Two New Approaches to Toughness Characterization of Polyethylene

  • Author / Creator
    Cao, Wenrui
  • A new mechanistic approach is applied to characterizing toughness of low-density polyethylene (LDPE) in ductile fracture, introduced in double-edge-notched tensile (DENT) test. Three mechanisms were involved in the new approach, i.e. fracture surface formation, necking and shear plastic deformation. The specific energy density for the fracture surface formation, determined from the new approach, was found to be about 12% higher than that from the original EWF method, and the specific energy density for necking is close to that determined from simple tensile test. Ultra-high-molecular-weight polyethylene (UHMWPE) was also characterized using DENT test. However, it was found that its fracture behavior cannot be described using the original EWF method, and since necking does not occur, nor by the new mechanistic approach. As a result, a modified EWF method was developed. To justify validity of the modified EWF method, a formulation of energy balance equation was established.

  • Subjects / Keywords
  • Graduation date
    Fall 2011
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.