EFFECT OF STRAIN RATE OF LOADING ON TENSILE STRENGTH AND STIFFNESS OF POLYESTER GEOGRIDS

ABSTRACTThe strain rate mechanical behavior of 12-micron long polymeric nanofibers was investigated. Experiments were carried out by a novel method that employs a MEMS-based leaf spring load cell attached to a polymeric nanofiber that is drawn with an external PZT actuator. The elongation of the fiber and the deflection of the load cell were calculated from optical microscopy images by using Digital Image Correlation (DIC) and with 65 nm resolution in fiber extension. The nanofibers were fabricated from electrospun polyacrylonitrile (PAN) with MW = 150,000 and diameters between 300-600 nm. At strain rates between 0.00025 s−1 to 0.025 s−1 the fiber ductility scaled directly with the rate of loading while the tensile strength was found to vary non-monotonically: At 0.00025 s−1 material relaxations allowed for near-uniform fiber drawing with up to 120% ductility and 120 MPa maximum tensile strength. At the two faster rates the tensile strength scaled with the rate of loading but the fiber ductility was the result of a cascade of localized deformations at nanoscale necks with relatively constant wavelength for all fiber diameters.

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Evaluating FDM Process Parameter Sensitive Mechanical Performance of Elastomers at Various Strain Rates of Loading

Materials ◽

10.3390/ma13143202 ◽

2020 ◽

Vol 13 (14) ◽

pp. 3202 ◽

Cited By ~ 1

Author(s):

Muhammad Salman Chaudhry ◽

Aleksander Czekanski

Keyword(s):

Tensile Strength ◽

High Strain Rate ◽

Strain Rate ◽

Process Parameters ◽

Mechanical Performance ◽

High Strain ◽

Influence Of Process Parameters ◽

Layer Height ◽

Fused Deposition ◽

Rate Of Loading

To optimize the mechanical performance of fused deposition modelling (FDM) fabricated parts, it is necessary to evaluate the influence of process parameters on the resulting mechanical performance. The main focus of the study was to characterize the influence of the initial process parameters on the mechanical performance of thermoplastic polyurethane under a quasi-static and high strain rate (~2500 s−1). The effects of infill percentage, layer height, and raster orientation on the mechanical properties of an FDM-fabricated part were evaluated. At a quasi-static rate of loading, layer height was found to be the most significant factor (36.5% enhancement in tensile strength). As the layer height of the sample increased from 0.1 to 0.4 mm, the resulting tensile strength sample was decreased by 36.5%. At a high-strain rate of loading, infill percentage was found to be the most critical factor influencing the mechanical strength of the sample (12.4% enhancement of compressive strength at 100% as compared to 80% infill). Furthermore, statistical analysis revealed the presence of significant interactions between the input parameters. Finally, using an artificial neural networking approach, we evaluated a regression model that related the process parameters (input factors) to the resulting strength of the samples.

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Tensile strength prediction of natural fiber and natural fiber yarn: Strain rate variation upshot

Materials Today Proceedings ◽

10.1016/j.matpr.2020.02.142 ◽

2020 ◽

Vol 27 ◽

pp. 1218-1223

Author(s):

Sagar Chokshi ◽

Piyush Gohil ◽

Amul Lalakiya ◽

Parth Patel ◽

Amit Parmar

Keyword(s):

Tensile Strength ◽

Strain Rate ◽

Natural Fiber ◽

Strength Prediction ◽

Rate Variation

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Influence of the strain rate on the tensile strength in aluminas of different purity

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:2000954 ◽

2000 ◽

Vol 10 (PR9) ◽

pp. Pr9-323-Pr9-328 ◽

Cited By ~ 2

Author(s):

F. Gálvez ◽

J. Rodriguez ◽

V. Sánchez Gálvez

Keyword(s):

Tensile Strength ◽

Strain Rate

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Tensile Properties and Fracture Behavior of SiCp/AC4CH Composite at Loading Velocities of up to 10m/s

Materials Science Forum ◽

10.4028/www.scientific.net/msf.449-452.305 ◽

2004 ◽

Vol 449-452 ◽

pp. 305-308

Author(s):

Lei Wang ◽

Toshiro Kobayashi ◽

Chun Ming Liu

Keyword(s):

Tensile Strength ◽

Ultimate Tensile Strength ◽

Yield Strength ◽

Tensile Test ◽

Strain Rate ◽

Fracture Behavior ◽

Tensile Deformation ◽

Optical Microscope ◽

Fracture Elongation ◽

Before And After

Tensile test at loading velocities up to 10 m·s-1(strain rate up to 3.2x102s-1) was carried out forr SiCp/AC4CH composite and AC4CH alloy. The microstructure of the composite before and after tensile deformation was carefully examined with both optical microscope and SEM. The experimental results demonstrated that the ultimate tensile strength (UTS) and yield strength (YS) increase with increasing loading velocity up to 10 m·s-1. Comparing with AC4CH alloy, the fracture elongation of the composite is sensitivity with the increasing strain rate. The YS of both the composite and AC4CH alloy shows more sensitive than that of the UTS with the increasing strain rate, especially in the range of strain rate higher than 102s-1.

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The effect of temperature and strain rate on the tensile strength of a fast-gas-cooled uranium-2 wt% molybdenum alloy

Journal of Nuclear Materials ◽

10.1016/0022-3115(85)90413-1 ◽

1985 ◽

Vol 132 (2) ◽

pp. 181-191 ◽

Cited By ~ 1

Author(s):

G.A.C. Boyd ◽

J. Harding ◽

P.A. Bleasdale ◽

K. Dunn ◽

G.I. Turner

Keyword(s):

Tensile Strength ◽

Strain Rate ◽

Molybdenum Alloy ◽

Effect Of Temperature

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Fracture Behavior of an AlMgMnSc Alloy at Different Temperatures

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1016.292 ◽

2021 ◽

Vol 1016 ◽

pp. 292-296

Author(s):

Yuliya Igorevna Borisova ◽

Diana Yuzbekova ◽

Anna Mogucheva

Keyword(s):

Tensile Strength ◽

Ultimate Tensile Strength ◽

Brittle Fracture ◽

Fracture Surface ◽

Strain Rate ◽

Fracture Behavior ◽

Fine Grained ◽

Angular Pressing ◽

Different Temperatures ◽

Elongation To Failure

An Al-4.57Mg-0.35Mn-0.2Sc-0.09Zr (wt. %) alloy was studied in the fine-grained state obtaining after equal channel angular pressing. The mechanical behavior of alloy at the temperatures 173 K, 298 K and 348 K and at strain rate 1×10–3 s–1 is studied. Increase of the temperature testing from 173 K to 348 K decreases the yield stress by 80 MPa, the ultimate tensile strength by 60 MPa while elongation-to failure increases by a factor of 1.4. It was found that at temperatures of 298 and 173 K, the studied alloy mainly demonstrates the mode of ductile fracture, and at a temperature of 348 K the mechanism can be described as mixed ductile-brittle fracture. It was also established that of the studied alloy is the temperature dependence of the size of the dimples on the fracture surface. The formation of smaller dimples in the samples deformed at 298 K was observed.

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Comprehensive Properties of a Novel Quaternary Sn-Bi-Sb-Ag Solder: Wettability, Interfacial Structure and Mechanical Properties

Metals ◽

10.3390/met9070791 ◽

2019 ◽

Vol 9 (7) ◽

pp. 791 ◽

Cited By ~ 1

Author(s):

Kaipeng Wang ◽

Fengjiang Wang ◽

Ying Huang ◽

Kai Qi

Keyword(s):

Tensile Strength ◽

Shear Strength ◽

Low Temperature ◽

Strain Rate ◽

Isothermal Aging ◽

Solder Joints ◽

Solder Matrix ◽

Interfacial Structure ◽

Solder Alloys ◽

Cu Substrate

Sn-58Bi eutectic solder is the most recommended low temperature Pb-free solder but is also limited from the interfacial embrittlement of Bi segregation. Since the quaternary Sn-38Bi-1.5Sb-0.7Ag solder provides a similar melting point as Sn-58Bi eutectic, this paper systematically investigated the properties of this solder from wettability, bulk tensile properties, interfacial microstructure in solder joints with a Cu substrate, interfacial evolution in joints during isothermal aging and the shear strength on ball solder joints with effect of aging conditions. The results were also compared with Sn-58Bi solder. The wettability of solder alloys was evaluated with wetting balance testing, and the quaternary Sn-38Bi-1.5Sb-0.7Ag solder had a better wettability than Sn-58Bi solder on the wetting time. Tensile tests on bulk solder alloys indicated that the quaternary Sn-38Bi-1.5Sb-0.7Ag solder had a higher tensile strength and similar elongation compared with Sn-58Bi solder due to the finely distributed SnSb and Ag3Sn intermetallics in the solder matrix. The tensile strength of solder decreased with a decrease in the strain rate and with an increase in temperature, while the elongation of solder was independent of the temperature and strain rate. When soldering with a Cu substrate, a thin Cu6Sn5 intermetallic compound (IMC) is produced at the interface in the solder joint. Measurement on IMC thickness showed that the quaternary Sn-38Bi-1.5Sb-0.7Ag had a lower IMC growth rate during the following isothermal aging. Ball shear test on solder joints illustrated that the quaternary Sn-38Bi-1.5Sb-0.7Ag solder joints had higher shear strength than Sn-58Bi solder joints. Compared with the serious deterioration on shear strength of Sn-58Bi joints from isothermal aging, the quaternary Sn-38Bi-1.5Sb-0.7Ag solder joints presented a superior high temperature stability. Therefore, the quaternary Sn-38Bi-1.5Sb-0.7Ag solder provides better performances and the possibility to replace Sn-58Bi solder to realize low temperature soldering.

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