Properties of Hard Rubber. XIX. Effect of Temperature on Cross-Breaking Strength and Elongation

1947 ◽  
Vol 20 (2) ◽  
pp. 525-526
Author(s):  
W. H. Willott
Keyword(s):  
Breaking Strength ◽  
Testing Machine ◽  
Effect Of Temperature ◽  
Loading Test ◽  
Standard Size ◽  
Test Pieces ◽  
The Cross ◽  
Hot Weather ◽  
Electric Radiator ◽  
Usual Order

Abstract In a series of cross-breaking tests carried out on hard rubber during hot weather, the values of the breaking elongation were higher than was expected, although the cross-breaking strength was of the usual order. It was thought that the high temperature might account for these results by making the hard rubber more plastic. The following experiments were, therefore, performed to investigate the effect of small changes of temperature, such as are encountered at different times of the year, on the cross-breaking strength and elongation. Test-pieces of standard size (75 × 25 × 5 mm.) were cut from a sheet of hard rubber of the composition: 68 per cent rubber, 32 per cent sulfur, which had been vulcanized for 5 hours at 155° C. They were immersed in a beaker of water and kept at the required temperature for about 15 minutes, when they were judged to have attained a steady temperature. The tests were carried out on an Avery fabric-testing machine fitted with special clamps to give a three-point loading test, the distance between the supporting knife-edges being 50.4 mm. (2 in.). These clamps were heated to the temperature of the specimens by means of an electric radiator. The specimens were tested as soon as possible after they had been removed from the water, so that the change of temperature during the test was reduced as far as possible. The standard conditions already laid down, were observed.

Autographic Stress-Strain Curves of Rubber at Low Elongations

1930 ◽  
Vol 3 (4) ◽  
pp. 689-700 ◽  
Author(s):  
A. A. Somerville ◽  
J. M. Ball ◽  
L. A. Edland
Keyword(s):  
Relative Humidity ◽  
Test Piece ◽  
Testing Machine ◽  
Constant Speed ◽  
Effect Of Temperature ◽  
Stress Strain ◽  
Test Room ◽  
Test Pieces ◽  
Strain Data ◽  
Accurate Stress

Abstract (1) Ring or loop test pieces permit autographic records to be drawn at constant speed. (2) A longer, larger test piece permits more accurate results to be obtained. (3) The effect of temperature of the test room is most important; speed of testing machine and direction of mill or calendar grain in sample less so; effect of relative humidity is nil. (4) The 10-inch (2.5-cm.) loop test piece described gives fairly accurate stress-strain data at low elongations, which probably is within the field approaching the action of rubber goods in service.

Crack mode and life of Ti-6Al-4V under multiaxial low cycle fatigue

2015 ◽  
Author(s):  
Takamoto Itoh ◽  
Masao Sakane ◽  
Takahiro Morishita ◽  
Hiroshi Nakamura ◽  
Masahiro Takanashi
Keyword(s):  
Hollow Cylinder ◽  
Stress Ratio ◽  
Biaxial Loading ◽  
Fatigue Testing ◽  
Low Cycle Fatigue ◽  
Testing Machine ◽  
Multiaxial Fatigue ◽  
Cycle Fatigue ◽  
Loading Test ◽  
Failure Life

This paper studies multiaxial low cycle fatigue crack mode and failure life of Ti-6Al-4V. Stress controlled fatigue tests were carried out using a hollow cylinder specimen under multiaxial loadings of ?=0, 0.4, 0.5 and 1 of which stress ratio R=0 at room temperature. ? is a principal stress ratio and is defined as ?=sigmaII/sigmaI, where sigmaI and sigmaII are principal stresses of which absolute values take the largest and middle ones, respectively. Here, the test at ?=0 is a uniaxial loading test and that at ?=1 an equi-biaxial loading test. A testing machine employed is a newly developed multiaxial fatigue testing machine which can apply push-pull and reversed torsion loadings with inner pressure onto the hollow cylinder specimen. Based on the obtained results, this study discusses evaluation of the biaxial low cycle fatigue life and crack mode. Failure life is reduced with increasing ? induced by cyclic ratcheting. The crack mode is affected by the surface condition of cut-machining and the failure life depends on the crack mode in the multiaxial loading largely.

scholarly journals The State of Art on Super Structural Testing Machine in China

2017 ◽  
Vol 11 (1) ◽  
pp. 1013-1023
Author(s):  
Yubin Ma ◽  
Jinbao Ji ◽  
Weiming Yan ◽  
Jing Han
Keyword(s):  
Testing Machine ◽  
Structural Testing ◽  
Test Functions ◽  
Test Space ◽  
Test Pieces ◽  
University Of Technology ◽  
Loading System ◽  
Further Development ◽  
Test Loading ◽  
Structure Test

As important test equipment to carry out full-scale structure testing and components failure mechanisms research, super structural testing machines have developed rapidly all over the world in recent years. The authors of this paper investigated, compared and analyzed the construction and the development trends of super structural testing machines in China. The test functions, the test space, the maximum tonnage and other technical indexes of super structural testing machines, which have been built in China, were described. The functions and the typical tests of a multi-functional structure test loading system (40,000 kN) installed in the Beijing University of Technology were also discussed. The vibrations caused by the failure of brittle test pieces on this super structural testing machine were analyzed, and some suggestions to reduce the vibrations were given. It would be valuable for further development and the improvement of other super structural testing machines.

Damage Prediction of CPVC Based on Energy Method at Different Temperatures

2019 ◽  
Vol 820 ◽  
pp. 179-187
Author(s):  
Fatima Gugouch ◽  
Sara Sandabad ◽  
Nadia Mouhib ◽  
Abderrazak En-Naji ◽  
Mohamed El Ghorba
Keyword(s):  
Polyvinyl Chloride ◽  
Tensile Tests ◽  
Critical Value ◽  
Hot Water ◽  
Effect Of Temperature ◽  
Strain Variation ◽  
Damage Prediction ◽  
Test Pieces ◽  
Different Temperatures ◽  
Three Stages

The Chlorinated Polyvinyl Chloride pipes used for the supply of cold and hot water are designed and manufactured for a 50 years predictive life, but defects and harmfulness may occur during the transport process, storage and operation of tubes that significantly affect these forecasts. This work deals with the study of the mechanical behavior of Chlorinated Polyvinyl Chloride (CVPC) specimens subjected to tensile tests under the effect of temperature. Moreover, a study of damage evolution by the ultimate energy makes it possible to determine the three stages of the lifetime of the test pieces studied. On the basis of the stress-strain variation curves plotted from the experimental results, the critical value of the fraction of life corresponding to the acceleration of the damage was determined.

scholarly journals Compliance-Derived Strain Determination in Fibre (Bundle) Tests at High Temperatures

1998 ◽  
Vol 7 (3) ◽  
pp. 096369359800700 ◽  
Author(s):  
R. Paar ◽  
P. Bonnel ◽  
M. Steen
Keyword(s):  
High Temperature ◽  
High Temperatures ◽  
Strain Measurement ◽  
Fibre Bundle ◽  
Testing Machine ◽  
Tensile Tests ◽  
Gauge Length ◽  
Head Displacement ◽  
The Cross ◽  
Strain Determination

In high temperature fibre tensile tests direct strain measurement is not a straightforward task, due to the limited accessibility and the fragile nature of the specimen. A compliance method which allows to determine the true specimen strain within the gauge length from the cross head displacement of the testing machine is presented.

Effect of Temperature and Humidity on Mechanical Properties of Rabbit Hair Fibers

2012 ◽  
Vol 573-574 ◽  
pp. 1230-1234
Author(s):  
Qian Yang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strain ◽  
Breaking Strength ◽  
Great Influence ◽  
Effect Of Temperature ◽  
Breaking Force ◽  
Breaking Elongation ◽  
Different Temperatures ◽  
Hair Fiber ◽  
Fiber Processing

In this paper, it tests the mechanical properties of rabbit hair fibers in different temperatures and humidity. Contrast and analysis by experiment showed the temperature exerts a great influence on the tensile strain, breaking elongation, breaking force and breaking strength. In wetting condition, the tensile strain and breaking elongation increase, but the breaking force and breaking strength decrease. The rabbit hair fiber processing with too much water will make the structure easier to break and destroy.

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.

Effect of Temperature on the Mechanical Properties of Rubberlike Materials

1944 ◽  
Vol 17 (3) ◽  
pp. 619-620 ◽  
Author(s):  
W. P. Fletcher
Keyword(s):  
Mechanical Properties ◽  
Resonance Method ◽  
Compression Modulus ◽  
Detailed Examination ◽  
Effect Of Temperature ◽  
Plate Method ◽  
Elastic Compression ◽  
Test Pieces ◽  
Brass Plate ◽  
Rubberlike Materials

Abstract In the course of investigations into the mechanical properties of natural and synthetic rubbers intended for use in antivibration devices, variations of a large order were encountered. As these variations seemed to be largely dependent on temperature, a preliminary detailed examination in the region of 5° to 40° C was made. With the aid of a mechanical vibrator somewhat similar to that employed by Gehman, and working at 20–60 c.p.s., measurements of dynamic elastic compression modulus and associated resilience were made by the well known resonance method. A detailed description of the apparatus, method, and results is to be published later; for the present time, it may be said that the test-pieces were in the form of cylindrical rubber blocks, 0.875 inch in diameter and 0.875 inch high, bonded at each end to steel screws by the conventional brass-plate method.

Preparation and Rheological Characterization of Cross-Linked Dialdehyde Carboxymethyl Cellulose

2014 ◽  
Vol 509 ◽  
pp. 9-14 ◽  
Author(s):  
Wen Hao Li ◽  
Jun Ye ◽  
Jian Xiong
Keyword(s):  
Activation Energy ◽  
Carboxymethyl Cellulose ◽  
Loss Modulus ◽  
Periodate Oxidation ◽  
Effect Of Temperature ◽  
Molar Ratio ◽  
Rheological Characterization ◽  
Acid Media ◽  
Cross Model ◽  
The Cross

The carboxymethyl cellulose (CMC) is oxidized to the dialdehyde carboxymethyl cellulose (DACMC) at extremely acid media by sodium periodate. The reaction has been carried out at pH 2.0, temperature 35°C for 1.5h, with a NaIO4/CMC molar ratio of 1.1. FTIR peaks confirm the oxidation of CMC to DACMC. Furthermore, the rheological properties of CMC and DACMC were investigated by using steady shear and dynamic viscoelastic measurement in the range of concentrations (0.5~1 wt%). All of the CMC and DACMC solutions showed a shear thinning behavior over the shear rate at temperature from 30°C to 50°C. The zero shear viscosity (η0) was obtained by using the Cross model to fit experimental data. The η0values were used for detailed viscosity-concentration and activation energy analysis. The exponent in the viscosity-concentration power law was found to be lower than 1. The activation energy of the DACMC solution was bigger than CMCs. The effect of temperature on the storage modulus (G), the loss modulus (G) were also analyed in this study. In view of the foregoing aspects and our interest in the oxidation of carbohydrates by this oxidant, the present study is of great significant to gain some information on the cross-linked product of periodate oxidation, and is helpful for developing novel carboxymethyl polysaccharide derivatives.

A 30 ton biaxial tensile testing machine

1969 ◽  
Vol 4 (1) ◽  
pp. 22-26 ◽  
Author(s):  
H Fessler ◽  
J K Musson
Keyword(s):  
Flat Plate ◽  
Tensile Testing ◽  
Testing Machine ◽  
Tensile Testing Machine ◽  
Test Pieces ◽  
Biaxial Tensile ◽  
Form Pressure ◽  
Biaxial Tensile Testing

The machine is intended for a flat-plate testpiece, one face of which has to be unobstucted throughout the test. Plates up to 36 in long, 27 in wide, and 3/4 in thick can be accommodated. Hydraulic rams actuated by air-hydraulic pumps exert completely independent tensions on cruciform test pieces through spherical bushes. Satisfactory direct-load readings were obtained form pressure gauges.

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