Large deformation rate-dependent stress–strain behavior of polyurea and polyurethanes

Abstract Properties of the individual phases in a 70/30 carbon-black-loaded BR/NR blend could be successfully resolved using large deformation stress-strain modelling. Since the dispersed NR phase of the example had a lower modulus than the continuous BR phase, the interaction between the blend phases could be modelled by a simple parallel coupling arrangement. The stress behavior of each individual carbon-black-loaded polymer phase was then determined with respect to strain using a specially derived stress-strain relationship. The blend components also have to be characterized with respect to state-of-cure by empirically establishing how the parameters in the stress-strain relationship vary with respect to cure. The properties of the phases in the blend are then determined by finding the combination of component parameters which precisely reproduce the stress-strain behavior of the blend. In the demonstration example of this paper, there was evidence of a significant amount of curative migration between phases during the vulcanization process.

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Effect of Crosslink Density on Nonlinear Stress-Strain Behavior of Epoxy Glasses Subjected to Large Deformation

Journal of the Society of Materials Science Japan ◽

10.2472/jsms.62.22 ◽

2013 ◽

Vol 62 (1) ◽

pp. 22-26 ◽

Cited By ~ 3

Author(s):

Shin'ya YOSHIOKA ◽

Yuichiro YOKOYAMA

Keyword(s):

Large Deformation ◽

Crosslink Density ◽

Stress Strain ◽

Strain Behavior ◽

Nonlinear Stress

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Nonlinear Rate-Dependent Stress-Strain Behavior of Light-Weight Textile Conveyor Belt

Materials Science Forum ◽

10.4028/www.scientific.net/msf.675-677.453 ◽

2011 ◽

Vol 675-677 ◽

pp. 453-456

Author(s):

Ze Xing Wang ◽

Jin Hua Jiang ◽

Nan Liang Chen

Keyword(s):

Loading Rate ◽

Testing Machine ◽

Rate Sensitivity ◽

Sensitivity Coefficient ◽

Conveyor Belt ◽

Uniaxial Tensile ◽

Stress Strain ◽

Strain Behavior ◽

Rate Dependent ◽

Dependent Behavior

In order to investigate the effect of loading rate on the tensile performance, the uniaxial tensile experiments were conducted on universal testing machine under different loading rates (5 mm/min, 10mm/min, 50 mm/min, 100 mm/min and 150 mm/min), and a constant gage length equal to 200mm, resulting in loading strain rate of 4.17×10-4, 8.33×10-4/s, 4.17×10-3/s, 8.33×10-3/s,1.25×10-2/s, and the tensile stress-strain curves were obtained. The experimental results show that the tensile properties of the conveyor belt exhibit obvious rate-dependent behavior. In this paper, the rate sensitivity coefficient varied with loading rate, was calculated, and the nonlinear rate-dependent behavior was also investigated.

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A Model of Damage for Brittle and Ductile Adhesives in Glued Butt Joints

Technologies ◽

10.3390/technologies9010019 ◽

2021 ◽

Vol 9 (1) ◽

pp. 19

Author(s):

Maria Letizia Raffa ◽

Raffaella Rizzoni ◽

Frédéric Lebon

Keyword(s):

Adhesive Layer ◽

Imperfect Interface ◽

Interface Condition ◽

Stress Strain ◽

Butt Joints ◽

Adhesive Layers ◽

Strain Behavior ◽

Rate Dependent ◽

Torsional Loads ◽

Relative Errors

The paper presents a new analytical model for thin structural adhesives in glued tube-to-tube butt joints. The aim of this work is to provide an interface condition that allows for a suitable replacement of the adhesive layer in numerical simulations. The proposed model is a nonlinear and rate-dependent imperfect interface law that is able to accurately describe brittle and ductile stress–strain behaviors of adhesive layers under combined tensile–torsion loads. A first comparison with experimental data that were available in the literature provided promising results in terms of the reproducibility of the stress–strain behavior for pure tensile and torsional loads (the relative errors were less than 6%) and in terms of failure strains for combined tensile–torsion loads (the relative errors were less than 14%). Two main novelties are highlighted: (i) Unlike the classic spring-like interface models, this model accounts for both stress and displacement jumps, so it is suitable for soft and hard adhesive layers; (ii) unlike classic cohesive zone models, which are phenomenological, this model explicitly accounts for material and damage properties of the adhesive layer.

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