الفهرس 
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Abstract
The experimental program was divided into three phases, the first phase
regarding the synthesizing of Copper-Nickel ferrites nanoparticles using suitable
local materials and by applying simple laboratory operations. To make sure that
the output conformed to the required, it was analyzed using X-ray diffraction
(XRD) and X-ray Fluorescence (XRF). The Transmission Electron Microscopy
(TEM) was used to determine the shape of the resulting nanoparticles. This
nanoparticle was used as an addition in the cement mortar as a replacement
percentage of cement weight in the second phase.
The second phase regarding the determination of the best ratio of
nanoparticles as addition to the ordinary Portland cement mortar which give the
best compressive strength. To do that, more than fourteen trial mixes were
produced and more than 120 mortar cubes were cast (70x70x70mm). The mix
design of ordinary Portland cement mortar used contains, sand: cement ratio of
2:1 and water: cement ratio was 0.35.Percentage 0.07% cement wt of high range
water reducer was used (Gellenium sky 315- super plasticizer from PASF).
Also, 15% cement wt was silica fume. The synthesized nano fibers were added
to the mix by ratio between (0.04–3) percent using trial and error method.
In the third phase, the main objective was studying the behavior of the
composites by casting and testing small model of columns having the
dimensions of (30x30x300mm), beams (30X60X50mm) and plates
(15X250X500mm). After 28 days, the specimens were painted with white paint
to facilitate the crack detection during testing process. A set of four “demec”
points was placed on one side of the specimen to allow measuring the strain
versus load during the test. The horizontal displacement X, Y and the
contraction results were drawn in charts.
Five plain mortar beams were casted and cured for 28 days with dimensions
of (70X70X400) mm and elevated to different temperatures from room
temperature to 800 °C to study the effect of high temperature on the structure of
the mortar and to compare the impact energy.
Also some properties were determined by applying and analysis of many
tests such as, impact (DROP weight) test, abrasion and fire resistance (exposure to
high temperatures). Ultrasonic pulse velocity (UPV) test was applied to find the
effect of high temperatures on the structure of mortar. Finally the scan
electronic microcopy (SEM) was applied for fractographic analysis.
from this research the following conclusions can be drawn:
- Addition of Cu-Ni Ferrite results in an early strength gain of compressive
strength higher than that of normal mixes by approximately 15-20 % at age of 7
days.
- The best ratio of Nano Copper-Nickel Ferrites in chemical composition of
(Cu0.5Ni0.5Fe2O3) addition by weight of ordinary Portland cement was found
to be 0.055%, which is significant in increasing compressive strength by
approximately 10% at 28 days. This different in the results are because of the
hydration acceleration due to the alkali effect.
- The obtained results of Abrasion resistance test specimens contained
Nano Copper-Nickel Ferrites in chemical composition of (Cu0.5Ni0.5Fe2O3)
arrived to increase abrasion resistant by 117 %.
- The results of tested columns that contain 0.055% of Nano Copper-
Nickel Ferrites showed good characteristic behavior in the axial compression
load test reached to 54 % increase compared to those without Nano Copper-
Nickel.
- The flexure results of tested plates and beams that contain Nano Copper-
Nickel Ferrites 0.055% of cement weight showed good characteristic behavior
in the flexure 3 points bending load test which reached to more than 15 %
increase compared to those without Nano material.
Needles shape of the Cu-Ni Ferrites increases tensile and bending strengths by
working as bridges between micro cracks in the matrix of cement mortar.