Study of Bismuth Telluride Crystal Strength

2019 ◽  
pp. 1-8
Author(s):  
A. A. Gorbatovskiy
Keyword(s):  
Tensile Strength ◽  
Bismuth Telluride ◽  
Elasticity Modulus ◽  
Testing Machine ◽  
Bend Testing ◽  
Instron Testing Machine ◽  
Measurement Results ◽  
Strength Tests ◽  
Semiconductor Properties

The article presents results of strength tests of bismuth telluride prismatic samples obtained by growing crystals. These crystals have semiconductor properties and are used in the heat machines, the run-ability of which largely depends on the strength of crystals. Data available in the literature are significantly different from each other. It has been shown that, the most consistent strength tests results are obtained in case of bend testing. The measurement results of the elasticity modulus and tensile strength are given. For tests, an INSTRON testing machine with maximum direct stress of the 1000 H was used.

scholarly journals Bonding of plywood 

2016 ◽  
Vol 62 (No. 4) ◽  
pp. 198-204
Author(s):  
M. Brožek
Keyword(s):  
Tensile Strength ◽  
Testing Machine ◽  
Strength Testing ◽  
Bonded Joints ◽  
Rupture Force ◽  
Oblique Direction ◽  
Direction Angle ◽  
Economical Evaluation ◽  
Wood Bonding ◽  
Strength Tests

The contribution contains results of bonded joints strength tests. The tests were carried out according to the modified standard ČSN EN 1465 (66 8510):2009. The spruce three-ply wood of 4 mm thickness was used for bonding according to ČSN EN 636 (49 2419):2013. The test samples of 100 × 25 mm size were cut out from a semi-product of 2,440 × 1,220 mm size in the direction of its longer side (angle 0°), in the oblique direction (angle 45°) and in the direction of its shorter side (crosswise – angle 90°). The bonding was carried out using eight different domestic as well as foreign adhesives according to the technology prescribed by the producer. All used adhesives were designated for wood bonding. At the bonding the consumption of the adhesive was determined. After curing, the bonded assemblies were loaded using a universal tensile-strength testing machine up to the rupture. The rupture force and the rupture type were registered. Finally, the technical-economical evaluation of the experiments was carried out. 

Design of a snap connector to connect panel elements

2019 ◽  
Vol 108 ◽  
pp. 26-38
Author(s):  
ŁUKASZ MATWIEJ ◽  
ROBERT KŁOS ◽  
MIROSŁAW BONOWSKI
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Testing Machine ◽  
Numerical Calculations ◽  
Strength Testing ◽  
Mechanical Properties Of Materials ◽  
Strength Tests ◽  
Design Requirements ◽  
Properties Of Materials

Design of a snap connector to connect panel elements. The aim of this study was to design, manufacture and verify the tensile strength of a prototype snap connector to be used to connect panel elements. Firstly, analyses were conducted on solutions of commercially available designs for connectors invisible from the cabinet’s outside and those with minimized visibility. While searching for the best concept of connector design, three proposals were prepared, of which – after thorough analysis of design – one concept was selected. In the next step, the adopted solution was improved so that the connector met the previously formulated design requirements. In the course of further analyses, the causes and effects of failure were verified in order to limit or eliminate potential defects. In the next stage of the study, numerical calculations were conducted for the nut and the connector, concerning tensile strength, using the Autodesk Simulation Multiphysics program. After a prototype connector was manufactured, tensile strength tests were conducted on the connector using a strength testing machine. Experiments verified the correctness of the developed design in terms of geometry and the physico-mechanical properties of materials of individual elements, and resulted in possible changes proposed in the design of the final connector product.

scholarly journals Assessing the effect of Alnus roots on hillslope stability in order to use in soil bioengineering

2013 ◽  
Vol 59 (No. 11) ◽  
pp. 417-423 ◽  
Author(s):  
R. Naghdi ◽  
S. Maleki ◽  
E. Abdi ◽  
R. Mousavi ◽  
M. Nikooy
Keyword(s):  
Tensile Strength ◽  
Factor Of Safety ◽  
Testing Machine ◽  
Soil Strength ◽  
Strength Parameters ◽  
Root Characteristics ◽  
Root Area ◽  
Instron Testing Machine ◽  
Hillslope Stability ◽  
Alnus Subcordata

The role of plant roots in stabilizing slopes is obvious, but the amount of the effect is varied in different species. The purpose of this study was to evaluate the effect of alder (Alnus subcordata) roots on hillslope stability. The profile trenching method was used to obtain root characteristics and a standard Instron testing machine was used for determining the tensile strength of roots. Direct shear test with undisturbed samples was used for determining the soil strength parameters. Using the results of biotechnical characteristics and the Wu model, the reinforcement effect was calculated. Using the reinforcement values and soil strength parameters and Slip4Ex program, factor of safety with and without vegetation was calculated. The obtained results indicated that the root density and number of roots decreased with increasing depth and the average root area ratio was 0.071% ± 0.01. Tensile strength decreased with increasing diameter of roots following the power function with an average of 16.29 ± 3.10 MPa. The minimum and maximum of reinforcement were 0.55 KPa and 110.76 KPa, respectively. The results of this paper augment the knowledge about biotechnical characteristics of root systems of Alder species and indicate that this species increases the factor of safety about 16.79%.

scholarly journals Performance of Additive Blended High Volume Fly Ash Concrete - A Systematic Literature Study

2021 ◽  
Keyword(s):  
Tensile Strength ◽  
Fly Ash ◽  
Elasticity Modulus ◽  
Flexural Rigidity ◽  
Concrete Specimen ◽  
High Volume ◽  
Literature Study ◽  
Fly Ash Concrete ◽  
High Volume Fly Ash ◽  
Strength Tests

Abstract. Replacing cement with fly ash has recently created huge popularity among the construction field because of its huge production, efficient resources and sustainability aspect. This study is made to determine the High-Volume fly-ash concrete (HVFC) performance by adding additives. The general used concrete mixture is prepared by proportioning fly ash (40-50%) as a replacement. The concrete specimen was found to have better compressive strengths and hence, passed the strength tests. By incorporating additive Nano-SiO2 and superplasticizer the following compression, flexural rigidity, splitting tensile strength and elasticity modulus were observed in the specimen to establish the cement and fly ash bond. The concrete performance mix with replacement fly ash at different percent was found to have good compressive strength during test and stayed undamaged during the entire period of exposure.

scholarly journals Mechanical properties of polyester composite reinforced fibers hybrid bamboo - Musa acuminata stem fiber as raw material of rear bumper vehicle

2021 ◽  
Vol 8 (3) ◽  
pp. 001-007
Author(s):  
Sujita Darmo Darmo ◽  
Rudy Sutanto Sutanto
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elasticity Modulus ◽  
Low Cost ◽  
Testing Machine ◽  
Musa Acuminata ◽  
Bamboo Fiber ◽  
Raw Material ◽  
Polyester Composite ◽  
Polyester Composites

In the present study fiber hybrid (bamboo fiber and Musa acuminata stem fibers (MASF) were reinforced polyester composite, for enhancing mechanical properties. The natural fibers composite has gained its importance due to its low cost, substitute for artificial fiber, low price, able to reduce sound, environmentally friendly, has a low density, good fit and ability to absorb impact energy. It’s possible to use it as a vehicle accessory such as a rear bumper vehicle. This study aims to investigate the tensile stress-strain, elasticity modulus and the microstructure of fracture of polyester fiberglass composite reinforced bamboo fiber and MASF hybrid. Polyester matrix type 157 is used BQTN and G3253T, MEKPO catalyst. The mechanical properties test was carried out by universal testing machine (UTM) test instrument, observing the microstructure of the occurrence of fracture by using scanning electron microscope (SEM). The test specimens produced the vacuum infusion method. The results of this study indicate that the addition of more MASF and the outer layer content can increase the tensile strength, elasticity modulus of polyester composites reinforced MASF with woven, random arrangement is better than that of polyester composites reinforced bamboo fiber. So that in the manufacture of polyester composites reinforced hybrid fiber the use of more MASF than bamboo fiber can provide better tensile strength and elasticity modulus. The configuration with the outer MASF layer can also increase the value of tensile strength, elasticity modulus on the specimen compared to the configuration with bamboo fiber outside. The microstructure of fracture for fiber for each configuration of MASF content there are long fibers and also in bamboo fibers there are fibers that are pulled out. The diameter of the bamboo fiber reinforcement is larger so that the load transfer is not as effective as MASF.

scholarly journals Influence of Temporary Cements on the Bond Strength of Self-Adhesive Cement to the Metal Coronal Substrate

2015 ◽  
Vol 26 (6) ◽  
pp. 637-641
Author(s):  
Raniel Fernandes Peixoto ◽  
Caio Rocha de Aguiar ◽  
Eduardo Santana Jacob ◽  
Ana Paula Macedo ◽  
Maria da Gloria Chiarello de Mattos ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Bond Strength ◽  
Testing Machine ◽  
Resin Cement ◽  
Adhesive Resin ◽  
Cast Metal ◽  
Air Jet ◽  
Significant Difference ◽  
Strength Tests ◽  
Adhesive Resin Cement

This research evaluated the influence of temporary cements (eugenol-containing [EC] or eugenol-free [EF]) on the tensile strength of Ni-Cr copings fixed with self-adhesive resin cement to the metal coronal substrate. Thirty-six temporary crowns were divided into 4 groups (n=9) according to the temporary cements: Provy, Dentsply (eugenol-containing), Temp Cem, Vigodent (eugenol-containing), RelyX Temp NE, 3M ESPE (eugenol-free) and Temp Bond NE, Kerr Corp (eugenol-free). After 24 h of temporary cementation, tensile strength tests were performed in a universal testing machine at a crosshead speed of 0.5 mm/min and 1 kN (100 kgf) load cell. Afterwards, the cast metal cores were cleaned by scraping with curettes and air jet. Thirty-six Ni-Cr copings were cemented to the cast metal cores with self-adhesive resin cement (RelyX U200, 3M ESPE). Tensile strength tests were performed again. In the temporary cementation, Temp Bond NE (12.91±2.54) and Temp Cem (12.22±2.96) presented the highest values of tensile strength and were statistically similar to each other (p>0.05). Statistically significant difference (p<0.05) was observed only between Provy (164.44±31.23) and Temp Bond NE (88.48±21.83) after cementation of Ni-Cr copings with self-adhesive resin cement. In addition, Temp Cem (120.68±48.27) and RelyX Temp NE (103.04±26.09) showed intermediate tensile strength values. In conclusion, the Provy eugenol-containing temporary cement was associated with the highest bond strength among the resin cements when Ni-Cr copings were cemented to cast metal cores. However, the eugenol cannot be considered a determining factor in increased bond strength, since the other tested cements (1 eugenol-containing and 2 eugenol-free) were similar.

Calculations used for assessment of rapid maxillary expansion

ORL ro ◽  
2016 ◽  
Vol 1 (1) ◽  
pp. 24-26
Author(s):  
Ruxandra Bartok ◽  
Bogdan Dimitriu Dimitriu ◽  
Constantin Vârlan ◽  
Radu Stanciu ◽  
Georgiana Moldoveanu ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Elasticity Modulus ◽  
Rapid Maxillary Expansion ◽  
Laboratory Animals ◽  
Maxillary Expansion ◽  
Literature Reference ◽  
Bone Changes ◽  
Upper Jaw ◽  
Materials Used

Rapid maxillary expansion is defined as the release of medio-palatine suture using an orthopedic forces. The role of this procedure is to expand  the upper jaw in order to achieve the  broadening of the upper arch. This study was initiated to quantify the effects of disjunction and post- treatment bone changes, after an adequate contention which lasted for three weeks. This study  is  carried on laboratory animals (common breed rabbit) to determine tensile strength and the elasticity modulus of  biological materials  used in orthdodontics. The results of the study are consistent with those reported in the literature reference.  

Mechanical Behaviour of CoCrMo Alloy with Si Content

2015 ◽  
Vol 754-755 ◽  
pp. 1017-1022 ◽  
Author(s):  
Petrică Vizureanu ◽  
Mirabela Georgiana Minciună ◽  
Dragoş Cristian Achiţei ◽  
Andrei Victor Sandu ◽  
Kamarudin Hussin
Keyword(s):  
Tensile Strength ◽  
Chemical Composition ◽  
Testing Machine ◽  
Base Material ◽  
Optical Emission ◽  
Experimental Tests ◽  
Optical Emission Spectrometry ◽  
Emission Spectrometry ◽  
Standard Samples

.The paper present aspects about the obtaining of non-precious dental alloys (type CoCrMo and CoCrMoSi7), the determination of chemical composition by optical emission spectrometry and the experimental tests for determining the tensile strength, made on standard plate samples. The base material used in experiments was a commercial alloy, from CoCrMo system, which belongs to the class of dental non-precious alloys, intended to medical applications. The obtaining of studied alloy was made on arc re-melting installation, under vacuum, type MRF ABJ 900. The process followed to realize a rapid melting, with a maximum admissible current intensity. The samples for tests were obtained by casting in an electric arc furnace, under vacuum, in optimal conditions for melting and solidification and processing by electro-erosion, to eliminate all the disturbing factors which come by processing conditions for the samples. The determination of chemical composition for cobalt based alloys, by optical emission spectrometry, was made on SpectromaxX equipment with spark. The electrical discharge is made with the elimination of an energy quantity, fact which determine plasma forming and light issue. Tensile tests for standard samples, made from cobalt based alloy, was made on Instron 3382 testing machine, and assisted by computer. The obtained results are: elongation, elasticity modulus, tensile strength and offer complete information about the analyzed mechanical properties. For the certitude of obtained experimental results, the tests were made on samples with specific dimensions according ISO 6892-1:2009(E) standard, both for the tensile strength, and also machine operation.

Using Embossing to Create a Fiber Reinforced Honeycomb Composite

2005 ◽  
Vol 127 (2) ◽  
pp. 257-262 ◽  
Author(s):  
William Jordan
Keyword(s):  
Tensile Strength ◽  
Composite Material ◽  
Carbon Fibers ◽  
Flexural Modulus ◽  
Testing Machine ◽  
Charpy Impact ◽  
Tensile Tests ◽  
Hydraulic Testing ◽  
Charpy Impact Toughness ◽  
Bend Tests

This research project used hot embossing to create a strong and tough polymeric based composite structure. A honeycomb type structure was created by pressing small grooves into thin polycarbonate sheets. A trapezoidal die was used to create hexagonal shaped channels in the polymeric sheet. A number of these sheets were then bonded together to form a composite material. Carbon fibers were embedded into the channels in some of the laminates. The embossing process was carried out at an elevated temperature in an environmental chamber attached to an MTS servo hydraulic testing machine. The grooved structure had a 31% to 45% decrease in the apparent density compared to the ungrooved specimens. Bend tests, tensile tests, and Charpy impact tests were performed on laminates made from this material. The specific values of tensile strength, flexural modulus, and Charpy impact toughness were increased. A small percentage of fibers significantly increased both the stiffness and strength of the laminate.

scholarly journals The effect of liquid nitrogen cooling on coal cracking and mechanical properties

2018 ◽  
Vol 36 (6) ◽  
pp. 1609-1628 ◽  
Author(s):  
Chengzheng Cai ◽  
Feng Gao ◽  
Yugui Yang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Acoustic Emission ◽  
Liquid Nitrogen ◽  
Wave Velocity ◽  
Count Rate ◽  
Initial State ◽  
Nitrogen Injection ◽  
Strength Tests ◽  
Liquid Nitrogen Cooling

Liquid nitrogen is a type of super-cryogenic fluid, which can cause the reservoir temperature to decrease significantly and thereby induce formation rock damage and cracking when it is injected into the wellbore as fracturing fluid. An experimental set-up was designed to monitor the acoustic emission signals of coal during its contact with cryogenic liquid nitrogen. Ultrasonic and tensile strength tests were then performed to investigate the effect of liquid nitrogen cooling on coal cracking and the changes in mechanical properties thereof. The results showed that acoustic emission phenomena occurred immediately as the coal sample came into contact with liquid nitrogen. This indicated that evident damage and cracking were induced by liquid nitrogen cooling. During liquid nitrogen injection, the ring-down count rate was high, and the cumulative ring-down counts also increased rapidly. Both the ring-down count rate and the cumulative ring-down counts during liquid nitrogen injection were much greater than those in the post-injection period. Liquid nitrogen cooling caused the micro-fissures inside the coal to expand, leading to a decrease in wave velocity and the deterioration in mechanical strength. The wave velocity, which was measured as soon as the sample was removed from the liquid nitrogen (i.e. the wave velocity was recorded in the cooling state), decreased by 14.46% on average. As the cryogenic samples recovered to room temperature, this value increased to 18.69%. In tensile strength tests, the tensile strengths of samples in cooling and cool-treated states were (on average) 17.39 and 31.43% less than those in initial state. These indicated that both during the cooling and heating processes, damage and cracking were generated within these coal samples, resulting in the acoustic emission phenomenon as well as the decrease in wave velocity and tensile strength.

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