Effect of reducible properties of temperature, rate of strain, and filler content on the tensile yield stress of nylon 6 composites filled with ultrafine particles

Elastic/plastic stress and strain fields are obtained in a functionally graded annular disc of constant thickness subject to external pressure, followed by unloading. The elastic modulus and tensile yield stress of the disc are assumed to vary along the radius whereas the Poisson’s ratio is kept constant. The flow theory of plasticity is employed. However, it is shown that the equations of the associated flow rule, which are originally written in terms of plastic strain rate, can be integrated with respect to the time giving the corresponding equations in terms of plastic strain. This feature of the solution significantly facilitates the solution. The general solution is given for arbitrary variations of the elastic modulus and tensile yield stress along the radial coordinate. However, it is assumed that plastic yielding is initiated at the inner radius of the disc and that no other plastic region appears in the course of deformation. The solution in the plastic region at loading reduces to two ordinary differential equations. These equations are solved one by one. Unloading is assumed to be purely elastic. This assumption should be verified a posteriori. An illustrative example demonstrates the effect of the variation of the elastic modulus and tensile yield stress along the radius on the distribution of stresses and strains at the end of loading and after unloading. In this case, it is assumed that the material properties vary according to power-law functions.

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Nylon 6-rubber blends Part V The influence of the rubber content on the yield stress

Journal of Materials Science Letters ◽

10.1007/bf00418828 ◽

1993 ◽

Vol 12 (21) ◽

pp. 1678-1679 ◽

Cited By ~ 2

Author(s):

K. Dijkstra

Keyword(s):

Yield Stress ◽

Nylon 6 ◽

Rubber Content ◽

Rubber Blends

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Temperature and strain rate dependence of the tensile yield stress of PVC

Journal of Applied Polymer Science ◽

10.1002/(sici)1097-4628(19960705)61:1<109::aid-app12>3.0.co;2-2 ◽

1996 ◽

Vol 61 (1) ◽

pp. 109-117 ◽

Cited By ~ 26

Author(s):

Francisco Povolo ◽

Gustavo Schwartz ◽

Élida B. Hermida

Keyword(s):

Strain Rate ◽

Yield Stress ◽

Rate Dependence ◽

Strain Rate Dependence ◽

Tensile Yield Stress

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A new cooperative model for the prediction of compressive yield stress of polycarbonate nanocomposites considering strain rate, temperature, and agglomeration

Journal of Composite Materials ◽

10.1177/0021998319843587 ◽

2019 ◽

Vol 53 (25) ◽

pp. 3567-3575 ◽

Cited By ~ 2

Author(s):

Gholam H Majzoobi ◽

H Malek-Mohammadi ◽

J Payandehpeyman

Keyword(s):

Strain Rate ◽

Yield Stress ◽

Split Hopkinson Pressure Bar ◽

Filler Content ◽

Direct Method ◽

Current Model ◽

Testing Machine ◽

Injection Molding Process ◽

Cooperative Model ◽

Compressive Yield Stress

In this study, a new model was proposed to predict the compressive yield stress of polycarbonate nanocomposite reinforced by nanoparticles at different strain rates, temperatures, and filler contents. In addition, the proposed model makes it possible to calculate the critical filler content for which the agglomeration phenomena occur. For the validation of the model, a series of experiments were performed. At first, the modified nanoclay Cloisite 20A masterbatch was produced by a direct method using extrusion machine, and the graphene oxide masterbatch was produced by the solvent method. Then the composite samples were produced using the injection-molding process, and the compressive tests were performed at three temperatures under quasi-static and dynamic loadings using a universal testing machine and split Hopkinson pressure bar. The coefficients of the proposed modified cooperative model were calculated using the experimental results. The observations showed that the presented model could correlate the compressive yield stress of polycarbonate nanocomposites to strain rate, temperature, and filler content with sufficient accuracy. Furthermore, the agglomeration of nanoparticles in polymer matrix which is a critical issue in fabrication of the advanced nanocomposites is predictable by using the current model.

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