Internal friction at crack tip of soda-lime silicate glass

Role of graphene in enhancing indentation and scratch properties of soda lime silicate glass

Silica sand from Kandal province, Cambodia and Tapah Perak, Malaysia was grounded into an average micron size of 128.12 and 132.68µm. Both sands were characterized by X-ray fluorescence (XRF), X-ray Diffraction, particle Size Analysis, Differential Thermal Analysis and Thermogravimetric Analysis (DTA/TGA). Malaysian silica sand was designated SDMTP and Cambodian Silica sand as SDCK. From theanalysis, XRF showed that the major impurities in SDMTP were Al2O3, K2O and TiO2. On the other hand, SDCK had impurities of Al2O3,K2O and Na2O. DTA results from SDMTP and SDCK showedthere is an endothermic peak occurring at 572°C which can be attributed to β-quartz transformation into α-quartz. TGA for SDMTP showed that maximum weight lost was at 441°C with a weight percent (wt%) change of 0.48%. The TGA for SDCK showed a wt% change of 1.298% at temperature of 1000°C. From XRD analysis, the main phase of SDCK and SDMTP were quartz. The impurities of both sands play an important role in determining the optical and mechanical properties of the soda lime silicate (SLS) glass formed. Particle size of silica sand affects the mechanical properties such as compression, hardness, and transmittance of SLS glass. The smaller particle size would be ideal choice for glassmaking. Melting temperature, soaking time, and melt accelerant can also affect the mechanical properties of SLS glass. The best result obtained for Vickers hardness in this study was the SLS glass sample designated as Run No 12 with a value of 525.02 kg.mm-2. It had a particle size range from 500-600µm, a furnace soaking time of 4 hours at a melting temperature of 1500°C with 1.0 wt% of Sodium Chloride (NaCl) as meltingaccelerant. On the other hand, the highest compressive strength of 356.22 MPa was found in sample designated as Run No 1. It had a particle size range from 75-1800µm, a soaking time of 5 hours at a melting temperature of 1550°C with 0.5 wt% of NaCl. Lastly,the highest UV-VIS transmittance at 520 nm was obtained from sample designated as Run No 5 within the value of 84.26 %Transmittance (T). It had a particle size range of 75-1800µm, soaking time of 3 hours at a melting temperature of 1550°C with 1.5 wt% of NaCl. .

Quasistatic nature of subsurface densification of soda lime silicate glass under nano- and Vickers indentation

Ni/Cu co-doped in soda lime silicate (SLS) glasses were prepared by using normal melt quenchingtechnique at 1200oC for 3 h, and annealed at 500 oC for 3 h. The current composition was prepared based on theproposed ratio: (64.98-x)SiO2: 10CaO: 25Na2O: 0.02NiO: xCuO where x=0.0, 0.1, 0.2, 0.3, 0.4 and 0.5 mol%.The physical and optical properties of Ni/Cu co-doped in SLS glasses such as density, molar volume, refractiveindex and optical absorption were measured and discussed. The optical absorption spectrum of Ni/Cu co-dopedin SLS glasses measured at room temperature in the wavelength region 200–1100 nm were presented.

Co/Cr co-doped in soda lime silicate (SLS) glasses were prepared by using normal melt quenching technique. The current composition was prepared based on the proposed ratio: (64.9-x)SiO2: 10CaO: 25Na2O: 0.1CuO: xCoO where x=0.00, 0.01, 0.02, 0.03, 0.04 and 0.05 mol% were prepared at 1200°C for 3 h, and annealed at 500 °C for 3 h. The physical and optical properties of Co/Cr co-doped in SLS glasses were investigated such as density, molar volume, refractive index and optical absorption were discussed and measured. The optical absorption spectrum of Co/Cr co-doped in SLS glasses measured at room temperature in the wavelength region 200–1100 nm were presented.

Architectural soda-lime silicate glass (SLS) is increasingly taking on complex shapes that require more detailed numerical analysis. Glass modeling is a thoroughly described topic with validated constitutive models. However, these models require a number of precise material parameters for SLS glass, and these are very sensitive to changes in glass composition. The currently available information is based on SLS glass tested in the late 1990s. As a result, most current publications are based on the above data. The object of this work was to analyze the available sources and update the information on selected key parameters for modeling. Using the currently utilized SLS glass in construction, the coefficient of thermal expansion (CTE), glass transition temperature, and the Young’s modulus have been experimentally investigated. The updated material parameters will allow for more accurate modeling of the SLS glass currently used in construction, and in consequence will make the prototyping process for glass with complex geometries possible to be transferred from the production stage to the design stage, resulting in shorter production times.

In the present work, Fe/Co co-doped in soda lime silicate (SLS) glasses were prepared by using normal melt quenching technique. The physical and optical properties of Fe/Co co-doped in SLS glasses such as density, molar volume, refractive index and optical absorption were investigated. The density and refractive index of the samples increases with increasing concentration of CoO. The molar volume values were found to decrease due to the decreasing of number of non-bridging oxygens (NBOs), which will lead to the close packing of atoms. The optical absorption spectrum of Fe/Co co-doped in SLS glasses measured at room temperature in the wavelength region 200–1100 nm. The absorption peak occurred at 380 537 595and 650 nm. In the wavelength at 385 nm has been assigned to the 6A1g(S) → 4T1g(P) transitions of Fe3+. From the Tanabe–Sugano energy level diagram given for d5 configuration, the bands observed at 385 nm have been assigned to the 6A1g(S) → 4T1g(P) transitions. The observed band positions are characteristic of Fe3+ ions in the distorted octahedral environment. In the wavelength at 537 595 and 650 nm have been assigned to 4T1g(F) → 2T1g (H), 4A2(4F) → 4T1 (4P) and 2T2 → 2T transition of Co2+ ions of pure tetrahedral coordinated Co2+ ions in soda lime silicate glasses.

Can polymer-infiltrated florapatite glass ceramic produced from waste materials, such as clam shell and soda lime silicate glass, be used in prosthetic rehabilitation? The purpose of this study is to investigate the effect of Si/Ca ratio on the mechanical properties of Nb-Bi-Ce doped polymer-infiltrated fluorapatite ceramic networks (PICNs) produced from clam shell (CS) and soda lime silicate (SLS) glass by conventional melt-quench technique, used as a dental ceramic. PICNs comprising Si/Ca at four different weight percentage ratios: 1.27% (PICN-1), 2.15% (PICN-2), 4.12% (PICN-3) and 12.6% (PICN-4) were prepared (n=10). The powder mixtures in four different ratios were compressed in a rectangular prism shaped mold and subjected to equal pressure from all sides in a cold isostatic press, followed by heat treatment at 750C for 3 h. Then complete vacuum infiltration was done with a polymer mixture then low temperature firing was applied leading to the formation of the PICNs. Wear behavior and 3-point bending properties were evaluated and specimens were analyzed using scanning electron microscopy (SEM). The friction and wear properties were determined by means of a pin-on-disk tribotester. Since the flexural strength test did not show normal distribution, Kruskal Wallis test was performed in independent groups, p[0.05. There is a significant difference of flexural strength values between the groups (p=0.032), it was determined that the difference was between the PICN-1 and PICN-4 groups (p=0.037). In the analysis of wear scar, abrasion grooves were also observed. The results of this study showed that high Ca and Si content in CS and SLS glass, respectively, encourages the use of waste materials in the production of PICNs intended to be used in prosthetic rehabilitation. The composition of PICNs produced from waste materials affected flexural strength and wear behavior. Increasing the Si/Ca ratio was found to support the mechanical properties of experimental PICN and that experimental PICNs can be considered as high potential candidates for dental applications.

Thermally stimulated depolarization currents (TSDC) technique was used to monitor (in the range 100-620 K) the dielectric relaxations of (1) silica glasses of different origin and impurity contents (mainly Al and OH) and (2) soda-lime silicate (SLS) glasses, in which K/sup +/ and Ag/sup +/ were also substituted for Na/sup +/. In the SLS glasses three TSDC bands appear at temperatures lower than the main band of SiO/sub 2/ specimens: the position of two peaks depends on the nature of the monovalent ion. The polarization phenomena were larger in SLS than in SiO/sub 2/ glasses. The peak position and amplitudes were studied as a function of the polarization field, temperature and time. The origin of the relaxations is discussed.

The first attempt to produce a glass ceramic from waste material was reported as early as the 1960s and involved use of several types of slag of ferrous and nonferrous metallurgy, ash, and waste from the mining and chemical industries. Willemite (Zn2SiO4), which is a good host for rare earths to be used in telecommunications, has been produced by different methods from pure materials. However, there is a lack of research on preparation of willemite using waste materials. To date, most research has been carried out on soda lime silicate (SLS) glass doped with different ingredients and rare earths, but little research has been carried out on willemite-based glass ceramics prepared using waste material and doped with erbium oxide (Er2O3). However, use of waste materials, such as SLS glass, as a main source for producing silicate will be economical, inexpensive, and helpful for reducing the aggregation of waste materials in landfills. The main objective of this study is to determine the effects of addition of erbium oxide (Er2O3) on the physical and optical properties of willemite-based glass ceramic sintered at different temperatures.

The purpose of this study is to investigate the effect of spent bleach earth (SBE) loading on the properties of green glass ceramic (GGC) composite. GGC was prepared using SBE and recycled soda lime silicate (SLS) glass. SLS glass was crushed then sieved to approximately 45µm. These GGC composites were formed with different weight fraction of SBE loading (40, 45 and 55 wt.%) by uniaxial dry pressing and sintered at different sintering temperature (700 °C, 750 °C and 850 °C). The sintering temperatures were selected based on Tg of the glass which is around 416 °C. The GGC specimens were analyzed in terms of its physical properties (density, water absorption and porosity), phase presence (X-Ray diffraction) and sintered microstructure (scanning electron microscopy). X-Ray diffraction pattern indicated that cristobalite, quartz and wallastonite phases were formed during sintering. It was found that the GGC with 45 wt.% of SBE loading sintered at 850 °C produced minimum water absorption which was 4.01% accompanied by density of 2.12 g/cm3 and a porosity of 8.49%. This shows that GGC composite produced with considerable higher amount of waste loading able to obtain acceptable physical durability.

An apatite-mullite glass ceramics composition derived from clam shell (CS) and soda lime silicate (SLS) glass has been fabricated from a heat treatment process of composition [xCaF2·(45−x)SLS·15CS·20Al2O3·20P2O5], where x is 5, 10, 15 and 20 (wt. %). The result concluded that the Ca and Si elements were found in the CS and SLS glass respectively as a major weight composition, thereby promoting the use of waste materials in the manufacture of glass ceramic samples. Besides, the CaF2 addition lowers the glass transition temperature (Tg) and crystallisation temperature (Tc) of the glass composition. The density and percentage of the linear shrinkage of the samples differs with the addition of CaF2 and various heat treatment temperatures. For the structural properties’ analysis, the formation of fluorapatite with a needle-like microstructure and mullite phase was enhanced with a higher CaF2 content, while the growth of the anorthite phase was observed to occur at a higher heat treatment temperature. Generally, the addition of ahigh CaF2 content with the help of heat treatment in apatitemullite glass ceramics composition greatly promotes the crystallisation of the fluorapatite phase, which is crucial for denture glass ceramics.

Soda-lime silicate (SLS) glass was strengthened by ion exchange for application of thin and lightweight bulletproof windows.The optimal conditions for ion exchanged SLS glass (thickness of 3 and 10 mm) at 480 o C were 10 and 17 min, respectively.The Vickers hardness values of the strengthened SLS glass samples with thicknesses of 3 and 10 mm were 5.9 ± 0.22 and 6.7 ± 0.17 GPa, respectively, which values were about 22% higher than those of parent SLS glass.By laminating a multilayer defense film and polycarbonate sheet with ion exchanged SLS glass, we were able to make a thin and lightweight bulletproof window (24.25 mm, 4.57 kg, 50.06 kg/m 2 , V 50 901.8m/s).As a result, the thickness of the bulletproof window was decreased by about 39% from 40 to 24.25 mm.The light transmittance in the visible range satisfied the standard (over 76%) for bulletproof windows.

A study on the effect of sintering temperature to the physical and structural of Alumino-Silicate-Fluoride (ASF) glass ceramics fabricated from clam shell (CS) and soda lime silicate (SLS) glass is conducted through conventional melt-quench technique. ASF glass ceramics composition with 25SLS-20CS-20P2O5-20Al2O3-15CaF2 by weight percentage is analysed by using Energy X-ray (EDX), density (ρ), linear shrinkage, X-ray Diffraction (XRD), Fourier Transforms Infrared (FTIR) and Field Emission Scanning Electron Microscopy (FESEM). High content of Ca and Si in CS and SLS glass respectively promote the use of waste materials in production of ASF composition. The density and linear shrinkage of the samples varies with sintering temperature. Besides, XRD results showed that fluorapatite (Ca5(PO4)3F) is a main phase existed in all samples meanwhile FTIR confirmed the presence of silica and also the formation of Ca P phase in the composition. FESEM analysis showed the increasing of grain size and formation of needle-like microstructure known as fluorapatite when sintering temperature increase. Overall results promoted the ASF glass ceramics samples produced from waste materials as a high potential candidate for dental application.

Change in the surface OH group on soda lime silicate glass and silica glass after heat treatment in nitrogen atmosphere