Abstract:
The experimental determination of the resistance to delamination is very important,
since composite materials have superior properties only in the fiher dircetion, The
resistance to delamination is known as the fracture toughness or fracture resistance.
Fracture toughness of a matcrial has immense importance in the determination of the
resistance of the material to crack propagation. The fracture and damage proee~~can
be influenced by many parameters, In thi~ thesis, an experimental investigation has
been carried out on the fhleture toughness of chopped strand mut glass fibre
reinforced composite aner exposing to various adverse environments, like, water,
saline water, acidic water, organic fud, ice temperature and hot air of 600C, for
different durations using single edge notched (SEN) specimcns. The specimens were
prepared from the fabricated glass fiber reinforced composite plate, The sharp notch
of different length size~, namely, 2nml, 4 mm, 6mm, \.ere ent in different specimens.
Microscopic examination has been carried out to verify unifOffillength of the notches.
'Ihe required number of speeimen~ with single edge sharp notch wa~ made in the
same \.ay.
It has been drawn a number of important inferences from this work. Fracture
toughness is independent of crack ~ize. There is a sizcahle effect of environments on
mechanical properlies and On fracture toughness. The environmental effects depend
on the type or environment, hostility, corrosivity and constilncnt ingredients. After
exposure to various envirorunents, the highe~t amount of degradation in fracture
tOliglUlCShSas bcen recorded in ucidie water and then in low temperature follewed hy
water, saline "ater, high temperature and organic fueL
A relationship between fracture toughness and duration of exposure under these
adver,;e environmeuts has been established. The fracture toughness h"" been I(mndte
decreas" continuously with increased duratien of environmental exposure, whereas
the fracture touglme.<,shas been found to be independent ofpre-naek length.