A Rugged Semiautomatic Extensometer for Rubber

1963 ◽  
Vol 36 (1) ◽  
pp. 68-74 ◽  
Author(s):  
P. I. Donnelly
Keyword(s):  
Tensile Strength ◽  
Tensile Properties ◽  
Tensile Testing ◽  
Electrical Circuit ◽  
Optimum Conditions ◽  
Routine Testing ◽  
Vulcanized Rubber ◽  
Poly Vinyl Chloride ◽  
Digital Indication ◽  
Soft Rubber

Abstract The evaluation of an elastomer—new or established—inevitably involves a study of tensile properties. ASTM procedure D 412 is generally used as a guide for the tensile testing of vulcanized rubber. In this method, an operator observes bench marks on the sample and records the modulus at every 100% elongation, the ultimate elongation, and the tensile strength at break. An extensometer has been developed to eliminate operator coordination and judgment factors from rubber tensile testing. It is simple and sufficiently rugged for routine testing. Its features are a counterbalanced guide rod with a sliding electrical contactor, and specimen followers which automatically unlatch to avoid being damaged when specimens break. In addition there is a counter for direct digital indication of elongation, and an electrical circuit which controls a short duration spark to mark the autographic chart. Experience in testing up to 5000 specimens per year has shown that the apparatus makes an inexperienced operator as effective as trained operators working under optimum conditions. The instrument has been used successfully on materials ranging from soft rubber to plasticized and filled poly (vinyl chloride).

Determination of Tensile Properties of Hemp-Fiber Bundle by Using Tensile Testing Equipment with Raspberry Pi

2014 ◽  
Vol 931-932 ◽  
pp. 1308-1312
Author(s):  
Paiboon Limpitipanich ◽  
Anucha Promwungkwa
Keyword(s):  
Tensile Strength ◽  
Tensile Properties ◽  
Fiber Bundle ◽  
Tensile Testing ◽  
Credit Card ◽  
Testing Machine ◽  
Tensile Load ◽  
Testing Equipment ◽  
Raspberry Pi ◽  
Hemp Fiber

Tensile strength of some natural fibers such as hemp is higher than that of steel. To determine tensile properties of hemp fiber, a fiber or bundle is tensile tested with universal testing machine that is controlled by personal computer. This paper presents a small tensile testing equipment that is controlled by Raspberry Pi (RPi), a credit-card-sized single-board computer. General Purpose Input Output (GPIO) pins on RPi were used for controlling the machine crosshead and receiving the tensile load that apply to a hemp bundle. A stepper motor was used to drive the crosshead. Tensile load was measured by using a load measurement system included load-cell, instrument amplifier, and analog-to-digital converter. The applied load and extension were real-time displayed and continuously recorded throughout the test. Testing hemp-fiber bundles with the proposed equipment found that their tensile strength and Youngs modulus were 446.75±184.36 MPa and 18.23±8.26 GPa, respectively. These results were in good agreement with the properties founded in other publications. Test results also found that hemp-fiber bundle with smaller diameter showed higher tensile strength than that of larger one.

Influence of Hydroxyl and Carboxyl Functionalized Multi-Walled Carbon Nanotube and Filler Loading on the Tensile Properties of Epoxy Composites

2017 ◽  
Vol 264 ◽  
pp. 58-61
Author(s):  
Ervina Junaidi ◽  
Mariatti Jaafar ◽  
Sinin Hamdan
Keyword(s):  
Tensile Strength ◽  
Carbon Nanotube ◽  
Tensile Properties ◽  
Tensile Testing ◽  
Morphological Analysis ◽  
Tensile Modulus ◽  
Filler Loading ◽  
Epoxy Composites ◽  
Slight Improvement ◽  
Multi Walled Carbon Nanotube

In this study, three various types of fillers; pristine multi-walled carbon nanotube (MWCNT), hydroxyl functionalized multi-walled carbon nanotube (MWCNT-OH) and carboxyl functionalized multi-walled carbon nanotube (MWCNT-COOH) were used to prepare epoxy (EP) composites via ultrasonication and casting techniques. The effect of pristine MWCNT and functionalized MWCNT (MWCNT-OH and MWCNT-COOH) and fillers loading (0-1.0 vol%) on tensile properties of EP composites were investigated and compared. To identify the effectiveness of functional groups on the EP composites, the MWCNT, MWCNT-OH and MWCNT-COOH were compared through tensile testing. The addition of pristine MWCNT decreased the material’s tensile strength and modulus, while the addition of MWCNT-OH decreased the material’s tensile strength. However, among the EP composites, the 0.4 vol% MWCNT-COOH/EP composite exhibited a 12.80% increase in tensile strength (44 MPa). The tensile modulus of 0.4 vol% MWCNT-OH/EP and MWCNT-COOH/EP composites were found to be significantly higher compared to unfilled epoxy which were approximately 15.60% (2376 MPa) and 18.54% (2436 MPa) respectively. In conclusion, the MWCNT-COOH/EP composite showed slight improvement in both the tensile strength and modulus. The effect of functionalized MWCNT was supported by morphological analysis, which demonstrated an improvement in MWCNT-COOH dispersion with slightly fine agglomerates particles at 0.4 vol%.

Study on the Tensile Testing Method of p-Phenylene Terephthalamid (PPTA) Fibers for Ballistic Protection

2012 ◽  
Vol 591-593 ◽  
pp. 989-992
Author(s):  
Xian Cong Huang ◽  
Hong Zhou ◽  
Yan Li ◽  
Chang Sheng Li ◽  
Yi Jiang
Keyword(s):  
Tensile Strength ◽  
Tensile Properties ◽  
Performance Index ◽  
Tensile Testing ◽  
Loading Rate ◽  
Strength Index ◽  
Ballistic Performance ◽  
Testing Method ◽  
Ballistic Protection

The purpose of this work is to study the effect of testing method on the tensile properties index of p-Phenylene terephthalamid (PPTA) fibers. Three different brand fibers were employed, namely Kevlar 129, Twaron and Heracon. The results indicate that tensile strength index is strongly affected by gauge and twist coefficient, while the influence of loading rate is minor. The ballistic performance is also evaluated according to a proposed ballistic performance index U*. The results indicated that ballistic performance is strongly affected by twist coefficient

Semi-Ebonite. Part 1

1935 ◽  
Vol 8 (4) ◽  
pp. 554-570 ◽  
Author(s):  
P. A. Gibbons
Keyword(s):  
Tensile Strength ◽  
Plastic Flow ◽  
Room Temperature ◽  
Constant Load ◽  
Vulcanized Rubber ◽  
Large Elongation ◽  
Soft Rubber

Abstract Hitherto two products of the reaction between sulfur and rubber have been studied and used commercially, soft rubber and ebonite. Few publications have appeared concerning the products obtained by vulcanization of proportions between 5 and 30 parts of sulfur with 100 parts of rubber. Before the introduction of organic accelerators of vulcanization the coefficient of vulcanization was considered a satisfactory criterion of the quality of soft vulcanized rubber. Mixes of rubber and sulfur vulcanized to a coefficient of more than 3.5 to 4 were usually considered overvulcanized in that experience showed that the optimum properties as regards tensile strength and elongation at rupture occurred at this degree of vulcanization. Semi-ebonites differ from soft rubber and ebonite in as much as they are extremely sensitive to small changes in the time of vulcanization. Their plasticity is such that the velocity of plastic flow just prior to break is relatively great, and thus they may experience a large elongation at constant load. Their plasticity decreases with further vulcanization, in fact, with advance in vulcanization they become almost rigid at room temperature. The decrease in plastic flow is accompanied by an increase in hardness and brittleness and the ultimate stage in the rubber-sulfur reaction, ebonite, is reached.

Prediction of Tensile Properties Based on Hardness Measurement

2014 ◽  
Vol 606 ◽  
pp. 35-38 ◽  
Author(s):  
Pavol Zubko ◽  
Ladislav Pešek
Keyword(s):  
Tensile Strength ◽  
Yield Strength ◽  
Tensile Properties ◽  
Tensile Testing ◽  
Brinell Hardness ◽  
Hardness Measurement ◽  
Stress Strain ◽  
Hardness Values ◽  
Hollomon Equation ◽  
Good Agreement

The contribution deals with prediction of tensile properties based on measurement of microhardness. First of all, the database of stress strain, s-e vs. hardness data was created. Tensile strength, yield strength, ductility and parameters of Ludwig-Hollomon equation σ = σ0+kεn; k, n were correlated with hardness. Various hardness values found in literature were recalculated to Brinell hardness. In tensile testing measured s-e curves were compared with that obtained from the correlation. The investigated materials were API 5 L grade steels X70 after different deformation exposition. The results give good agreement between compared data. The most difference between estimated and measured curve is in area of yield strength, because of Lüders deformation on investigated steel.

The Effect of Temperature on the Tensile Properties of Steel 0Cr18Ni9

2010 ◽  
Vol 654-656 ◽  
pp. 194-197
Author(s):  
Wei Fen Li ◽  
Wei Niu ◽  
Zhi Ming Hao ◽  
Ming Hai Li
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Yield Strength ◽  
Tensile Properties ◽  
Tensile Testing ◽  
Testing Machine ◽  
Effect Of Temperature ◽  
Tensile Testing Machine ◽  
Increasing Temperature

Experiments of tensile mechanical properties of steel 0Cr18Ni9 are done on the MTS 810 tensile testing machine, and the temperature range is from 20°C to 1200°C. The stress vs. strain curves are obtained. Results show that the elastic modulus, yield stress and tensile strength decrease with increasing temperature .Based on the experiment results, the functions of the elastic modulus, yield strength and tensile strength versus temperature are represented by polynomial.

The Influence of the Test-Specimen on the Results Obtained In Tensile Tests of Soft Vulcanized Rubber Mixtures

1953 ◽  
Vol 26 (2) ◽  
pp. 465-480
Author(s):  
R. Herzog ◽  
R. H. Burton
Keyword(s):  
Natural Rubber ◽  
Tensile Properties ◽  
Test Specimen ◽  
Tensile Tests ◽  
Stress Strain ◽  
Vulcanized Rubber ◽  
Different Types ◽  
Small Test ◽  
Soft Rubber

Abstract The small test-specimen of the VSM-1 type should not be used for measuring the tensile properties of pure-gum vulcanizates; instead, the VSM-1a type of test-specimen should be used for such vulcanizates. Results obtained with the different types of test-specimen differ greatly; hence, in reporting the results of any tests of this kind, the type of test-specimen used should be stated, and only results obtained with one particular type of test-specimen should be compared. For example, substitution of the VSM-2 type of test-specimen by the KTA-II type of test-specimen, which is of approxmately the same size, unfortunately does not result in any better agreement. Based on these differences, which in the case of natural rubber have been found to vary from one type of vulcanizate to another, it is natural to expect corresponding unpredictable differences with various synthetic elastomers. The determination of stress-strain properties of soft rubber vulcanizates is, therefore, fundamentally a problem of agreement on methods of testing, i.e., of standardization.

scholarly journals The Effect of Fiber Length on Tensile Properties of Polyester Resin Composites Reinforced by the Fibers of Sansevieria trifasciata

2014 ◽  
Vol 8 ◽  
pp. 7-13 ◽  
Author(s):  
Palla Hari Sankar ◽  
Y.V. Mohana Reddy ◽  
K. Hemachandra Reddy ◽  
M. Ashok Kumar ◽  
A. Ramesh
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Tensile Properties ◽  
Tensile Testing ◽  
Fiber Length ◽  
Polyester Resin ◽  
Resin Composites ◽  
Elongation At Break ◽  
Polyester Composites ◽  
Scanning Electron

This paper presents the study of the tensile properties of Sansevieria trifasciata – fiber (here after called STF) reinforced polyester composites. The composite sample was fabricated with five different fiber lengths of STF (2, 4, 6, 8 and 10 mm). The fabrication was made by hand lay-up technique. Mechanical properties were determined using tensile testing. An interact between fiber and matrix was observed from the SEM (scanning electron microscope) micrographs. The study reveals that the tensile strength increased with fiber length without effecting the elongation at break of the composite.

Characterization of photocatalytic composite nanofiber yarns with respect to their tensile properties

2016 ◽  
Vol 47 (5) ◽  
pp. 921-937
Author(s):  
Farnaz Memarian ◽  
Mohammad Amani Tehran ◽  
Masoud Latifi
Keyword(s):  
Tensile Strength ◽  
Tensile Properties ◽  
Testing Machine ◽  
Water Remediation ◽  
Diameter Distribution ◽  
Optimum Conditions ◽  
Nanofiber Yarn ◽  
Electrospinning Method ◽  
Composite Nanofiber

In this paper, nylon 66/TiO2 composite nanofiber yarn has been developed using electrospinning method. The effect of the TiO2 nanoparticle content on the physical and tensile properties of the resulted composite nanofiber yarns has been extensively investigated using SEM, EDX, FTIR and mechanical testing machine. The probability density function is computed to model the diameter distribution of nanofibers constituent of the composite yarn for different percentages of TiO2. The addition of TiO2 nanoparticles into the electrospun composite nanofiber yarn decreases its tensile strength. The influence of thickness (diameter) and twist of the yarn on its tensile strength has been considered and the optimum conditions with improved tensile strength have been presented. Photoactivity of the composite yarns is tested against Rhodamine B (RhB). Results show that nanocomposite yarns are effective to be used as an economically and environmentally friendly photocatalyst in water remediation processes. They are not dispersed in the solution and can be removed easily without additional and costly steps of filtration or centrifuge.

Increased Suture Embedment in Tendons: An Effective Method to Improve Repair Strength

2002 ◽  
Vol 27 (4) ◽  
pp. 333-336 ◽  
Author(s):  
B. WANG ◽  
J. B. TANG
Keyword(s):  
Tensile Strength ◽  
Tensile Properties ◽  
Ultimate Strength ◽  
Tensile Testing ◽  
Testing Machine ◽  
Gap Formation ◽  
Tensile Testing Machine ◽  
Flexor Tendons ◽  
Important Contributor ◽  
Complete Failure

We evaluated the effect of length of suture embedment within tendons on the tensile strength of repaired tendons. Thirty fresh pig flexor tendons were divided into three groups and subjected to repairs with the Halsted tendon sutures in which 1/3, 1/2, and 2/3 of the length of the longitudinal sutures was embedded within the tendons. The repaired tendons were pulled to complete failure by an Instron tensile testing machine. The 2 mm gap-formation force, ultimate strength, stiffness, and energy to failure were greatest when 2/3 of the suture length was embedded within the tendon. The results indicate that suture embedment is an important contributor to the tensile properties of the repair, and that increase in length of suture embedment is an effective way to strengthen tendon repairs.

Sign in / Sign up

Export Citation Format

Share Document