Defect Types

Abstract

This chapter provides an overview of the common types of defects found in various structural materials and joints in aircraft. Materials manufacturing methods (including large-scale production) have been established in the aircraft industry. However, as will be seen in this chapter, manufacturing defects and defects during in-service conditions are very common across all material types. The structural material types include metals, composites, coatings, adhesively bonded and stir-welded joints. This chapter describes the defect types as a baseline for the description of their detection with the methods of Chap. 10.1007/978-3-030-72192-3_5 to 10.1007/978-3-030-72192-3_8. Based on the understanding of the defect types, there is great expectation for a technical breakthrough for the application of structural health monitoring (SHM) damage detection systems, where continuous monitoring and assessment with high throughput and yield will produce the desired structural integrity.

Inhibiting the Oxygen Reduction Reaction Kinetics on Carbon Fiber Epoxy Composites Through Diazonium Surface Modification-Impacts on the Galvanic Corrosion of Coupled Aluminum Alloys

“…The less noble aluminum alloy will become the anode and undergo oxidation at an accelerated rate-socalled galvanic corrosion. [12][13][14][15][16][17][18][19] This type of corrosion can be catastrophic since it can reduce the mechanical strength of the aluminum alloy.…”

“…The general practice to mitigate the galvanic corrosion of aluminum alloys in aircraft structures involves the elimination of direct contact between the two materials by inserting insulation layers [18][19][20] and application of coating systems on the alloy surface. [21][22][23] In principle, the rate of alloy galvanic corrosion can also be reduced by decreasing the rate of the oxygen reduction reaction (ORR) at the exposed carbon fibers of the composite.…”