Introduction to Aerospace Materials

18

Fracture processes of aerospace materials

18.1 Introduction

Sudden fracture of structural materials was one of the most common causes of accidents in early aircraft. Materials for early aircraft were selected for maximum strength and minimum weight, and their fracture resistance was not an overriding consideration. Furthermore, the capability of materials to resist cracking and sudden failure was not well understood in the design and construction of these early aircraft. Many of the materials used in the earliest aircraft, particularly wood, were prone to sudden fracture which gave the pilot no opportunity to avoid crashing (Figure 18.1). The serious injuries and fatalities during the first decades of powered flight forced engineers to consider ...