Study on Test Methods of Tensile Properties of Continuous Alumina Fiber Bundles

2021 ◽  
Vol 904 ◽  
pp. 181-187
Author(s):  
Li Li Zhang ◽  
Ji Liang Ci ◽  
Yan Ru Wang ◽  
Hua Qiong Wang ◽  
Zeng Hua Gao
Keyword(s):  
Sample Preparation ◽  
Tensile Properties ◽  
Test Methods ◽  
Gauge Length ◽  
Fiber Bundles ◽  
Curing Time ◽  
Alumina Fiber

In this paper, the effects of different sample clamping modes, curing time of the adhesive during sample preparation, gauge length of the sample and tensile rate on the tensile properties of continuous alumina fiber bundles are briefly introduced. These parameters can accurately affect the tensile properties of alumina fiber bundles.

Application of Small Punch Test to Evaluate Tensile Properties of SA213T22 Grade Boiler Steel

2015 ◽  
Vol 830-831 ◽  
pp. 191-194
Author(s):  
M. Venkateswara Rao
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Tensile Properties ◽  
Test Methods ◽  
Uniaxial Tensile ◽  
Test Results ◽  
Small Punch Test ◽  
Small Punch ◽  
Punch Test ◽  
Aging Phenomena

Conventional tensile test methods are used for service exposed high temperature boiler tubes to evaluate the deterioration in mechanical properties such as tensile strength, yield strength and percentage elongation. The mechanical properties are required to be evaluated periodically as the boiler components undergo material degradation due to aging phenomena. The aging phenomena occurs due to continuous exposure of tubes to high temperature & pressure steam prevailing inside the tubes and high temperature exposure to corrosive combustible gases from the external surfaces within the boiler.A recent developed new technique called small punch testing has been used to evaluate the tensile properties of SA 213T22 grade steel predominantly exists in super-heater and re-heater sections of boiler. The small punch tests have been carried out on the miniature disk shaped specimens of diameter of 8.0 mm and 0.5 mm thickness extracted from both the new and service exposed tubes. Conventional uniaxial tensile tests on standard specimens from the same tube material have also been performed for comparison. The service exposed tubes showed considerable loss in mechanical properties in both the conventional and small punch test results. Correlations of tensile properties have been obtained based on the comparative analysis of both small punch and uniaxial tensile test results. Further, the study showed that an appropriate empirical relation could be generated for new and service exposed materials between both the techniques. Conventional test methods require large quantity of material removal for test samples from in-service components whereas small punch test method needs only a miniature sample extraction. This small punch test technique could also be extended to evaluate the thicker section boiler components such as pipelines and headers in the boiler as a part of remaining life assessment study. Also this technique could be a useful tool to any metallic component where large quantity of sample removal may be difficult or may not be feasible.

Assessing the wear characteristics of aggregate exposed at the road surface

1998 ◽  
Vol 13 (1) ◽  
pp. 149-157
Author(s):  
A. R. Woodside ◽  
W. D. H. Woodward
Keyword(s):  
Sample Preparation ◽  
Historical Development ◽  
Test Sample ◽  
Test Methods ◽  
Road Surface ◽  
Wear Characteristics ◽  
Density Correction ◽  
The Road ◽  
Rock Types

AbstractThis paper considers the assessment of highway surfacing aggregate wear using the Aggregate Abrasion Value and micro-Deval test methods. Their historical development is discussed. The influence of test sample preparation and number of chippings assessed is compared. Data for both methods are presented for a range of rock types. Dry, wet and soaked versions of the micro-Deval test are compared. The use of a density correction to modify the micro-Deval test value is proposed. The ability of the Aggregate Abrasion Value and micro-Deval test methods to assess heterogeneous aggregates is assessed.

scholarly journals Effect of Different Hydration Time on Carbonation Degree and Strength of Steel Slag Specimens Containing Zeolite

Materials ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 3898
Author(s):  
Xiong Zhang ◽  
Jun Chang
Keyword(s):  
Compressive Strength ◽  
Steel Slag ◽  
Pozzolanic Reaction ◽  
Test Methods ◽  
New Mineral ◽  
Curing Time ◽  
Hydration Time ◽  
Carbonation Process ◽  
Substitution Ratio ◽  
Carbonation Curing

Steel slag partially substituted by zeolite (SZ) was beneficial for improving the compressive strength and carbonation degree of SZ specimens after a combined curing (hydration and then carbonation) process due to pozzolanic reaction between them. By previous work results, the zeolitic substitution ratios of 5 wt.% and 15 wt.% in steel slag specimens (SZ5 and SZ15) gained the optimum compressive strength and carbonation degree, respectively, after 1 day hydration and then 2 h carbonation. This study investigated the effect of previous hydration time (1, 3, 7, 14, and 196 days) on carbonation degree and strength of SZ specimens after subsequent carbonation curing. Two zeolitic substitution ratios (5 wt.% and 15 wt.%) were selected and pure steel slag specimens were also prepared as controls. Compressive strength results revealed that the optimum hydration curing time was 1 day and the optimum zeolitic substitution ratio was 5 wt.%. The pozzolanic reaction happened in SZ specimens was divided into early and late pozzolanic reaction. In the late hydration, a new mineral, monocarboaluminate (AFmc) was produced in SZ15 specimens, modifying the carbonation degree and strength further. And the mechanism of pozzolanic reaction in early and late hydration in SZ specimens was explained by several microscopic test methods.

Temperature and loading rate effects on tensile properties of kenaf bast fiber bundles and composites

2009 ◽  
Vol 40 (3) ◽  
pp. 189-196 ◽  
Author(s):  
Yibin Xue ◽  
Yicheng Du ◽  
Steve Elder ◽  
Kunpeng Wang ◽  
Jilei Zhang
Keyword(s):  
Tensile Properties ◽  
Loading Rate ◽  
Fiber Bundles ◽  
Bast Fiber ◽  
Rate Effects ◽  
Kenaf Bast ◽  
Kenaf Bast Fiber

The Effect of Specimen Dimensions on Obtained Tensile Properties of Sheet Metals

2009 ◽  
Vol 410-411 ◽  
pp. 481-491 ◽  
Author(s):  
Li Han ◽  
Neil Reynolds ◽  
I. Dargue ◽  
G. Williams
Keyword(s):  
Tensile Properties ◽  
Strain Curve ◽  
Gauge Length ◽  
Mapping Technique ◽  
Test Machine ◽  
Test Procedures ◽  
Strain Mapping ◽  
Aluminium Sheet ◽  
Dog Bone ◽  
2D Strain

A pilot study has been carried out to examine the effect of specimen dimensions on the obtained tensile properties of aluminium and steel sheet. The materials used were DP600 grade steel and AA5754 grade aluminium sheet. Four types of dog-bone samples with varying dimensions were tested for both materials. Standard tensile test procedures were performed using a universal test machine together with contacting extensometry. The GOM Aramis photogrammetric 2D strain mapping technique was also applied. The results suggest that for both steel and aluminium sheet materials, differing specimen dimensions have little effect on the obtained mechanical properties. Depending on the gauge length of extensometer chosen and the position at where necking occurred on the sample, the extensometry results and 2D strain mapping results slightly differed towards to the end of stress-strain curve. The failure mode between the chosen grades of steel and aluminium samples was observed to differ, as did the percentage of failures that occurred within the gauge length. All steel samples fractured across the specimen perpendicularly to the test direction; whilst fracture of aluminium samples occurred approximately 30 degrees from the perpendicular.

scholarly journals Combined Effects of Curing Temperatures and Alkaline Concrete on Tensile Properties of GFRP Bars

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Wen-rui Yang ◽  
Xiong-jun He ◽  
Kai Zhang ◽  
Yang Yang ◽  
Li Dai
Keyword(s):  
Tensile Strength ◽  
Tensile Properties ◽  
Correlation Equation ◽  
Immersion Test ◽  
Test Methods ◽  
Curing Temperature ◽  
Mechanical Degradation ◽  
Combined Effects ◽  
Scanning Calorimetry ◽  
Gfrp Bars

A significant number of studies have been conducted on the tensile properties of GFRP bars embedded in concrete under different environments. However, most of these studies have been experimentally based on the environmental immersion test after standard-curing and the lack of influence on the tensile properties of GFRP bars embedded in concrete during the curing process of concrete. This paper presents the results of the microscopic structures through scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and tensile properties of GFRP bars, which were employed to investigate the combined effects of curing temperatures and alkaline concrete on tensile properties of GFRP bars. The results showed that the higher curing temperature aggravated the influence of the alkaline concrete environment on GFRP bars but did not change the mechanisms of mechanical degradation of the GFRP bars. The influence of different curing temperatures on the tensile strength of GFRP bars was different between the bare bar and bars in concrete. Finally, the exponential correlation equation of two different test methods was established, and the attenuation ratio of the tensile strength of GFRP bars embedded in concrete under different curing temperatures was predicted by the bare test.

The Physical Properties of a Hyaluronic Acid Based Bioresorbable Membrane for the Prevention of postsurgical Adhesions

1992 ◽  
Vol 292 ◽  
Author(s):  
K. Greenawalt ◽  
L. Masi ◽  
C. Muir ◽  
J. Burns
Keyword(s):  
Hyaluronic Acid ◽  
Physical Properties ◽  
Tensile Properties ◽  
Adhesion Formation ◽  
Test Methods ◽  
Bioresorbable Membrane ◽  
Surgical Adhesions ◽  
Thin Membranes ◽  
High Degree ◽  
Sufficient Strength

AbstractWe have evaluated the physical properties and animal efficacy of a hyaluronic acid (HA) based bioresorbable membrane for the prevention of post-surgical adhesions. Test methods were developed to measure the dry and wet tensile properties and ia Xilm tissue adhesiveness of the membranes. The thin membranes were found to have sufficient strength and flexibility in the dry state for surgical handling. When hydrated in buffered saline, the membranes became weaker and more elastic. The membranes exhibited a high degree of tissue adhesiveness and significantly reduced adhesion formation in a rat cecal abrasion model.

scholarly journals Oxidation Induced Stress-Rupture of Fiber Bundles

1997 ◽  
Author(s):  
Edgar Lara-Curzio
Keyword(s):  
Fiber Bundle ◽  
Fiber Strength ◽  
Stress Rupture ◽  
Gauge Length ◽  
Fiber Bundles ◽  
Thermal Dependence ◽  
Induced Stress ◽  
Loss Of Strength ◽  
Special Case ◽  
Rupture Behavior

The effect of oxidation on the stress-rupture behavior of fiber bundles was modeled. It is shown that oxidation-induced fiber strength degradation results in the delayed failure of the associated fiber bundle and that the fiber bundle strength decreases with time as t−1/4. It is also shown that the temperature dependence of the bundle loss of strength reflects the thermal dependence of the mechanism controlling the oxidation of the fibers. The effect of gauge length on the fiber bundle strength was also analyzed. Numerical examples are presented for the special case of Nicalon™ fibers.

scholarly journals Comparative Analysis of Heavy Metal and Arsenic Content in Various Herbal Dosage Forms Marketed in Russia

2020 ◽  
Vol 10 (1) ◽  
pp. 41-50
Author(s):  
V. M. Shchukin ◽  
N. E. Kuz’mina ◽  
Yu. N. Shvetsova ◽  
A. I. Luttseva
Keyword(s):  
Sample Preparation ◽  
Inductively Coupled Plasma ◽  
Test Methods ◽  
Dosage Forms ◽  
Arsenic Content ◽  
Medicinal Products ◽  
Herbal Medicinal Products ◽  
Current Test ◽  
Herbal Medicinal ◽  
Preparation Techniques

The inclusion of requirements for independent determination of arsenic, cadmium, mercury, and lead, and the current sample preparation techniques into the State Pharmacopoeia of the Russian Federation (Ph. Rus.) requires the revision of the existing limits for elemental toxicants in herbal substances and herbal medicinal products produced from them.The aim of the study was to analyse the data on elemental toxicant content obtained during quality control of herbal substances (herbs, medicinal herb mixtures, extracts, and tinctures) using current test methods and sample preparation techniques, and to compare the obtained results with the Russian and foreign scientific and specialist literature.Materials and methods: the internal data on the content of critical heavy metals and arsenic in different dosage forms of herbal medicinal products, which were obtained by inductively coupled plasma mass spectrometry after sample preparation by decomposition in closed vessels, were compared with literature data. Results: it was demonstrated that the content of lead, cadmium, and mercury in all the test samples did not exceed the Ph. Rus. limits and was consistent with the analysed literature. The arsenic content in some herbal medicinal products was higher than the established Ph. Rus. limits, but complied with the less stringent Ph. Eur. and USP requirements for herbal substances. The authors investigated the link between the content of elemental toxicants and the place of collection and the part of the plant being tested. It was shown that different types of medicinal plants had a tendency to accumulate particular elements. The authors determined the content of the elements to be controlled in extracts and tinctures. The differences in the Russian and foreign requirements for the content of elemental toxicants may be attributed to the method of obtaining experimental data that form the basis for the setting of limits.Conclusions: the results of the study confirm the validity of the existing limits for elemental toxicants in herbal medicinal products. The authors demonstrated the need to revise the existing limits for arsenic in herbal medicinal products.

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