Study on Increasing Performances of Hybrid Composite Through Pull Out Compression Test Assessement

Abstract

The exhaustive use of light advanced polymer composites into the development of the future high-efficiency long-range commercial aircrafts (primary) structures for increasing strength while decreasing weight for lower fuel consumption and less pollution has attracted great attention in the last decade. In this context, solutions for the integration and joining composites into the aircraft structures metallic sub-assemblies or components, while providing the necessary strength to sustain heavily loaded joints, are urgently required. The paper comes to meet an area of interest for many researchers and large integrators and manufacturers, by presenting several type of metallic join geometrical designs, along with metallic joint part integration solutions into a composite structure directly during production. Performances evaluation of the developed metallic join geometrical designs was performed in static regime by means of �pull-out� compressive tests. The paper focuses on the strength of the hybrid metallic/advanced polymer composites joints. It was concluded that an efficient design of the metallic joint and a proper transition from hybrid to the composite structure can lead to proper integration solutions while assuring safety requirements.

Experimental and Numerical Analysis of the Stress State Produced by a Circular Hole Concentrator

“…The correlation between experimental and numerical results validated capability of the numerical model to reproduce the targeted phenomenon. This allowed further analysis of the stress concentrator, by calculating the gross stress concentration effect, Ktg, (2): (2) where 𝜎 𝑚𝑎𝑥 represents the maximum normal stress at the concentrator peak and 𝜎, the gross normal stress:…”

“…Examples of stress concentrators are keyways, joints, threads, holes etc. The latter is of high importance in structural design, especially the circular hole, as it is inevitable when assembly is required with bolts or rivets [2], but is also, due to its geometric simplicity, used for simulating simple defects or as reference for developing more complex models [3][4][5][6].…”