Influence of Shear and Micro-Shear Tests on Adhesive Resistance and Fracture Types of Direct Restorative Systems in Dentin

2019 ◽  
Vol 958 ◽  
pp. 99-103
Author(s):  
E.C. Carvalho ◽  
Jayme Pereira de Gouvêa ◽  
T.C.F. Melo-Silva ◽  
C.L. Melo-Silva ◽  
Ágatha Borges Teixeira ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Adhesive Strength ◽  
Composite Resin ◽  
Mechanical Tests ◽  
Shear Tests ◽  
Universal System ◽  
Dentin Surface ◽  
Human Dentin ◽  
Fracture Types ◽  
Type Of Failure

The aim of this study was to evaluate the influence of shear and micro-shear tests on adhesive resistance and on defects in restorations in human dentin. The teeth were sectioned and embedded. The dentin surface was treated with universal system adhesive and the samples were divided into two groups. In the first, composite resin pins were fixed with 1 mm diameter and in the second, pins with 2 mm. After mechanical tests the samples were taken to the SEM for analysis of fractures. Tensile strength on G1 was 16 MPa and on G2 20 MPa. The fractures occurred after shear were mostly mixed and cohesive in dentin. On micro-shear adhesive and mixed, no cohesive. It can deduce that, the diameter of the pin influenced the adhesive resistance and the type of failure. Therefore, for evaluation of adhesive strength in dentin the test indicated is micro-shear.

Effect of silver nitrate on some mechanical properties of heat polymerizing acrylic resins

2019 ◽  
Vol 14 (1) ◽  
pp. 110
Author(s):  
Assiss. Prof. Dr. Sabiha Mahdi Mahdi ◽  
Dr. Firas Abd K. Abd K.
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Silver Nitrate ◽  
Surface Hardness ◽  
Mechanical Tests ◽  
Hardness Tester ◽  
Acrylic Resins ◽  
The Difference

Aim: The aimed study was to evaluate the influence of silver nitrate on surfacehardness and tensile strength of acrylic resins.Materials and methods: A total of 60 specimens were made from heat polymerizingresins. Two mechanical tests were utilized (surface hardness and tensile strength)and 4 experimental groups according to the concentration of silver nitrate used.The specimens without the use of silver nitrate were considered as control. Fortensile strength, all specimens were subjected to force till fracture. For surfacehardness, the specimens were tested via a durometer hardness tester. Allspecimens data were analyzed via ANOVA and Tukey tests.Results: The addition of silver nitrate to acrylic resins reduced significantly thetensile strength. Statistically, highly significant differences were found among allgroups (P≤0.001). Also, the difference between control and experimental groupswas highly significant (P≤0.001). For surface hardness, the silver nitrate improvedthe surface hardness of acrylics. Highly significant differences were statisticallyobserved between control and 900 ppm group (P≤0.001); and among all groups(P≤0.001)with exception that no significant differences between control and150ppm; and between 150ppm and 900ppm groups(P>0.05).Conclusion: The addition of silver nitrate to acrylics reduced significantly the tensilestrength and improved slightly the surface hardness.

Effect of fillers on mechanical properties of recycled low density polyethylene composites under weathered condition

2020 ◽  
Vol 15 (3) ◽  
pp. 44-49
Author(s):  
Ibiyemi A. Idowu ◽  
Olutosin O. Ilori
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Pure Water ◽  
Mechanical Tests ◽  
Filler Loading ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Hardness Property ◽  
Recycled Low Density Polyethylene ◽  
Polyethylene Composites

The study examined the effect of fillers on the mechanical properties of the recycled low density polyethylene composites under weathered condition with a view of managing the generation and disposal of plastic wastes. Discarded pure water sachets and fillers (glass and talc) were sourced and recycled. Recycled low density polyethylene (RLDPE) and preparation of RLDPE/glass, RLDPE/talc and RLDPE/glass/talc composites were carried out using a furnace at compositions of 0 – 40% in steps of 10% by weight. The mixtures were poured into hand-laid mould. The samples produced were exposed to sunlight for eight (8) weeks and their mechanical properties were studied. The results of mechanical tests revealed that tensile strength decreased with increasing filler loading while impact strength and hardness property increased marginally and considerably with increasing filler loading for all the composites respectively. The study concluded that glass and talc were able to reinforce recycled low density polyethylene under weathered condition. Keywords: Recycled Low Density Polyethylene (RLDPE); Fillers; Glass, Talc; Weathering condition; Sunlight; and Mechanical properties; Tensile strength, Impact and hardness

An Experimental Investigation on Mechanical and Wear Properties of Al7075/SiCp Composites: Effect of SiC Content and Particle Size

2017 ◽  
Vol 140 (3) ◽  
Author(s):  
Thella Babu Rao
Keyword(s):  
Particle Size ◽  
Tensile Strength ◽  
Wear Resistance ◽  
Ultimate Tensile Strength ◽  
Matrix Material ◽  
Mechanical Tests ◽  
Experimental Investigations ◽  
Wear Properties ◽  
Sic Particles ◽  
Sic Particle

One of the major advantages of metal matrix composites (MMCs) is that their tailorable properties meet the specific requirements of a particular application. This paper deals with the experimental investigations done on the effects of the reinforcement particulate size and content on the Al7075/SiC composite. The composites were manufactured using stir casting technique. The effect of SiC particle size (25, 50, and 75 μm) and particulate content (5, 10, and 15 wt %) on the microstructural, mechanical properties, and wear rate of the composites was studied and the results were analyzed for varied conditions of reinforcement. Scanning electron microscope (SEM) examinations were used to assess the dispersion of SiC particles reinforced into the matrix alloy and was found with reasonably uniform with minimal particle agglomerations and with good interfacial bonding between the particles and matrix material. X-ray diffraction (XRD) analysis confirmed the presence of Al and SiC with the composite. The results of mechanical tests showed that the increasing SiC particle size and content considerably enhanced the ultimate tensile strength and hardness of the composites while the ductility at this condition was decreased. The highest ultimate tensile strength of 310 MPa and hardness of 126 BHN were observed for the composites containing 15 wt %. SiC at 75 μm. Lesser the wear resistance of the reference alloy while it was enhanced up to 40% with the composites. The wear resistance was increased up to 1200 m of sliding distance for all the composites, whereas for the composite containing 75 μm SiC particles, it was extended up to 1800 m.

scholarly journals The Influence of Sample Preparation on the Strength Results ofa Pan-based Carbon Fiber

2010 ◽  
Vol 4 (4) ◽  
pp. 329-337
Author(s):  
Fabio Pereira ◽  
◽  
Fabiana Vieira ◽  
Luiz de Castro ◽  
Ricardo Michel ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Carbon Fiber ◽  
Sample Preparation ◽  
Young’S Modulus ◽  
Carbon Fibers ◽  
Weibull Modulus ◽  
Strong Influence ◽  
Mechanical Tests ◽  
Preparation Process

In this work the influence of different configurations in the sample preparation process on commercial polyacrylonitrile-based carbon fibers mechanical tests were studied. Mechanical properties, such as tensile strength, Young’s modulus, elongation and Weibull modulus, were evaluated. The results showed that all sample preparation steps may have strong influence on the results.

scholarly journals Tension mechanical properties of recycled glass-epoxy composite material

2012 ◽  
pp. 189-198 ◽  
Author(s):  
Jelena Petrovic ◽  
Darko Ljubic ◽  
Marina Stamenovic ◽  
Ivana Dimic ◽  
Slavisa Putic
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Composite Material ◽  
Composite Materials ◽  
Modulus Of Elasticity ◽  
Epoxy Composite ◽  
Raw Materials ◽  
Mechanical Tests ◽  
Recycled Glass ◽  
Before And After

The significance of composite materials and their applications are mainly due to their good properties. This imposes the need for their recycling, thus extending their lifetime. Once used composite material will be disposed as a waste at the end of it service life. After recycling, this kind of waste can be used as raw materials for the production of same material, which raises their applicability. This indicates a great importance of recycling as a method of the renowal of composite materials. This study represents a contribution to the field of mechanical properties of the recycled composite materials. The tension mechanical properties (tensile strength and modulus of elasticity) of once used and disposed glass-epoxy composite material were compared before and after the recycling. The obtained results from mechanical tests confirmed that the applied recycling method was suitable for glass-epoxy composite materials. In respect to the tensile strength and modulus of elasticity it can be further assessed the possibility of use of recycled glass-epoxy composite materials.

scholarly journals An Experimental Study on a Composite Bonding Structure for Steel Bridge Deck Pavements

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Xiaoguang Zheng ◽  
Qi Ren ◽  
Huan Xiong ◽  
Xiaoming Song
Keyword(s):  
Tensile Strength ◽  
Shear Strength ◽  
Epoxy Resin ◽  
Bonding Strength ◽  
Bridge Deck ◽  
Steel Bridge ◽  
Shear Tests ◽  
Bonding Structure ◽  
Asphalt Overlay ◽  
Strength Tests

As one of the major contributors to the early failures of steel bridge deck pavements, the bonding between steel and asphalt overlay has long been a troublesome issue. In this paper, a novel composite bonding structure was introduced consisting of epoxy resin micaceous iron oxide (EMIO) primer, solvent-free epoxy resin waterproof layer, and ethylene-vinyl acetate (EVA) hot melt pellets. A series of strength tests were performed to study its mechanical properties, including pull-off strength tests, dumbbell tensile tests, lap shear tests, direct tension tests, and 45°-inclined shear tests. The results suggested that the bonding structure exhibited fair bonding strength, tensile strength, and shear strength. Anisotropic behaviour was also observed at high temperatures. For epoxy resin waterproof layer, the loss of bonding strength, tensile strength, and shear strength at 60°C was 70%, 35%, and 39%, respectively. Subsequent pavement performance-oriented tests included five-point bending tests and accelerated wheel tracking tests. The impacts of bonding on fatigue resistance and rutting propagation were studied. It was found that the proposed bonding structure could provide a durable and well-bonded interface and was thus beneficial to prolong the fatigue lives of asphalt overlay. The choice of bonding materials was found irrelevant to the ultimate rutting depth of pavements. But the bonding combination of epoxy resin waterproof and EVA pellets could delay the early-stage rutting propagation.

scholarly journals Comparison Adhesive strength of Resin Composite between Total-etch and Self-etch Techniques on Enamel After Fluoride Application

2021 ◽  
Vol 11 (1) ◽  
pp. 38
Author(s):  
Widya Saraswati ◽  
Adioro Soetojo ◽  
Yasmin Tasya Brilyanti
Keyword(s):  
Adhesive Strength ◽  
Composite Resin ◽  
Resin Composite ◽  
Adhesive System ◽  
Review Literature ◽  
The Self ◽  
White Spot Lesion ◽  
Fluoride Treatment ◽  
Topical Fluoride ◽  
Self Etch

Background : White Spot Lesion (WSL) is caused by Streptococcus Mutan which causes demineralization of teeth. One of the treatments of WSL is topical application of fluoride which aims to remineralize the teeth. However, if topical fluoride treatment does not give satisfactory results, alternative treatments can be made using restorative treatments, one of which is veneers. The procedure for applying veneers requires the application of an adhesive system. The adhesive system used to apply veneers is self-etch and total-etch. Several references state that the application of fluoride which aims to remineralize teeth can influence the adhesiv strength of the restorative material using self etch and total-etch techniques. Purpose : To determine the effect of composite resin adhesion strength between total-etch and self etch techniques on enamel after fluoride application. Review : Literature sources used in the preparation of the article through several databases with descriptions of the effects of fluoride application before total-etch and/or self etch administration. From the existing references, it was found that the application of fluoride before the total-etch system had a less significant effect on the adhesiv strength. Whereas in the self etch system, fluoride application has a significant effect on the adhesiv strength. Conclusion : More references say that the application of fluoride before the total-etch system has a better adhesive strength than the application of fluoride before the self etch system

scholarly journals Study of dependence between microstructure and chemical composition of A32, D32, E32 grades steels at bending tests

2019 ◽  
Vol 75 (1) ◽  
pp. 57-67
Author(s):  
L. A. Ryabicheva ◽  
R. E. Velikotskii
Keyword(s):  
Tensile Strength ◽  
Science Studies ◽  
Product Yield ◽  
Negative Influence ◽  
Mechanical Tests ◽  
Bending Test ◽  
Carbon Equivalent ◽  
Metal Science ◽  
Steel Rolling ◽  
Bending Tests

Meeting the high requirements to the whole complex of mechanical characteristics is the main criteria of reliability and long service life of shipbuilding steels. To determine them it is necessary to apply modern methodologies of metal science analysis. Revelation of regularity of influence of alloying, carbon equivalent, microstructure and production technology on results of bending test of low-alloyed grades А32, D32, Е32 shipbuilding steels was the purpose of the study. Production of steel, rolling, thermal treatment, mechanical tests and metal science studies of the low-alloyed shipbuilding steels was made in Alchevsk steel-works. A quantity estimation of the D32 grade sheets microstructure was made as a result of studies, having both satisfactory and not satisfactory results of bending tests. It was determined, that stitch oxides have the most negative influence on the results of bending tests for both hot-rolled and normalized sheets. Sheets with not satisfactory results of bending tests differ from those, which passed the tests by higher value of streakiness points, particular of perlite, and in normalized condition – by higher value of Widmanstatten pattern. Sheets, which did not passed the tests, have yield strength by 5–25 MPa and tensile strength by 14–39 MPa higher, while the tensile strength was by 1.2–4.8% lower. For stable yield in bending tests within 98–100% it is necessary the tensile strength level to be not less than 30%. It is reasonably all the sheets of 10–20 mm thick out of heats with carbon equivalent higher 0.54% to subject compulsory normalization. Further increase of the sheets product yield can be achieved by decreasing of phosphor mass share and increasing of general steel purity, first of all, by decreasing of oxide inclusions

Effect of Functionalized MWCNT on the Mechanical and Dielectric Properties of PMMA Nanocomposites

2018 ◽  
Vol 18 (06) ◽  
pp. 1850035
Author(s):  
Punyapriya Mishra ◽  
Narasingh Deep ◽  
Sagarika Pradhan ◽  
Vikram G. Kamble
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Dielectric Constant ◽  
Tensile Strength ◽  
Electron Microscope ◽  
Dielectric Properties ◽  
Conductive Polymer ◽  
Mechanical Tests ◽  
Surface Structures ◽  
Scanning Electron

Carbon nanotubes (CNTs) are widely explained in fundamental blocks of nanotechnology. These CNTs exhibit much greater tensile strength than steel, even almost similar to copper, but they have higher ability to carry much higher currents, they seem to be a magical material with all these mentioned properties. In this paper, an attempt has been made to incorporate this wonder material, CNT, (with varying percentages) in polymeric matrix (Poly methyl methacrylate (PMMA)) to create a new conductive polymer composite. Various mechanical tests were carried out to evaluate its mechanical properties. The dielectric properties such as dielectric loss and dielectric constant were evaluated with the reference of temperature and frequency. The surface structures were analyzed by Scanning Electron Microscope (SEM).

Advances in measuring mechanical properties of soil in relation to soil health

2021 ◽  
pp. 215-240
Author(s):  
Muhammad Naveed ◽  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Soil Health ◽  
Indentation Test ◽  
Mechanical Tests ◽  
Confined Compression ◽  
Microstructural Stability ◽  
Rigorous Testing ◽  
The Stability ◽  
Properties Of Soil

Although mechanical properties of soil are fast and easy to measure, they have not been used as indicators of soil health apart from cone penetration resistance. The confined compression test is traditionally used for the prediction of soil compaction risks. Other mechanical tests such as soil rheometry, miniature indentation test, and tensile strength are used for assessing the impact of certain amendments on the stability of the soil. Rheological techniques are appropriate to investigate microstructural stability of soil on a particle-particle scale. Miniature indentation test is very useful to perform when mechanical properties of soil are required to measure at the mm scale. Measurement of the tensile strength of soil has an advantage as it eliminates the effect of water content. There is clearly a need for more practical and rigorous testing on comparing different mechanical properties of the soil to test how they perform relative to each other.

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