Study of Ligament Length Effect on Mode Mix of a Modified In-Plane Shear Test Specimen

Study of Ligament Length Effect on Mode Mix of a Modified In-Plane Shear Test Specimen

ABSTRACT

Shear fracture toughness is an important material behavior that needs to be determined and considered in many industrial fields. At the same time, shear testing is one of the complex material testing areas where available methods are few, often need special arrangements, and most of the methods do not strictly satisfy the definition of pure shear. In this study, a modified shear test specimen was proposed to measure the shear fracture toughness by uniaxial loading in a tensile testing machine. High density polyethylene (HDPE) was used as test material for the experiments. The specimen was created in order to suit the most common used tensile test machine. The specimen was then optimized by using finite element analysis (FEA) to find the geometry and the size of the pre-notch to avoid the mixed mode loading and minimize effects of normal stresses. For the specimen in discussion, an upper and lower limit of usable ligament length can be found. A method for determining the fracture toughness was discussed according to the essential work of fracture. Finally, an example of a special application of the proposed specimen was presented where the variation of shear strength of controlled delamination material (CDM) was measured.

KEYWORDS

shear test specimen, polymers, fracture toughness, finite element simulation

CITATION

Islam, M. S., Kao-Walter, S., and Yang, G., “Study of Ligament Length Effect on Mode Mix of a Modified In-Plane Shear Test Specimen,” Materials Performance and Characterization, ISSN 2165-3992. DOI: 10.1520/MPC20150058

DOWNLOAD

http://urn.kb.se/resolve?urn=urn:nbn:se:bth-12998

Categories: Publications, Research