Durability of Metal Aircraft Structures

Originally published in Durability of Metal Aircraft Structures by Atlanta Technology Publications, S. N. Atluri, C. E. Harris, A. Hoggard, N. Miller, and S. G. Sampath (eds.), (1992), pp. 350-361.
Authored by Allan H. Clauer, Jeff L. Dulaney, Richard C. Rice, and John R. Koucky
ABSTRACT
This paper presents an overview of Laser Shock Processing and then discusses how the process can be extended to treat fastener holes on aging aircraft. The process is used to treat localized fatigue-critical areas by developing deep residual compressive stresses to inhibit the initiation and propagation of fatigue cracks. This feature can be applied to fastener holes in aircraft structures to determine whether the fatigue life associated with the failure in these areas can be increased.
INTRODUCTION
Laser Shock Processing (LSP) has become a commercially viable process within the last few years with the design, construction and operation of a prototype laser that is very compatible with a manufacturing environment in size and capability. While still in the development stage, its ability to develop deep, high compressive stresses in the areas treated has been demonstrated on a number of metals and alloys. There have also been demonstrations of large improvements in the fatigue life and fatigue strength in various metals and alloys. In this paper, the laser peening process and representative examples of property improvements in aluminum and steel will be discussed. In addition, the application of the process to treat fastener holes in aging aircraft will be discussed.
To download the entire article- as a pdf: Laser Shock Processing for Treating Fastener Holes in Aging Aircraft