Investigation Of The Self-Healing Feature Of Continuous Carbon Fiber Reinforced Polypropylene Composites By Joule Effect

Karaman A., Yazıcı M.

ISARC 4. INTERNATIONAL SCIENCES AND INNOVATION CONGRESS, Ankara, Turkey, 19 - 20 February 2022, pp.1

  • Publication Type: Conference Paper / Summary Text
  • City: Ankara
  • Country: Turkey
  • Page Numbers: pp.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.