Akademik Veri Yönetim Sistemi
ISARC 4. INTERNATIONAL SCIENCES AND INNOVATION CONGRESS, Ankara, Türkiye, 19 - 20 Şubat 2022, ss.1
Materials
are subject to different damages such as aging, abrasion, cracks, or
deformations for different reasons during their daily use. While apparent
damage can be repaired, it is extremely difficult to discover and fix the
damage in inaccessible or difficult-to-control sections in a timely manner. Especially
in engineering materials, such damages cause serious problems. In recent years,
with the development of self-healing materials, it has become possible to
repair the damage in the material in a short time without human intervention.
Self-healing materials are those that have the ability to fully or partially
restore their original properties when damaged during use. The self-healing
mechanisms of materials are different from each other. Basically, self-healing
mechanisms are divided into intrinsic and extrinsic systems. For the
self-healing mechanism to be active, special healing agents are used in
extrinsic systems, while molecular movements and interactions are used in
intrinsic systems with an external energy input such as heat and light.
Reproducibility is possible in the self-healing mechanism in intrinsic systems
and provides advantages in applications. In this study, continuous carbon fiber-reinforced
composite materials with PP matrix were produced, and the self-healing
properties of the parts exposed to deformation as a result of the applied force
were investigated by providing joule heating on the material with the electric
current given to the carbon fibers. To determine the composite material's
self-healing ability, PP/CCF composite specimens in the form of flat plates
were heated to the PP softening temperature and bent into a U shape. The
samples were then cooled to room temperature, and the force was released. The
temporal shape of the samples was fixed with the angle of fixation (θf)
at room temperature, and the fixation ratio (Rf) was calculated. Joule
heating was provided by passing an electric current over the deformed samples. The shape recovery rate (Rr) of the
samples that returned to their original shape with the recovery angle (θr)
was calculated. Thus, the self-healing property of the PP/CCF composite was
determined. As a result, it has
been observed that the CCFs in the PP matrix activate the self-healing feature
of the mechanically damaged structure of the composite with indirectly causing
heating in the part due to the electric current.