Mechanical Properties in Notched AS-4/PEEK APC-2 Composite Laminates at                 Elevated Temperature

The mechanical properties and fatigue responses of Ti/APC-2 neat and nanocomposites with inclined single-edged cracks due to tensile and cyclic tests at elevated temperature were investigated. Two types of composite laminates [Ti/(0/90)s/Ti] were fabricated with and without (W/WO) nanoparticles SiO2 of optimal 1 wt.%. The geometry and dimensions of specimens were L × W × t = 240 × 25 × 1.55 mm3. The cracks were of constant length 3 mm and width 0.3 mm. The inclined angles were 0°, 45°, and 60°. Both the tensile and cyclic tests were conducted at elevated temperatures 25℃ (RT), 100℃, 125℃, and 150℃. From the tensile tests we obtained the load vs. displacement curves for both types of laminates with varied inclinations at elevated temperatures. Next, we received the applied load vs. cycles curves for the same laminates with inclined cracks at the corresponding temperature due to cyclic tests. According to the experimental data of both tensile and cyclic tests the mechanical properties, such as strength, stiffness, and life, decreased as the temperature rises. The greater the inclined angles were, the greater the strength and stiffness were. Similarly, the fatigue life was in the same trend. However, the effect of inclined angle on mechanical properties was more strong than those of temperature. The mechanical properties of nanocomposite laminates were higher than those of neat composite laminates, but not significant. The main reason was that the enhancement of spreading nano-powder silica on the laminate interfaces did not effectively eliminate the stress intensity at the crack tip locally.

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Study on the thermal and mechanical properties of novel neutron shielding composite laminates at elevated temperature

Materials Science and Engineering A ◽

10.1016/j.msea.2017.04.100 ◽

2017 ◽

Vol 697 ◽

pp. 101-110 ◽

Cited By ~ 9

Author(s):

Xue-Long Fu ◽

Yu-Bing Hu ◽

Hua-Guan Li ◽

Jie Tao

Keyword(s):

Mechanical Properties ◽

Elevated Temperature ◽

Composite Laminates ◽

Thermal And Mechanical Properties ◽

Neutron Shielding

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Mechanical Properties of a Centrally Notched APC-2 Composite Laminate Due to Fatigue Loading at Elevated Temperature (II)

Journal of Mechanics ◽

10.1017/s1727719100002707 ◽

2009 ◽

Vol 25 (3) ◽

pp. 251-259

Author(s):

M.-H. R. Jen ◽

Y.-C. Tseng

Keyword(s):

Mechanical Properties ◽

Elevated Temperature ◽

Cyclic Loading ◽

Composite Laminates ◽

Composite Laminate ◽

Stress Amplitude ◽

Fatigue Loading ◽

The Cross ◽

Applied Stresses ◽

Strain Model

AbstractThe temperature versus life (T-N) curves of both centrally notched and unnotched AS-4/PEEK (APC-2) composite laminates due to constant stress amplitude tension-tension (T-T) fatigue loading were investigated systematically. The cross-ply laminate possesses the higher mechanical properties than those of the quasi-isotropic laminate at elevated temperature, and also the mechanical properties of both lay-ups are degraded significantly as the temperature increasing. Combining both effects of notch and temperature at various normalized stresses it is found the cross-ply laminate possesses more resistance to cyclic loading than that of the quasi-isotropic laminate. Additionally, the predictive strain model is in a practical and simple form. Alternatively, the T-N curves, instead of conventionally S-N curves, at variously applied stresses are accomplished for preliminary designs and applications.

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Effect of ethanol on the mold filling-time and mechanical properties of woven glass fiber reinforced epoxy filled with TiO2 nanoparticles

Journal of Industrial Textiles ◽

10.1177/1528083720971345 ◽

2020 ◽

pp. 152808372097134

Author(s):

Sherif M Youssef ◽

M Megahed ◽

Soliman S Ali-Eldin ◽

MA Agwa

Keyword(s):

Mechanical Properties ◽

Composite Laminates ◽

Cost Effective ◽

Mold Filling ◽

High Viscosity ◽

Ansys Fluent ◽

Glass Fiber Reinforced ◽

Filling Time ◽

Ethanol Addition ◽

Woven Glass Fiber

Vacuum resin infusion (VRI) is a promising technique for manufacturing complicated structural laminates. This high viscosity of nanofilled resin increases the filling time and leads to an incomplete mold filling. The mold filling time can be reduced either by making the fiber dimensions smaller than the mold (gaps around the fibers) or by adding ethanol to nanofilled epoxy. However, ethanol addition influences the mechanical properties of composite laminates. In this study, different amounts of ethanol (0.5 wt. % and 1 wt. %) were used as a diluent to both neat epoxy and epoxy filled with (0.25 wt. %) of titanium dioxide (TiO2) nanoparticles. From results, it was found that ethanol addition saves the time for neat and nanofilled epoxy by 47.1% and 24.1%, respectively. It was found that adding 0.5 wt. % of ethanol to 0.25wt. % of TiO2 nanoparticles (GT0.25E0.5) enhances the tensile and flexural strength by 30.8% and 55.9%, respectively compared with neat specimens. Furthermore, the tensile and flexural moduli increased by 62% and 72.3%, respectively. Furthermore, the mold filling time was investigated experimentally and validated numerically using ANSYS FLUENT software. The mold filling time prediction using ANSYS FLUENT can be used to avoid resin gelation before the incomplete mold filling and thus can be considered a cost-effective methodology. The results showed that the gaps around the fibers reduce the time by 178% without affecting the mechanical properties.

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Effect of fibre content on the mechanical properties of hemp fibre woven fabrics/polypropylene composite laminates

Polymers and Polymer Composites ◽

10.1177/09673911211023942 ◽

2021 ◽

pp. 096739112110239

Author(s):

Sheedev Antony ◽

Abel Cherouat ◽

Guillaume Montay

Keyword(s):

Mechanical Properties ◽

Polymer Matrix ◽

Composite Laminates ◽

Volume Fraction ◽

Fibre Volume Fraction ◽

Fibre Volume ◽

Woven Fabrics ◽

Fibre Content ◽

Viscoelastic Behaviour ◽

Hemp Fibre

Nowadays natural fibre composites have gained great significance as reinforcements in polymer matrix composites. Composite material based on a polymer matrix reinforced with natural fibres is extensively used in industry due to their biodegradability, recyclability, low density and high specific properties. A study has been carried out here to investigate the fibre volume fraction effect of hemp fibre woven fabrics/PolyPropylene (PP) composite laminates on the tensile properties and impact hammer impact test. Initially, composite sheets were fabricated by the thermal-compression process with desired number of fabric layers to obtain composite laminates with different fibre volume fraction. Uniaxial, shear and biaxial tensile tests were performed and mechanical properties were calculated. Impact hammer test was also carried out to estimate the frequency and damping parameters of stratified composite plates. Scanning Electron Microscope (SEM) analysis was performed to observe the matrix and fibre constituent defects. Hemp fabrics/PP composite laminates exhibits viscoelastic behaviour and as the fibre volume fraction increases, the viscoelastic behaviour decreases to elastic behaviour. Due to this, the tensile strength increases as the fibre content increases. On the other hand, the natural frequency increases and damping ratio decrease as the fibre volume fraction increases.

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Effect of Elevated Temperature on Mechanical Properties of High-Volume Fly Ash-Based Geopolymer Concrete, Mortar and Paste Cured at Room Temperature

Polymers ◽

10.3390/polym13091473 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1473

Author(s):

Jun Zhao ◽

Kang Wang ◽

Shuaibin Wang ◽

Zike Wang ◽

Zhaohui Yang ◽

...

Keyword(s):

Mechanical Properties ◽

Elevated Temperature ◽

Fly Ash ◽

Residual Strength ◽

Elevated Temperatures ◽

High Volume ◽

Sem Analysis ◽

Geopolymer Concrete ◽

Ordinary Concrete ◽

Exposure Temperature

This paper presents results from experimental work on mechanical properties of geopolymer concrete, mortar and paste prepared using fly ash and blended slag. Compressive strength, splitting tensile strength and flexural strength tests were conducted on large sets of geopolymer and ordinary concrete, mortar and paste after exposure to elevated temperatures. From Thermogravimetric analyzer (TGA), X-ray diffraction (XRD), Scanning electron microscope (SEM) test results, the geopolymer exhibits excellent resistance to elevated temperature. Compressive strengths of C30, C40 and C50 geopolymer concrete, mortar and paste show incremental improvement then followed by a gradual reduction, and finally reach a relatively consistent value with an increase in exposure temperature. The higher slag content in the geopolymer reduces residual strength and the lower exposure temperature corresponding to peak residual strength. Resistance to elevated temperature of C40 geopolymer concrete, mortar and paste is better than that of ordinary concrete, mortar and paste at the same grade. XRD, TGA and SEM analysis suggests that the heat resistance of C–S–H produced using slag is lower than that of sulphoaluminate gel (quartz and mullite, etc.) produced using fly ash. This facilitates degradation of C30, C40 and C50 geopolymer after exposure to elevated temperatures.

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The Effect of Long-Term Impact of Elevated Temperature on Changes in Microstructure and Mechanical Properties of HR3C Steel

Archives of Metallurgy and Materials ◽

10.1515/amm-2016-0129 ◽

2016 ◽

Vol 61 (2) ◽

pp. 761-766 ◽

Cited By ~ 17

Author(s):

A. Zieliński ◽

M. Sroka ◽

A. Hernas ◽

M. Kremzer

Keyword(s):

Mechanical Properties ◽

Elevated Temperature ◽

X Ray ◽

Qualitative And Quantitative ◽

Microstructure And Mechanical Properties ◽

Transmission Electron ◽

Quantitative Identification ◽

Working Parameters ◽

Long Term Impact

Abstract The HR3C is a new steel for pressure components used in the construction of boilers with supercritical working parameters. In the HR3C steel, due to adding Nb and N, the compounds such as MX, CrNbN and M23C6 precipitate during service at elevated temperature, resulting in changes in mechanical properties. This paper presents the results of microstructure investigations after ageing at 650, 700 and 750 °C for 5,000 h. The microstructure investigations were carried out using scanning and transmission electron microscopy. The qualitative and quantitative identification of the existing precipitates was carried out using X-ray analysis of phase composition. The effect elevated temperature on microstructure and mechanical properties of the examined steel was described.

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Comparative Mechanical Properties of AE42 and AJ52x High-Temperature Diecast Magnesium Alloys for Elevated Temperature Applications

10.4271/2003-01-0188 ◽

2003 ◽

Cited By ~ 5

Author(s):

Pierre Labelle ◽

Don Argo ◽

Mirihban Pekguleryuz ◽

Yemi Fasoyinu ◽

Real Bouchard ◽

...

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Elevated Temperature ◽

Magnesium Alloys ◽

Temperature Applications

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Microstructure Evolution and Mechanical Properties of an Al-Cu-Mg Alloy at Elevated Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1004-1005.148 ◽

2014 ◽

Vol 1004-1005 ◽

pp. 148-153

Author(s):

Min Hao ◽

Ji Gang Ru ◽

Ming Liu ◽

Kun Zhang ◽

Liang Wang ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Elevated Temperature ◽

Elevated Temperatures ◽

Shear Fracture ◽

S Phase ◽

Mg Alloy ◽

Transmission Electron ◽

Fracture Features ◽

Scanning Electron

Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were utilized to study the microstructure and mechanical behavior of an Al-Cu-Mg alloy after tensile test at 125°C, 150°C, 175°C and 200 °C, respectively. The yield strength and ultimate tensile strength decreased with the increase of temperature, while the elongation increased firstly and then decreased. The S and S′ precipitate after tension at elevated temperatures. When the temperature was higher than 175°C, the precipitate coarsens rapidly. The alloys displayed a shear fracture features at elevated temperature. The larger S′ and S phase coarsened and dropped which forming crack in the grain boundaries and precipitate interfaces, resulting in the decrease of the elongation of the alloy.

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