Properties of Bonding Sealants in the Sealing of Cement-Based Materials

2021 ◽  
Vol 898 ◽  
pp. 19-25
Author(s):  
Adam Boháček ◽  
Jiří Šlanhof
Keyword(s):  
Tensile Test ◽  
Base Material ◽  
Fiber Material ◽  
Dust Particles ◽  
Suitable Choice ◽  
Cement Based Materials ◽  
Concrete Elements ◽  
Small Dust

This paper describes the issue of sealing cement-based materials. These materials can also include concrete elements or cement fiber boards. For the purposes of this work, a cement fiber material is selected, namely glass. This material has good effects in terms of small dust particles on the surface, which damage the bonding sealant and the substrate. Focus on its suitability for sealing cement-based substrates. The method for determining the properties of the sealant and the properties of the stylistic joint between the sealant and the base material is the tensile test. For the purpose of this test, one representative of neutral silicones, one representative of acetate silicones and one representative for acrylic sealants shall be selected. From the results of the tensile test, it is clear that with a suitable choice of the combination of bonding sealant and primer, it is possible to seal such a problematic substrate with good results.

scholarly journals Influence of Mx-Trivex, A-Skew, Three Flat Threaded and Concave Shouldered Mx-Triflute Tool Pin Profiles on Tensile Properties and Fractural Behaviour of Aa 6082-T6 Weldments During Friction Stir Welding

2020 ◽  
Vol 9 (4) ◽  
pp. 1376-1384
Keyword(s):  
Friction Stir Welding ◽  
Tensile Test ◽  
Weld Zone ◽  
Base Material ◽  
Traverse Speed ◽  
Friction Stir ◽  
Tool Pin ◽  
Solid State Joining ◽  
Joining Process ◽  
Brass Wire

Friction Stir Welding (FSW) is a topical and propitious solid-state joining process producing economical and strengthened joints of age-hardened and heat-treatable Aluminium Alloy AA 6082-T6. Mechanical and fractural behaviour of weldments were investigated in order to find crack initiation and necking on the weld zone thereby perceiving the complete behaviour of fracture occurred near the weld zone. Weldments are fabricated by employing four tool pin profiles namely MX-TRIVEX, A-SKEW, Three flat threaded and Concave shouldered MX-TRIFLUTE tools at various rotational speeds 1000 rpm, 1200 rpm and 1400 rpm at single traverse speed 25 mm/min. EXCETEX-EX-40 CNC wire cut EDM with 0.25 mm brass wire diameter has been employed to perform the extraction of tensile test specimens from the weldments according to ASTM E8M-04 standard. Tensile test was performed on elctromechanically servo controlled TUE-C-200 (UTM machine) according to ASTM B557-16 standards Maximum Ultimate Tensile Strength (UTS) of 172.33 MPa (55.5% of base material) and 0.2% Yield Stress (YS) of 134.10 MPa (51.5% of base material) were obtained by using A-SKEW at 1400 rpm, 25 mm/min and maximum % Elongation (%El) of 11.33 (113.3% of base material) was obtained at MX-TRIVEX at 1000 rpm, 25 mm/min. Minimum UTS of 131.16 MPa (42.30% of base material) and 0.2% YS of 105.207 MPa (40.46% of base material )were obtained by using Concave shouldered MX-TRIFLUTE at 1400 rpm, 25 mm/min. Minimum % El of 5.42 ( 54.2% of base material) was obtained by using A-SKEW at 1000 rpm, 25 mm/min.

Influence of Forming and Flattening on the Measured Tensile Properties of Linepipe

2006 ◽  
Author(s):  
Philippe Thibaux ◽  
Dennis Van Hoecke ◽  
Gert De Vos
Keyword(s):  
Tensile Test ◽  
Tensile Properties ◽  
Yield Stress ◽  
Mechanical Behaviour ◽  
Base Material ◽  
Constitutive Laws ◽  
Pipe Production ◽  
Model Parameters ◽  
Deformation Path ◽  
Reverse Deformation

Steelmakers are producing plates or coils, which are subsequently formed into pipes. The mechanical properties are checked after steel and pipe production, and it is commonly observed that the tensile properties of pipes differ from the properties of plate or coil. The difference in tensile properties is attributed to the forming of the pipe and the subsequent flattening of a pipe section to make a flat tensile test sample. The reverse deformation during pipe forming and flattening is expected to cause a Bauschinger effect leading to a decrease of the yield stress of the pipe compared to the yield stress of the base material. First, a kinematics description of the pipe forming is presented. This kinematics description is important to know the deformation path followed by the material during pipe forming, flattening and tensile test. Once the deformation path is known, the stress state can be computed using constitutive laws. Three constitutive laws are presented here and their ability to describe the mechanical behaviour is further discussed. To determine the mechanical behaviour in reverse deformation paths, a specific experimental set-up has been developed to make reverse tests in tension and compression. Using this experimental facility, an X60 grade on coil has been characterized. Models parameters are fitted on the experimental data. Using these model parameters, a tensile test after forming and flattening is modelled. The simulation shows that a very accurate description of material behaviour is required to predict the final tensile properties.

scholarly journals 5.3 Modeling of the Orbital Evolution of Vaporizing Dust Particles Near the Sun

1976 ◽  
Vol 31 ◽  
pp. 434-436 ◽  
Author(s):  
Zdenek Sekanina
Keyword(s):  
Interplanetary Space ◽  
Solar Radiation Pressure ◽  
Orbital Evolution ◽  
Critical Distance ◽  
Dust Particles ◽  
Dynamical Effect ◽  
The Sun ◽  
Particle Collisions ◽  
Rate Of Evaporation ◽  
Small Dust

AbstractThe Poynting-Robertson (P-R) effect (Robertson, 1937, Wyatt and Whipple, 1950), assisted by a pseudo P-R effect due to the sputtering (Whipple, 1955, 1967), is known to cause small dust particles in interplanetary space to spiral toward the sun. Evaporation from the surface of such particles thus increases progressively with time and their size is being reduced accordingly. When the rate of evaporation is no longer negligibly low, it induces on the particle a measurable dynamical effect, which is associated with the implied variations in the magnitude of solar radiation pressure relative to solar attraction. By gradually reducing solar attraction, the particle evaporation tends to increase the orbit dimensions, thus acting against P-R. The P-R inward spiraling, far exceeding the dynamical effect from evaporation at larger heliocentric distances, slows gradually down as the particle approaches the sun, and virtually ceases when the critical distance is reached, where the two forces approximately balance each other. Then, typically, the perihelion distance stabilizes, while the eccentricity starts increasing very rapidly until the particle is swept out of the solar system. This, in brief, is the orbital evolution of a vaporizing particle in the absence of other potentially important but rather poorly known processes, such as particle collisions, rotational bursting, electric charging and interactions with the solar wind and with the interplanetary magnetic field.

Laser Measurements of Fly Ash Rebound Parameters for Use in Trajectory Calculations

1987 ◽  
Vol 109 (4) ◽  
pp. 535-540 ◽  
Author(s):  
W. Tabakoff ◽  
M. F. Malak
Keyword(s):  
Gas Flow ◽  
Initial Conditions ◽  
Incidence Angle ◽  
Equations Of Motion ◽  
Solid Particles ◽  
Dust Particles ◽  
Laser Doppler Velocimeter ◽  
Laser Measurements ◽  
Flow Through ◽  
Small Dust

This paper describes an experimental method used to find particle restitution coefficients. The equations that govern the motion of solid particles suspended by a compressible gas flow through a turbomachine depend on the restitution coefficients. Analysis of the data obtained by a laser-Doppler velocimeter (LDV) system of the collision phenomenon gives the restitution ratios as a function of the incidence angle. From these ratios, the particle velocity components after collision are computed and used as the initial conditions to the solution of the governing equations of motion for particle trajectories. The erosion of metals impacted by small dust particles can be calculated by knowing the restitution coefficients. The alloy used in this investigation was 410 stainless steel.

scholarly journals Dust arcs in the region of Jupiter’s Trojan asteroids

2018 ◽  
Vol 609 ◽  
pp. A57 ◽  
Author(s):  
Xiaodong Liu ◽  
Jürgen Schmidt
Keyword(s):  
Cross Section ◽  
Size Range ◽  
Dynamical Evolution ◽  
Particle Dynamics ◽  
Dust Particles ◽  
Azimuthal Direction ◽  
Number Density ◽  
Trojan Asteroids ◽  
Two Peaks ◽  
Small Dust

Aims. The surfaces of the Trojan asteroids are steadily bombarded by interplanetary micrometeoroids, which releases ejecta of small dust particles. These particles form the faint dust arcs that are associated with asteroid clouds. Here we analyze the particle dynamics and structure of the arc in the region of the L4 Trojan asteroids. Methods. We calculate the total cross section of the L4 Trojan asteroids and the production rate of dust particles. The motion of the particles is perturbed by a variety of forces. We simulate the dynamical evolution of the dust particles, and explore the overall features of the Trojan dust arc. Results. The simulations show that the arc is mainly composed of grains in the size range 4−10 microns. Compared to the L4 Trojan asteroids, the dust arc is distributed more widely in the azimuthal direction, extending to a range of [30, 120] degrees relative to Jupiter. The peak number density does not develop at L4. There exist two peaks that are azimuthally displaced from L4.

A Scientific Proof of the Existence of God

1993 ◽  
Vol 5 (4) ◽  
pp. 1-16
Author(s):  
William S. Hatcher
Keyword(s):  
Biological Evolution ◽  
Large Mass ◽  
Physical World ◽  
Dust Particles ◽  
Nuclear Forces ◽  
Modern Physics ◽  
High Degree ◽  
Scientific Argument ◽  
Degree Of Order ◽  
Small Dust

Of the various systems that we can actually observe in the physical world, some (e.g., the movement of small dust particles suspended in the air) appear to be perfectly random (or chaotic); whereas, others (e.g., the growth of leaved plants) exhibit a high degree of order and structure. Whenever scientists encounter a phenomenon or system that exhibits a significant evolution towards order, but without any observable reason for such movement, they suspect the cause to be the objective action of some unseen force (e.g., the unseen force of gravity that, in the presence of a large mass like the earth, causes the persistent downward movement of unsupported objects). Using this method, modern physics has now validated the existence of at least four basic forces (gravity, the strong and the weak nuclear forces, and electromagnetic force), and continues to examine the possibility that other, hitherto undetected, forces may exist. In 1921 ‘Abdu’l-Bahá presented a cogent scientific argument for the existence of an objective, unseen force as the only reasonable explanation for the phenomenon of biological evolution. In the years since ‘Abdu’l-Bahá’s proof was first published, the findings of science have tended to show that, indeed, the phenomenon of evolution represents a persistent movement from disorder towards order of the kind that strongly suggests the action of some unobservable force different from all other forces so far discovered. In this article, we present a somewhat detailed reformulation of ‘Abdu’l-Bahá’s argument using certain contemporary scientific terms that were not current at the time ‘Abdu’l-Bahá wrote.

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