Essay On Airplane Failure

STATIC AND FATIGUE FAILURE IN CFRP COMPOSITE LAMINATES UNDER TENSILE LOADING
By
Shriram Gujar

CHAPTER I
INTRODUCTION

1.1 Motivation
In aerospace applications, the demands from the materials are usually greater than the other applications. The most significant requirements are lightweight , high strength, high stiffness, and good fatigue resistance. Composites, are the only existing materials efficiently meeeting these requirements. Some modern airplanes are built with more composites than metal including the new Boeing 787 Dreamliner, Airbus A350XWB.
Aircraft components are exposed to fluctuating stresses and most of these components ultimately fail by fatigue fracture. The main consideration while designing an airplane is

It contains a large volume fraction (up to 70%) of strong fibers that are principle load-bearing constituent. Fibers are generally anisotropic and examples include carbon and aramids.

• Particulate composites:
Particulate composites consist of particles immersed in matrices such as alloys and ceramics. They are usually isotropic because the particles are added randomly. These types of composites contain particulate materials as the dispersed phase. The particles can be either metallic or non-metallic. Particulate composites have advantages such as improved strength, increased operating temperature, oxidation resistance, etc. Examples: Mica flakes in polymers to improve electrical and heat insulating applications,

Lamination is used to combine the best aspects of the constituent layers in order to achieve a more useful material, examples bimetals, clad metals, laminated glass, and laminated fibrous