الفهرس 
INTRODUCTION.Only 14 pages are availabe for public view
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Abstract
The main observations and findings of the present study may be summarized on
the following :-
1- A general trend of decrease in friction traction as contact load and speed
increase has been observed for all the three composites.
The high level of friction tractions was recorded for material C, where’s material
A showed the lowest trend.Materials 8 and C indicated a sensitivity to the
applied contact load rather than material A which showed a DROP in friction
followed by a substantial increase, especially at speeds 4.6 and 6.7m/s.
2- A general decrease in friction coefficient as sliding speed increases was
observed.
from the comparison of the three materials, it has been found that, material C
showed the highest values of friction traction, whilst, material 8 gave the
lowest. Material A was found to be sensitive to the sliding speed changes.
The decrease of friction with both load and speed reduces the ability of
using such materials in places, where high levels of braking or
transmitting loads should be essential.
3- A general trend of friction coefficient decrease with frictional heat
increase has been observed up to about 50kj, followed by an equlllbrium
region nearly between 50kj and 80kj, then unsubstantial increase in friction
coefficient has been recorded after 80kj
4- For composite material 8 the fluctuations of friction coefficient with time is
unnoticeable, however, for material A and C no fluctuations in friction
coefficient with time have been observed
5- Moreover, a decrease in Friction coefficient was observed as applied
load increase for all temperatures.
High friction coefficient values were recorded for B. Iow values of
friction traction were observed for material C, whilst material A gave
nearly the modest friction behavior for all temperature ranges.
6- Considering the contact temperature effects, it has been observed that an
initial decrease in coefficient of friction as surface temperature increase was