Rapid fracture resistance of polyethylene: dependence on polymer structure
Author(s)
Özbek, Pemra
Type
Thesis
Abstract
Polymer pipe materials being widely used in the industry for transport purposes
introduced new areas of research from mechanics of materials perspective. In this
study the effect of structural parameters on the fracture resistance of polyethylene
pipe material have been investigated via testing materials differing in their overall
structure, density, crystallinity, molecular weight, and carbon black by performing
S4 tests in addition to Instrumented Charpy, Reversed Charpy and Tensile
Tests. Furthermore, the effect of extrusion conditions have been investigated via
performing S4 Tests on pipes having differing process histories.
A new technique of analysing tensile testing enlightening plane stress resistance is
demonstrated. The stability of adiabatic drawing in a tensile test is found to be
related to the plane stress fracture resistance, which forms the basis of the RCP
resistance of a pipe. This proposed method enables the use of two basic material
properties – yield stress and strain hardening modulus – for ranking of the pipes
RCP performances, making the idea of tailor-made pipes possible.
introduced new areas of research from mechanics of materials perspective. In this
study the effect of structural parameters on the fracture resistance of polyethylene
pipe material have been investigated via testing materials differing in their overall
structure, density, crystallinity, molecular weight, and carbon black by performing
S4 tests in addition to Instrumented Charpy, Reversed Charpy and Tensile
Tests. Furthermore, the effect of extrusion conditions have been investigated via
performing S4 Tests on pipes having differing process histories.
A new technique of analysing tensile testing enlightening plane stress resistance is
demonstrated. The stability of adiabatic drawing in a tensile test is found to be
related to the plane stress fracture resistance, which forms the basis of the RCP
resistance of a pipe. This proposed method enables the use of two basic material
properties – yield stress and strain hardening modulus – for ranking of the pipes
RCP performances, making the idea of tailor-made pipes possible.
Date Issued
2008-03-31T14:59:56Z
Date Awarded
2008-02
Format Extent
13977781 bytes
Copyright Statement
Attribution NoDerivatives 4.0 International Licence (CC BY-ND)
Advisor
Leevers, Pat
Sponsor
Chevron Phillips Chemical Company
Creator
Özbek, Pemra
Publisher Department
Mechanical Engineering
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)