Experimental Bi-axial Tensile Tests of Spinal Meningeal Tissues and Constitutive Models ComparisonBiaxial Tensile Tests of Meningeal Tissues

In recent years, the scientific community has focused its interest on innovative inorganic matrix composite materials, namely TRM (Textile Reinforced Mortar). This class of materials satisfies the need of retrofitting existing masonry buildings, by keeping the compatibility with the substrate. Different recent studies were addressed to improve the knowledge on their mechanical behaviour and some theoretical models were proposed for predicting the tensile response of TRM strips. However, this task is complex due to the heterogeneity of the constituent materials and the stress transfer mechanism developed between matrix and fabric through the interface in the cracked stage. This paper presents a state-of-the-art review on the existing constitutive models for the tensile behavior of TRM composites. Literature experimental results of tensile tests on TRM coupons are presented and compared with the most relevant analytical models proposed until now. Finally, a new experimental study is presented and its results are used to further verify the reliability of the literature expressions.

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Formability and Process Conditions of Magnesium Alloy Sheets

Materials Science Forum ◽

10.4028/www.scientific.net/msf.488-489.453 ◽

2005 ◽

Vol 488-489 ◽

pp. 453-456 ◽

Cited By ~ 11

Author(s):

Shi Hong Zhang ◽

Yong Chao Xu ◽

G. Palumbo ◽

S. Pinto ◽

Luigi Tricarico ◽

...

Keyword(s):

Deep Drawing ◽

Tensile Tests ◽

Process Conditions ◽

Drawing Ratio ◽

Temperature Range ◽

Fine Grained ◽

Axial Tensile ◽

Die Surface ◽

Lower Temperature Range ◽

Lower Temperature

Comparing the formability with each other, extrusion and various rolling experiments were carried out to make fine-grained AZ31 Mg sheets, and uni-axial tensile tests were carried out at different strain rates and temperatures to investigate the effect of different variables. A warm deep drawing tool setup with heating elements, which were distributed under the die surface and inside the blank holder, was designed and manufactured, and deep drawing was performed. Extruded Mg alloy AZ31 sheets exhibit the best deep drawing ability when working in the temperature range 250-350°C. Extruded and rolled sheets of 0.8 mm thick were also deep drawn in the lower temperature range 105-170°C，showing good formability and reaching a Limit Drawing Ratio up to 2.6 at 170°C for rolled sheets. At last, a sheet cup 0.4 mm thick was deep drawn successfully at 170 °C.

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Effect of Loading Rate on Tensile Properties of Automotive Steel Sheet

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.690-693.211 ◽

2013 ◽

Vol 690-693 ◽

pp. 211-217

Author(s):

Jin Gui Qin ◽

Fang Yun Lu ◽

Yu Liang Lin ◽

Xue Jun Wen

Keyword(s):

Strain Rate ◽

Testing Machine ◽

Structural Response ◽

Tensile Tests ◽

Dynamic Tests ◽

Static Tests ◽

Split Hopkinson Tensile Bar ◽

Axial Tensile ◽

Static Tensile ◽

Cook Model

Results of uni-axial tensile loading of three automotive steels at different strain rates (0.0011–3200s-1) are reported here. Quasi-static tensile tests were performed under the strain rate of 1.1×10-3 s-1 using an electromechanical universal testing machine, whereas dynamic tests were carried out under the strain rate in the range of 1100 to 3200 s-1 using a Split Hopkinson Tensile Bar apparatus. Based on the experimental results, the material parameters of widely used Johnson–Cook model which described the strain rate and temperature-dependent of mechanical behaviour were determined. The experiments show that strain-rate hardening is superior to thermal softening: yield stresses, tensile strength, deformation, and energy dissipation increase with the strain rate from quasi-static tests to dynamic tests. The Johnson–Cook model can describe the behaviour of these steels and provides the opportunity to study the material and structural response.

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Experimental and Numerical Investigations on Hot Deformation Behavior and Processing Maps for ASS 304 and ASS 316

High Temperature Materials and Processes ◽

10.1515/htmp-2017-0047 ◽

2018 ◽

Vol 37 (9-10) ◽

pp. 873-888 ◽

Cited By ~ 3

Author(s):

Nitin Kotkunde ◽

Hansoge Nitin Krishnamurthy ◽

Swadesh Kumar Singh ◽

Gangadhar Jella

Keyword(s):

Experimental Data ◽

Strain Rate ◽

Hot Deformation ◽

Deformation Behavior ◽

Constitutive Models ◽

Tensile Tests ◽

Uniaxial Tensile ◽

Processing Maps ◽

Hot Deformation Behavior ◽

Statistical Measures

AbstractA thorough understanding of hot deformation behavior plays a vital role in determining process parameters of hot working processes. Firstly, uniaxial tensile tests have been performed in the temperature ranges of 150 °C–600 °C and strain rate ranges of 0.0001–0.01s−1 for analyzing the deformation behavior of ASS 304 and ASS 316. The phenomenological-based constitutive models namely modified Fields–Backofen (m-FB) and Khan–Huang–Liang (KHL) have been developed. The prediction capability of these models has been verified with experimental data using various statistical measures. Analysis of statistical measures revealed KHL model has good agreement with experimental flow stress data. Through the flow stresses behavior, the processing maps are established and analyzed according to the dynamic materials model (DMM). In the processing map, the variation of the efficiency of the power dissipation is plotted as a function of temperature and strain rate. The processing maps results have been validated with experimental data.

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Anisotropy Study of Inconel 718 alloy at Sub-Zero temperatures

E3S Web of Conferences ◽

10.1051/e3sconf/202018401004 ◽

2020 ◽

Vol 184 ◽

pp. 01004

Author(s):

L Jayahari ◽

K Nagachary ◽

Chandra Ch Sharath ◽

SM Hussaini

Keyword(s):

Mechanical Properties ◽

Strain Hardening ◽

Inconel 718 ◽

Anisotropy Parameter ◽

Tensile Tests ◽

Strain Hardening Exponent ◽

Inconel 718 Alloy ◽

Normal Anisotropy ◽

Axial Tensile ◽

Forming Characteristics

There is an increase in demand for new alloys in aerospace, power generation and nuclear industries. Nickel Based super alloys are known for having distinctive properties which are best suitable for these industries. In this study Nickel based super alloy Inconel 718, is used. Over the many years of intense research and development, these alloys have seen considerable evolution in their properties and efficiency. Behaviour of materials and its forming characteristics can be precisely analysed by determining anisotropic behaviour and mechanical properties. In the present study, tried to analyse the mechanical properties of Inconel 718 like yield strength (Ys), ultimate tensile strength (UTS), strain hardening exponent (n) and strain hardening coefficient (k). Uni-axial tensile tests were conducted on specimens with various parameters such as orientations, temperature and Strain rate. Anisotropy of Inconel 718 alloy was measured based on measurable parameters. The normal anisotropy parameter (f) and planer anisotropy (Δr) were measured and observed that the anisotropy parametres are incresed with the decrease in temperature.

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Considerations for the design of polymeric biodegradable products

Journal of Polymer Engineering ◽

10.1515/polyeng-2012-0150 ◽

2013 ◽

Vol 33 (4) ◽

pp. 293-302 ◽

Cited By ~ 12

Author(s):

André C. Vieira ◽

Rui M. Guedes ◽

Volnei Tita

Keyword(s):

Experimental Data ◽

Constitutive Models ◽

Tensile Tests ◽

Failure Criteria ◽

Numerical Approach ◽

Life Cycles ◽

Strength Failure ◽

First Order Kinetics ◽

User Material Subroutine ◽

Degradation Time

Abstract Several biodegradable polymers are used in many products with short life cycles. The performance of a product is mostly conditioned by the materials selection and dimensioning. Strength, maximum strain and toughness will decrease along its degradation, and it should be enough for the predicted use. Biodegradable plastics can present short-term performances similar to conventional plastics. However, the mechanical behavior of biodegradable materials, along the degradation time, is still an unexplored subject. The maximum strength failure criteria, as a function of degradation time, have traditionally been modeled according to first order kinetics. In this work, hyperelastic constitutive models are discussed. An example of these is shown for a blend composed of poly(L-lactide) acid (PLLA) and polycaprolactone (PCL). A numerical approach using ABAQUS is presented, which can be extended to other 3D geometries. Thus, the material properties of the model proposed are automatically updated in correspondence to the degradation time, by means of a user material subroutine. The parameterization was achieved by fitting the theoretical curves with the experimental data of tensile tests made on a PLLA-PCL blend (90:10) for different degradation times. The results obtained by numerical simulations are compared to experimental data, showing a good correlation between both results.

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Crack Development in Concrete, Part 1: Fracture Experiments and CT-Scan Observations

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.385-387.69 ◽

2008 ◽

Vol 385-387 ◽

pp. 69-72 ◽

Cited By ~ 9

Author(s):

Erik Schlangen

Keyword(s):

Ct Scan ◽

Crack Path ◽

3D Structure ◽

Tensile Load ◽

Tensile Tests ◽

Crack Development ◽

3D Microstructure ◽

Axial Tensile ◽

Concrete Part

This paper describes a method to measure the 3D-microstructure of a material which can be used to perform fracture simulations. A model concrete is made and the 3D structure is obtained with a CTscanner. Uni-axial tensile tests are performed on cylindrical specimens of the model concrete a regular concrete and of a mortar. The model concrete shows more micro-cracking, a more tortuous crack path, a lower tensile load and a less brittle behaviour compared to the mortar and the regular concrete. Furthermore it is found that the opening of the crack is more uniform when the material is more heterogeneous, which results in a more stable fracture.

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Evolution of Anand Parameters With Elevated Temperature Aging for SAC Leadfree Alloys

ASME 2020 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems ◽

10.1115/ipack2020-2658 ◽

2020 ◽

Author(s):

Pradeep Lall ◽

Vikas Yadav ◽

Jeff Suhling ◽

David Locker

Keyword(s):

Experimental Data ◽

High Strain ◽

Constitutive Models ◽

Tensile Tests ◽

Model Parameters ◽

Strain Rates ◽

Automotive Electronics ◽

High Strain Rates ◽

Operating Temperatures ◽

Electronic Assemblies

Abstract Electronic equipment in automotive, agricultural and avionics applications may be subjected to temperatures in the range of −55 to 200°C during storage, operation and handling in addition to high strain-rates. Strain rates in owing to vibration and shock may range from 1–100 per sec. Temperature in electronic assemblies depends typically on location, energy dissipation and thermal architecture. Some investigators have indicated that the required operating temperature is between −40 to 200°C for automotive electronics located underhood, on engine, on transmission. Prior data indicates the evolution of mechanical properties under extended exposures to high temperatures. However, the constitutive models are often only available for pristine materials only. In this paper, effect of low operating temperatures (−65°C to 0°C) on Anand-model parameters at high strain rates (10–75 per sec) for aged SAC (SAC105 and SAC-Q) solder alloys has been studied. Stress-Strain curves have been obtained at low operating temperatures using tensile tests. The SAC leadfree solder samples were subjected to isothermal-aged up to 4-months at 50°C before testing. Anand Viscoplastic model has been used to describe the material constitutive behavior. Evolution of Anand Model parameters for SAC solder has been investigated. The computed parameters of the experimental data were used to simulate the tensile test and verified the accuracy of the model. A good correlation was found between experimental data and Anand predicted data.

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Axial tensile properties and flexibility characteristics of elementary units from multidimensional bamboo-based composites: radial and tangential moso bamboo slivers

Holzforschung ◽

10.1515/hf-2018-0017 ◽

2018 ◽

Vol 72 (9) ◽

pp. 779-787 ◽

Cited By ~ 4

Author(s):

Jianchao Deng ◽

Ge Wang

Keyword(s):

Tensile Properties ◽

Vascular Tissue ◽

Tensile Tests ◽

Fiber Saturation Point ◽

Saturation Point ◽

Central Section ◽

Elementary Unit ◽

Axial Tensile ◽

Flexural Tests

AbstractBamboo sliver (BS) is a potential elementary unit for multidimensional bamboo-based composites (MBBCs). Axial tensile and flexibility characteristics of thin radial (R) and tangential (T) BSs (BSRand BSTwith a thickness of 0.5–2.0 mm) have been studied. Axial tensile strength (AxTS) and modulus of elasticity (AxMOE) were positively correlated with the vascular tissue ratio (VTR), and the tensile properties of slices with 43–51% VTR increased more rapidly than in the VTR range of 20–36%. In axial tensile tests, cracks propagated along aVorZroute in BSR, while fibers were pulled out in the central section in case of BST. AxTS and AxMOE values increased with decreasing moisture content (MC) at 6.2–16.6% below 75°C. Flexural flexibility (FF) was enhanced with increasing MC and VTR, and the effect of MC on FF was amplified with MCs below the fiber saturation point (FSP).In situscanning electron microscope (SEM) observation during flexural tests revealed a deformation resistance of vascular tissue (VT) and the deformation disposition of parenchyma.

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Contribution of Collagen Fiber Undulation to Regional Biomechanical Properties Along Porcine Thoracic Aorta

Journal of Biomechanical Engineering ◽

10.1115/1.4029637 ◽

2015 ◽

Vol 137 (5) ◽

Cited By ~ 30

Author(s):

Shahrokh Zeinali-Davarani ◽

Yunjie Wang ◽

Ming-Jay Chow ◽

Raphaël Turcotte ◽

Yanhang Zhang

Keyword(s):

Mechanical Properties ◽

Mechanical Behavior ◽

Thoracic Aorta ◽

Aortic Wall ◽

Multiphoton Microscopy ◽

Constitutive Models ◽

Tensile Tests ◽

Biomechanical Properties ◽

Model Parameters ◽

Extracellular Matrix Components

As major extracellular matrix components, elastin, and collagen play crucial roles in regulating the mechanical properties of the aortic wall and, thus, the normal cardiovascular function. The mechanical properties of aorta, known to vary with age and multitude of diseases as well as the proximity to the heart, have been attributed to the variations in the content and architecture of wall constituents. This study is focused on the role of layer-specific collagen undulation in the variation of mechanical properties along the porcine descending thoracic aorta. Planar biaxial tensile tests are performed to characterize the hyperelastic anisotropic mechanical behavior of tissues dissected from four locations along the thoracic aorta. Multiphoton microscopy is used to image the associated regional microstructure. Exponential-based and recruitment-based constitutive models are used to account for the observed mechanical behavior while considering the aortic wall as a composite of two layers with independent properties. An elevated stiffness is observed in distal regions compared to proximal regions of thoracic aorta, consistent with sharper and earlier collagen recruitment estimated for medial and adventitial layers in the models. Multiphoton images further support our prediction that higher stiffness in distal regions is associated with less undulation in collagen fibers. Recruitment-based models further reveal that regardless of the location, collagen in the media is recruited from the onset of stretching, whereas adventitial collagen starts to engage with a delay. A parameter sensitivity analysis is performed to discriminate between the models in terms of the confidence in the estimated model parameters.

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