Kompozit Malzemelerde Yapışma Bağlantılarının Mukavemeti Üzerine Yama Fiber Takviye Açısı Etkisi
Öz
Bu çalışmada; kompozit levhalarda yapışma bağlantılarının mukavemeti üzerine yama fiber takviye açısının
etkileri deneysel yöntemlerle araştırılmıştır. [θo]8 tabakalı örgülü cam elyaf takviyeli epoksi matriks reçineli
kompozit levhalar epoksi bazlı yapıştırıcı kullanılarak birleştirilmiştir. Statik çekme deneyi ile yapılan
deneysel çalışmada yama takviye açısının, yama uzunluğunun ve yapıştırıcı kalınlığının etkileri
araştırılmıştır. Kompozit levhanın fiber takviye açısı olarak 0o ve yamanın fiber takviye açısı 0o, 15o, 30o ve
45o olarak seçilmiştir. Yama uzunluğu olarak 25.4, 38.1 ve 50.8 mm ve yapıştırıcı kalınlığı 0.2, 0.6 ve 1.0
mm olarak seçilmiştir. Bağlantı mukavemetinin yama fiber takviye açısı ile önemli oranda değiştiği
belirlenmiştir. Yama uzunluğu artışının bağlantı mukavemetini % 10 ile % 45 arasında değişen oranlarda
arttırdığı tespit edilmiştir. Çift yüzünden yapışmanın tek yüzünden yapışmaya oranla hasar yüklerini %73 ile
% 160 arası değişen oranlarda arttığı belirlenmiştir. Yapıştırıcı kalınlığının artmasına bağlı olarak ta hasar
yüklerinin %11 ile % 30 arasında değişen oranda azaldığı görülmüştür.
Anahtar Kelimeler
Patch fiber reinforced effect on the strength of adhesively bonded joints in composite plates
Abstract
In this study, the patch fiber reinforced angle effect
on the strength of adhesively bonded composite was
investigated experimentally. [θo
]8 layered composite
plates which were woven glass fiber reinforced and
epoxy resin matrix, were adhered by epoxy based
adhesive. The experimental study was realized as
static tensile test. The fiber reinforced angle of
patch, patch length and adhesive thickness were
used as a parameter.
With the developing technology of composite
materials, land, air and sea vehicles often become
the material of choice. This vehicles, light weight,
sturdiness, easy to be repaired some requirements
such as low heat conduction ability and have come
to the fore. The adhesively bonding methods are
widely used for connecting of composite plates. This
joint type was preferred as it was not have extra
weight and it was not effect of vibration. In the
literature, stress analysis of single and double joints,
joint geometry effect on the strength of joint, failure
analysis of adhesively joints, reinforcing of adhesive
effect on the joint strength and temperature and
pressure effect on the joint strength were
researched. In the studies, the mechanical properties
of adhesive, lap length, adhesive thickness and the
other geometrical changing were used as
parameters.
In this study, composite plate thickness (thc= 1.25
mm), composite plate width (w= 30 mm) and
composite plate length (L = 100 mm) were used as
fixed parameters. Also, lap length (Lap) and
adhesive thickness (tha) were changed 25.4, 38.1,
50.8 mm and 0.2, 0.6, 1.0 mm, respectively. The
fiber reinforced angle of composite plate was 0o and
the fiber reinforced angles of patch were varied 0o,15o
, 30o and 45o. The composite plates were supplied
from Izoreel Firm™ with fixed thickness and fixed
width. These plates were cut by milling machine and
later bond areas were abraded with 40 grid sand
paper. The bond surfaces were free from surface
roughness and acetone then with the help of a cotton
cloth was cleaned. The bonding processes were
realized in the special moulds. The bonded
specimens were stayed in room temperature about
15 days for curing. Then the static tensile load were
applied the specimens and the load-extension data
were recorded. The static tensile tests were realized
in 100 kN capacity Instron BS 8801 static tensile
testing machine with 0.5 mm/min cross head speed.
For reliability of experimental study, three samples
were produced for every parameter and the
experiments were realized. The failure loads were
calculated from arithmetic average of failure loads
of three samples. TYB are called samples which are
bonded to one side, while double side bonded to
ÇYB samples. The obtained results were presented
as graphs.
The failure loads were increased from 10% to 45%
with increasing of Lap length for all patch fiber
reinforced angle of TYB type joints. In the TYB type
joint, the maximum failure load was determined as
5430 N for Lap = 50.8 mm and patch reinforced
angle of 15o and the minimum failure load was
determined as 3121 N for Lap = 25.4 mm and patch
reinforced angle of 0o
. When the results are
evaluated for the patch reinforced angle, the biggest
failure loads were determined for patch reinforced
angle of 15o and the lowest failure loads were
determined for patch reinforced angle of 0o
. When
the TYB and ÇYB type joints compared with each
other, it was determined that, the failure loads was
increased from 73% to 160% varying rates. In the
ÇYB type joint, the maximum failure load was
determined as 8605 N for patch reinforced angle of
15o and the minimum failure load was determined as
6127 N for 45o
. When the thickness of adhesive was
increased, the failure loads were decreased from
11% to 30% varying rates.
Keywords
