2.2. Preparation of composite specimen
The composite materials used for the present investigation is
fabricated by hand layup process. Chopped sisal and jute fibers of
30 mm length were used to prepare the specimen. The composite
specimen consists of total five layers in which glass fiber layers
are fixed in top middle and bottom of the specimen. Second and
fourth layers are filled by natural fibers such as sisal and jute.
The layers of fibers are fabricated by adding the required amount
of polyester resin. Initially the glass fibers polymer, jute fiber, sisal
fiber are dried in sun light to remove the moisture. The glass fiber
is mounted on the table. The glass fiber reinforced polymer is then
completely filled with polyester resin. The resin got mixed with
glass fiber reinforced polymer, which may tend to dry up within
15–20 min. Before the resin gets dried, the second layer of natural
fiber is mounted over the glass fiber reinforced polymer. The process
is repeated for jute fiber also. The polyester resin applied is
distributed to the entire surface by means of a roller. The air gaps
formed between the layers during the processing are gently
squeezed out. The processed composite is pressed hard and the excess
resin is removed and dried. Finally these specimens are taken
to the hydraulic press to force the air gap to remove any excess air
present in between the fibers and resin, and then kept for several
hours to get the perfect samples. After the composite material
get hardened completely, the composite material is taken out from the hydraulic press and rough edges are neatly cut and removed as
per the required dimensions.