Comparing the Flexural Strength Values for Polymeric Material and other Fibrous Composite in 3 and 4 Point Bending Methods

Abstract

This research aims to determine the flexural strength (F.S) values for epoxy
material before the reinforcement and after it by carrying out 3and 4
bending tests then comparing the results that obtained from the two
mentioned test methods. For this purpose, the casts of materials under study
were prepared by using molds prepared previously for this objective.
Epoxy resin reinforced with chopped glass fibers with volume fraction is
(20%). After the solidification process, the samples were cut with length
(10cm), width (1cm) and thickness (0.5cm), and then some tests were
performed at room temperature. It was found from the results of tests that
epoxy reinforced with glass fibers has higher (F.S) with less strain than that
for un reinforced epoxy. It can be also noticed in 4-point bending test, the
force needed for the sample failure of pure epoxy is higher than that
required for failing the same sample subjected to 3- point bending test.
Optical microscope was used for imaging the fracture surfaces and failure
regions of samples.