Graphical Tensile-Testing Machine for Rubber Threads

1931 ◽  
Vol 4 (3) ◽  
pp. 456-463
Author(s):  
S. H. Hahn ◽  
E. O. Dieterich
Keyword(s):  
Testing Machine ◽  
Strain Curve ◽  
Tensile Tests ◽  
Woven Fabric ◽  
Ring Test ◽  
Tensile Testing Machine ◽  
Factory Production ◽  
Physical Testing ◽  
The Common ◽  
The Many

Abstract AMONG the many types of physical testing equipment which have been designed for or applied to the needs of the rubber industry, there has never appeared an entirely satisfactory graphical machine for performing tensile tests on small rubber samples, such as the threads and tapes used in making golf balls and elastic fabrics and cords. None of the common machines can be applied directly to the testing of single threads, and even tests on pieces of dumbbell shape are quite unsatisfactory, largely because the standard machines are comparatively insensitive at low elongations and tensions and also because they depend on the personal accuracy of an operator to observe several points along the stress-strain curve. The Schopper ring test is not entirely successful for tests on threads. Accordingly it appeared that such tests on light rubber threads could best be made on a curve-drawing machine, designed and constructed especially for the purpose. In many cases, the use of any other machine would have been impossible because frequent tests had to be run on single, cut threads from factory production and on samples taken from storage or from woven fabric.

Physical Testing of Latex Films

1937 ◽  
Vol 10 (3) ◽  
pp. 584-614 ◽  
Author(s):  
C. F. Flint ◽  
W. J. S. Naunton
Keyword(s):  
Testing Machine ◽  
Water Soluble ◽  
Ring Test ◽  
Thick Sheet ◽  
Tensile Testing Machine ◽  
Test Pieces ◽  
Physical Testing ◽  
Long Time ◽  
Soluble Components ◽  
Latex Rubber

Abstract Determinations of the tensile strength of latex rubber involve difficulties which concern either the preparation of the sheets or the technic used in breaking them. Thick sheets of latex rubber may be cut into dumb-bell or ring test-pieces, which may then be broken on a tensile-testing machine of normal type. The preparation of thick sheets is, however, a matter of difficulty, owing to the fact that the complete drying-off of the water takes such a long time. Thus when ultra-accelerators are under test, vulcanization of the sheets may be advanced, or even complete, before the sheets are dry, so that investigation of the early stages of cure is impossible. Further, during the time that elapses before evaporation has gelled the whole thickness of latex, sedimentation of the compounding ingredients may occur in the mass of the fluid sheet, resulting in vulcanizates which are not uniform in composition or degree of cure. The use of devices such as porous tiles or the expedient of flowing the latex onto the surface of a gelatin jelly is objectionable because they absorb water-soluble components as well as water from the latex mix. Further, although they tend to prevent sedimentation by promoting more rapid gelling, the complete elimination of the water from a thick sheet is still a lengthy process, during which complete self-vulcanization may easily occur. The use of chemical coagulants is open to the same objection, which is of course overshadowed by the much more serious obstacle of their effect on the activity of accelerators and on the physical properties of the latex rubber.

Tensile Tests with Flat (Straight) Test-Specimens

1938 ◽  
Vol 11 (1) ◽  
pp. 214-223
Author(s):  
R. Ariano
Keyword(s):  
Test Specimen ◽  
Testing Machine ◽  
American Chemical Society ◽  
Tensile Tests ◽  
Chemical Society ◽  
Ring Test ◽  
Rubber Ring ◽  
Long Time ◽  
Fundamental Objection ◽  
Center Section

Abstract It is of course a well known fact that both ring test-specimens and flat or straight test-specimens are used in testing rubber. Ring test-specimens have for a long time been the most generally used type for testing rubber mixtures, whereas in American laboratories straight test-specimens are preferred. Ring test-specimens are the more convenient to use, but they are open to one fundamental objection, that different parts of the cross section of the rubber are elongated to different extents at any particular moment. Even straight test-specimens are not free from objectionable features. With this type of test-specimen, the inequality in the deformation at any particular instant results from the necessity of having enlarged ends for the testing machine to avoid breakage of the test-specimens in the jaws. It therefore becomes necessary to study systematically the form and dimensions of the end sections of the test-specimens and of the junction of these end sections with the central section, so that the points of rupture will not become localized in the sections in the jaws or close to these sections. As a matter of fact, an extensive investigation of this problem has been made by the Physical Testing Committee of the Rubber Division of the American Chemical Society. By a proper study of the shape of the test-specimen, it is possible to design the test-specimen so that rupture occurs in the center section and therefore so that satisfactory tensile strength measurements are obtained.

scholarly journals Research on multidimensional loading device of material mechanical test

2018 ◽  
Vol 207 ◽  
pp. 03012
Author(s):  
Guohua Zhao ◽  
Dan Wang ◽  
Liangbao Liu ◽  
Rui Fanand ◽  
Rukun Mi
Keyword(s):  
Tensile Testing ◽  
Inverse Kinematics ◽  
Parallel Mechanism ◽  
Mechanical Test ◽  
Testing Machine ◽  
Tensile Tests ◽  
Determination Method ◽  
Average Yield ◽  
Tensile Testing Machine ◽  
Loading Device

A multidimensional loading device for the material mechanical test based on Stewart Platform was proposed and manufactured in this paper. A determination method of mechanism parameters toward specific engineering requirements was analysed via inverse kinematics and contact interference boundary condition of mechanism components. A set of optimized mechanism parameters was achieved and then the pose space was obtained. Meanwhile, five repeated quasi-static standard tensile tests were performed on the multidimensional loading device and the standard tensile testing machine, respectively. The average yield strength and ultimate strength of the specimen achieved from the different testers were both merely 1.13%. Results indicated that material mechanical multidimensional loading could be conducted by the parallel mechanism.

Extensibility changes of calcified soft tissue strips from human aorta

1987 ◽  
Vol 65 (9) ◽  
pp. 1878-1883 ◽  
Author(s):  
M. H. Sherebrin ◽  
H. A. Bernans ◽  
Margot R. Roach
Keyword(s):  
Breaking Strength ◽  
True Strain ◽  
Testing Machine ◽  
High Stress ◽  
Strain Curve ◽  
Human Aorta ◽  
Stress Strain Curve ◽  
Stress Strain ◽  
Tensile Testing Machine ◽  
Calcified Tissue

Some degree of calcification was noted in more than half of the 59 aortas of individuals aged from 15 to 88 we have examined at autopsy. The calcification, which is determined by x-raying the opened and flat aorta, is in patches. We have studied the influence of calcification on stress versus strain, breaking strength, and modulus of elasticity of strips of aorta to determine its importance in vascular disease. Strips of aortic wall 5 × 30 mm were cut with orientation parallel or perpendicular to the vessel axis. Elongation versus load was measured with an Instron tensile testing machine. The true stress and true strain were calculated for both calcified and uncalcified strips from the thoracic and abdominal regions in both orientations. From the stress–strain curve the following values were selected: strain, stress, and slope at 80 mmHg equivalent pressure (1 mmHg = 133.3 Pa); maximum stress, strain, and slope; and breaking stress, strain, and slope if the sample broke. There were statistically significant differences in 13 of the 36 categories between calcified and uncalcified strips. The breaking strength and strain is lower in the calcified strips. The stress–strain curve for the uncalcified strip was mathematically transformed by reducing the amount of elongation so that the curve coincided with that of the calcified strip for eight matched pairs from the same individuals. The calcification appears to immobilize part of the strip, probably causing the boundary of the calcified tissue to be a region of high stress where tissue breakdown can occur.

Fabrication and Characterization of Micro-Patterned Magnetorheological Elastomeric Structures

2013 ◽  
Author(s):  
Ammar S. Yashaa ◽  
Souran Manoochehri
Keyword(s):  
Size Range ◽  
Testing Machine ◽  
Magnetorheological Fluid ◽  
Tensile Tests ◽  
Tensile Testing Machine ◽  
Latitudinal Patterns ◽  
Fabrication And Characterization ◽  
Low Magnetic Field ◽  
Magnetic Field Condition

This paper presents fabrication and characterization of micro-patterned magnetorheological elastomeric structures composed of magnetorheological fluid (MRF) sandwiched with magnetorheological elastomeric (MRE) materials. The MRE structures are made of polydimethylsiloxane (PMDS) with and without an additive of carbonyl iron (CI) particles with a size range of 6–9 um and the MRF is composed of silicon fluid mixed with the CI particles of the same size range. Three different SU-8 master molds of plain, longitudinal, and latitudinal patterns are constructed. Also, four MR elastomeric structures of different CI particle arrangements of isotropic MRE, anisotropic top-to-bottom-aligned MRE, anisotropic side-to-side-aligned MRE, and pure PDMS for each SU-8 master mold are fabricated. MRE structures are then characterized by using a tensile testing machine under a normal condition (off-state) and a low magnetic field condition (on-state). The tensile tests were performed to experimentally investigate their tunable properties. Later, the data gathered are compared for different conditions.

An Alternative Protocol for Determining Viscoelastic Material Properties Based on Tensile Tests Without the Use of Poisson’s Ratios

2007 ◽  
Author(s):  
Abraham Shtark ◽  
Hagay Grosbein ◽  
Guy Sameach ◽  
Harry H. Hilton
Keyword(s):  
Constitutive Relations ◽  
Testing Machine ◽  
Tensile Tests ◽  
Experimental Results ◽  
Tensile Creep ◽  
Time Interval ◽  
Tensile Testing Machine ◽  
Experimental Protocols ◽  
Poisson's Ratios ◽  
Poisson’S Ratios

Analytical and experimental protocols are formulated and outlined in detail wherein unidirectional tensile creep or relaxation experiments are performed on viscoelastic specimen. A combination of a photogrametric system and a tensile testing machine provides stress data in the loaded direction and strains in both longitudinal and transverse directions. The data is integrated through the use of the integral constitutive relations, and produce values for the creep compliance parameters. Subsequently, the viscoelastic Young’s, shear and bulk moduli are determined without the use of viscoelastic Poisson’s ratios. Experimental results indicate strong time, stress and stress history dependencies of viscoelastic PRs. Current experimental results are compared with traditional methods based on assumed time independent Poisson ratios. Maximum errors in strain values from 160% to 205% for the constant PR approach are demonstrated when its results are compared to results for the experimental time interval.

Mechanical Behavior of a Pt-Cr Jewelry Alloy Hardened by Nano-Sized Ordered Particles

2004 ◽  
Vol 842 ◽  
Author(s):  
Kamili M. Jackson ◽  
Miyelani P. Nzula ◽  
Silethelwe Nxumalo ◽  
Candace I. Lang
Keyword(s):  
Binary Systems ◽  
Cold Working ◽  
Testing Machine ◽  
Tensile Tests ◽  
Heat Treatments ◽  
Small Scale ◽  
Tensile Testing Machine ◽  
Materials Engineering ◽  
Hardness Tests ◽  
The Cost

ABSTRACTThe materials engineering of platinum jewelry is interesting because only 5wt% can be used for alloying in order to maintain hallmarking. However, pure platinum is very soft and must be alloyed in order to be used effectively as jewelry. In several binary systems an increase in hardness has been found after cold working and annealing at low temperatures. The hardening in these alloys has shown to be a result of nano-sized ordered particles. In particular, the existence of the ordered particles has previously been confirmed for a Pt-Cr alloy by TEM. Extensive work has been done on the Pt-Cr alloy to understand the crystal structure and mechanisms of the ordered phase. Hardness tests were performed to measure mechanical properties after various heat treatments. In addition, tensile tests were conducted using a small-scale tensile testing machine. An 8mm long specimen is used, which significantly reduces the cost of the specimens while providing necessary properties. Tensile tests on the Pt-Cr alloys at various post deformation heat treatments show an increase in tensile strength with no effect on ductility. They confirm results of the hardness tests while providing additional properties data. In addition, the results show a fairly good relationship between strength and hardness.

The Stress-Strain Relationship in Ebonite

1934 ◽  
Vol 7 (1) ◽  
pp. 197-211
Author(s):  
B. L. Davies
Keyword(s):  
Tensile Strength ◽  
Plastic Flow ◽  
Testing Machine ◽  
Strain Curve ◽  
Stress Strain Curve ◽  
Stress Strain ◽  
Tensile Testing Machine ◽  
Hooke’S Law ◽  
Hooke's Law ◽  
Soft Rubber

Abstract 1. A simple “extensometer” has been devised for the more accurate measurement of small elongations in hard rubber samples, thus enabling stress-strain curves to be obtained on a standard tensile testing machine. 2. The form of the curve has been described more fully than heretofore. It shows that hard rubber does not deform exactly in accordance with Hooke's Law, but exhibits plastic flow. 3. Deviations from Hooke's Law shown by the experimental curves depend upon the speed of stretching. Increased speed of elongation has been found to give higher readings of tensile strength. 4. Prolonged mastication of the rubber gives a weaker product, similar effects being obtainable by the use of a neutral softener. 5. The effects of increasing time of vulcanization have been described. The range of curves showing transition from over-cured soft rubber to ebonite indicates that the hard rubber curve is possibly related to the initial portion of the soft rubber curve. The plasticity of the overvulcanized rubber, as indicated by the deviation from Hooke's Law, increased with time of vulcanization until the “semi-ebonite” stage was reached. 6. The leather-like “semi-ebonites” differed from soft and hard rubber inasmuch as they were extremely sensitive to small changes in time of vulcanization, and inasmuch as their plasticity was such that the velocity of plastic flow was comparable with the rate of pulling (1 in. per minute), at a particular point in the test they experienced a large elongation at constant load, i. e., the velocity of flow was equal to the speed of pulling. Their plasticity decreased with further vulcanization. 7. The longest cures in the above-mentioned group gave products which were rigid at room temperature. Since these must be more resistant to shock than vulcanizates in a higher state of cure, it seems that the best technical cure of ebonite for mechanical purposes is that which gives maximum tensile strength combined with the property of undergoing considerable plastic flow (of the order of 5 per cent) at the constant maximum load, and at an arbitrarily fixed rate of stretching, the temperature being commensurate with the thermal conditions of service. Such a cure is clearly indicated by the stress-strain curve. 8. Accelerated ebonite mixings are more sensitive to time of cure than rubber-sulfur stocks without accelerators. An accelerator may produce very little effect on the tensile strength and breaking elongation, but may yield a stock which “scorches” readily. This prevulcanization was detrimental to the mechanical properties of the vulcanizate, even though it was so slight that its presence was not detected during normal processing. 9. Mineral rubber in ebonite stocks has been shown to accelerate the cure as indicated by the stress-strain curve. 10. Stocks containing high loadings of gas black gave vulcanizates which were weak and brittle. The effect of the black on the stiffness was similar to that produced by further cure. 11. The stress-strain curve provides a reliable means whereby stocks containing different accelerators and other compounding ingredients may be compared at equivalent states of vulcanization.

scholarly journals Effect of Nanometric Metallic Hydroxides on the Flame Retardant Properties of HDPE Composites

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
F. I. Beltrán-Ramírez ◽  
L. F. Ramos-deValle ◽  
E. Ramírez-Vargas ◽  
S. Sánchez-Valdes ◽  
A. B. Espinoza-Martínez ◽  
...  
Keyword(s):  
Flame Retardant ◽  
Tensile Properties ◽  
Cone Calorimeter ◽  
Flame Retardants ◽  
Testing Machine ◽  
Tensile Tests ◽  
Tensile Testing Machine ◽  
Cone Calorimeter Test ◽  
Ul 94 ◽  
Flame Retardant Properties

The effect of nanometric magnesium and aluminum hydroxides on the flame retardancy of high density polyethylene was studied. Additionally, the effect of maleic anhydride grafted polyethylene (PEgMA) and methyl acrylate grafted polyethylene (EMA) compatibilizers, on the tensile properties, was also studied. Morphological characterization of nanocomposites was carried out by means of scanning transmission electron microscopy (STEM). Flame retardant properties of nanocomposites were evaluated by the UL-94 horizontal and vertical tests as well as by cone calorimeter tests. Thermal degradation behavior was analyzed with a thermogravimetric analyzer (TGA). Tensile tests were carried out according to ASTM D 638-03 in an Instron 4301 tensile testing machine. From STEM images, a good dispersion of flame retardants (MH and ATH) in the polymer matrix was observed, which was reflected in the flame retardant properties. Results showed that the combination of nanometric MH and ATH produced excellent flame retardant properties, achieving a classification of V0 in the UL-94-V test and producing the lowest peak of heat release rate (PHRR) and the lowest total heat released (THR) in the cone calorimeter test. Finally, the addition of compatibilizer, especially PEgMA, resulted in much better tensile properties as compared to the noncompatibilized composition, maintaining the flame retardant properties.

scholarly journals Stress-Strain Behavior – Deformation Degree Relationship Investigation of Alloy CrNi60WTi

2021 ◽  
Vol 65 (1) ◽  
pp. 105-107
Author(s):  
Yaroslav Kosmatskiy ◽  
Nikolai Fokin ◽  
Kseniya Yakovleva ◽  
Vladislav Nikolenko ◽  
Boris Barichko ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Cold Deformation ◽  
Testing Machine ◽  
Tensile Tests ◽  
Outer Diameter ◽  
Test Results ◽  
Deformation Degree ◽  
Tensile Testing Machine ◽  
Strain Behavior ◽  
Static Tensile

The article presents the results of a research of the dependence of the mechanical properties of the CrNi60WTi alloy on the degree of cold deformation. As part of the study, five samples were taken from a pipe with an outer diameter of 89.0 mm and a wall thickness of 11.0 mm. The samples were cold-deformed to varying degrees and static tensile tests were performed on an SSI MTSInsight tensile testing machine. Based on the test results, the dependences of the mechanical properties on the degree of cold deformation were calculated.

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