The Creep Behaviour of Rubbers Reinforced with Particulate or Short Fibres
type: CreativeWork
description: Elastic stress-strain testing and (primary and secondary) creep testing have been carried out on unfilled polyurethane rubber and two rubber composites filled with 10 vol% and 20 vol% alumina particulates. They have been run at three different temperatures (20°C, 45°C and 65°C) for all three materials. The stress-strain curves of the rubber conformed well to the expectation of the conventional rubber elasticity theory. Furthermore, the true stress-strain plots of those three materials exhibited an approximately linear relationship with stiffness increasing by adding the particulates: the relationships conformed to the composite elastic theory. In order to capture the creep historical strain of these materials with an uncomplicated method, a Miller-Norton empirical formulation, which is conventionally used for predicting the creep behaviour of metal materials, is adapted in this work. The creep behaviour of all three materials could be captured well by using the Miller-Norton constitutive law and the observed dependence on temperature has been used to estimate the activation energy for creep to be ~ 7 kJ mole-1. This showed that the creep process did not involve rupture of covalent bonds (for the range of applied loads used) but was associated with physical processes such as molecular untangling. The fillers enhanced the creep resistance, to a degree that was quantitatively consistent with the expected load transfer between matrix and particulate. After these results, the particulates in polyurethane rubber were replaced by different amounts (5 vol% and 10 vol%) of alumina short fibres. The tensile stress-strain testing and the fixed load creep testing of these fibrous reinforced composite rubbers were done at the same temperatures (20°C, 45°C and 65°C). The samples were made via a blending and extrusion process that produced a degree of fibre alignment along the axial loading direction. Prior milling procedures were used to produce fibres with two different average …
abstract: Elastic stress-strain testing and (primary and secondary) creep testing have been carried out on unfilled polyurethane rubber and two rubber composites filled with 10 vol% and 20 vol% alumina particulates. They have been run at three different temperatures (20°C, 45°C and 65°C) for all three materials. The stress-strain curves of the rubber conformed well to the expectation of the conventional rubber elasticity theory. Furthermore, the true stress-strain plots of those three materials exhibited an approximately linear relationship with stiffness increasing by adding the particulates: the relationships conformed to the composite elastic theory. In order to capture the creep historical strain of these materials with an uncomplicated method, a Miller-Norton empirical formulation, which is conventionally used for predicting the creep behaviour of metal materials, is adapted in this work. The creep behaviour of all three materials could be captured well by using the Miller-Norton constitutive law and the observed dependence on temperature has been used to estimate the activation energy for creep to be ~ 7 kJ mole-1. This showed that the creep process did not involve rupture of covalent bonds (for the range of applied loads used) but was associated with physical processes such as molecular untangling. The fillers enhanced the creep resistance, to a degree that was quantitatively consistent with the expected load transfer between matrix and particulate. After these results, the particulates in polyurethane rubber were replaced by different amounts (5 vol% and 10 vol%) of alumina short fibres. The tensile stress-strain testing and the fixed load creep testing of these fibrous reinforced composite rubbers were done at the same temperatures (20°C, 45°C and 65°C). The samples were made via a blending and extrusion process that produced a degree of fibre alignment along the axial loading direction. Prior milling procedures were used to produce fibres with two different average …
author: Cui, Yi
language: eng
keywords: creep, rubber, reinforced particulate or short fibres in rubber
license: https://www.rioxx.net/licenses/all-rights-reserved/
date published: 2021-09
date modified: 2026-07-22T22:24:18Z
provider: Cambridge University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Cambridge

PropertyValue
property ID: DOI
value: 10.17863/CAM.83878