal Stress ◽  
Young’S Modulus ◽  
Thermal Expansion Coefficient ◽  
Expansion Coefficient ◽  
Young's Modulus ◽  
Heating Temperature ◽  
Glass Substrates ◽  
Ito Thin Films

This paper proposes a measuring apparatus and method for simultaneous determination of the thermal expansion coefficient and biaxial Young’s modulus of indium tin oxide (ITO) thin films. ITO thin films simultaneously coated on N-BK7 and S-TIM35 glass substrates were prepared by direct current (DC) magnetron sputtering deposition. The thermo-mechanical parameters of ITO thin films were investigated experimentally. Thermal stress in sputtered ITO films was evaluated by an improved Twyman–Green interferometer associated with wavelet transform at different temperatures. When the heating temperature increased from 30 °C to 100 °C, the tensile thermal stress of ITO thin films increased. The increase in substrate temperature led to the decrease of total residual stress deposited on two glass substrates. A linear relationship between the thermal stress and substrate heating temperature was found. The thermal expansion coefficient and biaxial Young’s modulus of the films were measured by the double substrate method. The results show that the out of plane thermal expansion coefficient and biaxial Young’s modulus of the ITO film were 5.81 × 10−6 °C−1 and 475 GPa.

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