scholarly journals Dynamic fracture of inorganic glasses by hard spherical and conical projectiles

2015 ◽  
Vol 373 (2038) ◽  
pp. 20140135 ◽  
Author(s):  
M. Munawar Chaudhri
Keyword(s):  
Crack Growth ◽  
High Speed ◽  
Soda Lime ◽  
Fused Silica ◽  
Soda Lime Glass ◽  
Dynamic Crack ◽  
Inorganic Glasses ◽  
The Impact ◽  
Hertzian Cone ◽  
Crack Bifurcation

In this article, high-speed photographic investigations of the dynamic crack initiation and propagation in several inorganic glasses by the impact of small spherical and conical projectiles are described. These were carried out at speeds of up to approximately 2×10 6 frames s −1 . The glasses were fused silica, ‘Pyrex’ (a borosilicate glass), soda lime and B 2 O 3 . The projectiles were 0.8–2 mm diameter spheres of steel, glass, sapphire and tungsten carbide, and their velocities were up to 340 m s −1 . In fused silica and Pyrex, spherical projectiles' impact produced Hertzian cone cracks travelling at terminal crack velocities, whereas in soda-lime glass fast splinter cracks were generated. No crack bifurcation was observed, which has been explained by the nature of the stress intensity factor of the particle-impact-generated cracks, which leads to a stable crack growth. Crack bifurcation was, however, observed in thermally tempered glass; this bifurcation has been explained by the tensile residual stress and the associated unstable crack growth. A new explanation has been proposed for the decrease of the included angle of the Hertzian cone cracks with increasing impact velocity. B 2 O 3 glass showed dynamic compaction and plasticity owing to impact with steel spheres. Other observations, such as total contact time, crack lengths and response to oblique impacts, have also been explained.

High Speed Liquid Impact Onto Wetted Solid Surfaces

1994 ◽  
Vol 116 (2) ◽  
pp. 345-348 ◽  
Author(s):  
H. H. Shi ◽  
J. E. Field ◽  
C. S. J. Pickles
Keyword(s):  
Shock Wave ◽  
Liquid Layer ◽  
Solid Surface ◽  
High Speed ◽  
Shear Failure ◽  
Soda Lime ◽  
Liquid Jet ◽  
Soda Lime Glass ◽  
The Impact

The mechanics of impact by a high-speed liquid jet onto a solid surface covered by a liquid layer is described. After the liquid jet contacts the liquid layer, a shock wave is generated, which moves toward the solid surface. The shock wave is followed by the liquid jet penetrating through the layer. The influence of the liquid layer on the side jetting and stress waves is studied. Damage sites on soda-lime glass, PMMA (polymethylmethacrylate) and aluminium show the role of shear failure and cracking and provide evidence for analyzing the impact pressure on the wetted solids and the spatial pressure distribution. The liquid layer reduces the high edge impact pressures, which occur on dry targets. On wetted targets, the pressure is distributed more uniformly. Despite the cushioning effect of liquid layers, in some cases, a liquid can enhance material damage during impact due to penetration and stressing of surface cracks.

Scanning tunneling microscope observations of the mirror region of silicate glass fracture surfaces

1994 ◽  
Vol 9 (2) ◽  
pp. 476-485 ◽  
Author(s):  
D.M. Kulawansa ◽  
L.C. Jensen ◽  
S.C. Langford ◽  
J.T. Dickinson ◽  
Yoshihisa Watanabe
Keyword(s):  
Scanning Tunneling Microscope ◽  
Soda Lime ◽  
Local Deformation ◽  
Fused Silica ◽  
Scanning Tunneling ◽  
Soda Lime Glass ◽  
Self Similarity ◽  
Tunneling Microscope ◽  
Fracture Surfaces ◽  
Mirror Region

We report scanning tunneling microscope images of gold-coated fracture surfaces of soda lime glass and fused silica in the mirror region. The scans show a variety of nanometer scale features that are attributed to fracture phenomena at this scale. We find considerable similarity to the structures observed in regions of extensive crack branching (e.g., “mist”). The density of these features increases as one progresses away from the crack origin toward the mirror-mist boundary. Comparisons are made between soda lime glass and fused silica, revealing differences in the local deformation behavior of these two materials. Self-similarity of the observed structures is probed by measurements of the fractal dimension, Df, of the surfaces created in soda lime glass near the mirror-mist boundary, where we observe 2.17 > Df > 2.40.

scholarly journals 2.1.3 Composition of Impact-Plasma measured by a HELIOS-Micrometeoroid-Detector

1976 ◽  
Vol 31 ◽  
pp. 164-164
Author(s):  
B.-K. Dalmann ◽  
E. Grün ◽  
J. Kissel
Keyword(s):  
High Sensitivity ◽  
Soda Lime ◽  
Dust Particles ◽  
Soda Lime Glass ◽  
High Noise ◽  
M 10 ◽  
Nasa Ames Research ◽  
Characteristic Features ◽  
The Masses ◽  
The Impact

The composition of the impact-plasma, produced by dust particles hitting an Au-target was measured, using a model of the HELIOS-mlcrometeoroid-detector. The 2 MV dust accelerators of the MPI für Kernphysik, Heidelberg, and the NASA Ames Research Center were used to accelerate particles consisting of Al, Al2O3, SiO2, Soda-Lime-Glass, Polystyrene and Kaolin to velocities between 2 km/sec and 15 km/sec. Fe-projectiles could be accelerated up to 40 km/sec. The masses of the dust grains were between 10−15 g and 3 × 10−10 g. The experiments showed, that because of the characteristic features of the measured spectra it is possible to separate noise events from impacts even at a high noise background. The smallest particles (m 10−15 g) triggering the experiment produce spectra well above the noise level (more than a factor 10) because of the high sensitivity of the ion-detector (multiplier).

scholarly journals Machinability of Soda Lime Glass in High Speed End Milling

2018 ◽  
Vol 290 ◽  
pp. 012036
Author(s):  
Mohamed Konneh ◽  
Mst. Nasima Bagum ◽  
Tasnim Firdaus Bt. Mohamed Arif ◽  
Mohammad Yeakub Ali
Keyword(s):  
High Speed ◽  
End Milling ◽  
Soda Lime ◽  
Soda Lime Glass

scholarly journals Rate-Dependent Cohesive Zone Model for Fracture Simulation of Soda-Lime Glass Plate

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 749 ◽  
Author(s):  
Dong Li ◽  
Demin Wei
Keyword(s):  
Strain Rate ◽  
Cohesive Zone ◽  
Cohesive Zone Model ◽  
Glass Plate ◽  
Soda Lime ◽  
Soda Lime Glass ◽  
Zone Model ◽  
Rate Dependent ◽  
Fracture Simulation ◽  
The Impact

In this paper, rate-dependent cohesive zone model was established to numerical simulate the fracture process of soda-lime glass under impact loading. Soda-lime glass is widely used in architecture and automobile industry due to its transparency. To improve the accuracy of fracture simulation of soda-lime glass under impact loading, strain rate effect was taken into consideration and a rate-dependent cohesive zone model was established. Tensile-shear mixed mode fracture was also taken account. The rate-dependent cohesive zone model was implemented in the commercial finite element code ABAQUS/Explicit with the user subroutine VUMAT. The fracture behavior of a monolithic glass plate impacted by a hemispherical impactor was simulated. The simulation results demonstrated that the rate-dependent cohesive zone model is more suitable to describe the impact failure characteristics of a monolithic glass plate, compared to cohesive zone model without consideration of strain rate. Moreover, the effect of the strain rate sensitivity coefficient C, the mesh size of glass plate and the impact velocity on the fracture characteristics were studied.

EXPERIMENTAL STUDY OF THE IMPACT DAMAGE ON AN Al2O3-COATED GLASS UNDER STRESS

2006 ◽  
Vol 20 (25n27) ◽  
pp. 4529-4534 ◽  
Author(s):  
CHANG-MIN SUH ◽  
SUNG-HO KIM ◽  
DUCK-YOUNG SUH
Keyword(s):  
Compressive Stress ◽  
Impact Test ◽  
Impact Damage ◽  
Soda Lime ◽  
Target Distance ◽  
Soda Lime Glass ◽  
Optimum Conditions ◽  
Stereo Microscope ◽  
Steel Balls ◽  
The Impact

The impact damage of an Al 2 O 3-coated soda-lime glass under tensile and compressive stress conditions was investigated by an impact test using a steel ball (2mm dia.). The size of the glass specimens was 40×40×5( mm ). In order to change the porosity percent of each specimen, the target distance was set at 120mm and 70mm. Also, the effect of the thickness of the coating layer was shown by two amounts (100 μm and 50 μm). The velocity of the steel balls was set between 30 and 60m/s. After the impact test, the crack patterns and lengths were measured using a stereo-microscope. The tensile and compressive specimens were prepared by inflation and deflation of air pressure within a pressure vessel. It was confirmed that the crack length of the glass under tensile stress was longer than that of glass under compressive stress. Also, the optimum conditions were a target distance of 70mm and 100 μm of a coating thickness, thus resulting in a minimization of porosity percent and area.

Slump Molding of Microchannel Arrays in Soda-Lime Glass for Bioanalytical Device Development

2014 ◽  
Vol 2 (4) ◽  
Author(s):  
Richard E. Billo ◽  
Paul A. Wilson ◽  
John W. Priest ◽  
Mario Romero-Ortega ◽  
Shannon R. Brunskill ◽  
...  
Keyword(s):  
Glass Substrate ◽  
High Speed ◽  
Chemical Reactivity ◽  
Soda Lime ◽  
Nerve Tissue ◽  
Mold Material ◽  
Soda Lime Glass ◽  
Molding Process ◽  
Soda Lime Glass Substrate ◽  
Lab On Chip

A slump molding process was developed to place microchannel geometries in a soda-lime glass substrate for a lab-on-chip bioanalytical device. The process was developed to overcome the biological and chemical reactivity associated with current polymer lab-on-a-chip substrates, and as an alternative to using more expensive glass material. A high speed micro mill and UV laser micromachining center were used to fabricate the negative geometries in the graphite mold material that was used. The slumping process of the soda-lime glass was done using a glass kiln. Microchannel dimensions were in the mesa scale range of 50 μm width × 10 μm depth. The heating schedule for slump molding of the soda-lime glass to take its final shape to these dimensions was determined and documented. The functionality of the slumping process and resultant soda-lime glass device was validated through murine nerve tissue experiments conducted through the bioanalytical device that was developed. The research represented a novel use of slump molding, a process traditionally known for producing artistic works for: (a) embossing engineered microchannels and (b) reliably processing a soda-lime glass substrate, a material known to be difficult to work with due to its poor physical properties.

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