Location
Brunswick, ME
Start Date
1-1-1992 12:00 AM
Description
The detection of disbonds in riveted lap joints is of increasing interest to the aerospace community. Adhesively bonded and riveted lap joints are used to bond the thin overlapped sheets of aluminum which comprise the outer skin of an aircraft. Through time, the integrity of the bond can become compromised by disbanding, leading to corrosion and stress concentrations at the rivets and subsequent cracking leading to joint failure. A thermal technique for determining bond integrity in these structures has been investigated by Winfree, et al [1]. This technique involves active heating of the aircraft fuselage with a measurement of the temperature on the outer surface of the structure with an infrared imager. By even application of heat to the outer surface of the lap joint, details of the inner structure become thermographically detectable. A disbond will prevent heat from penetrating from the surface layer to the subsurface layers, resulting in an increase in surface temperature over the disbond. Thermographic detection of disbonds excels over other methods by being a noncontacting, quantitative method for inspecting large areas in a short period of time.
Book Title
Review of Progress in Quantitative Nondestructive Evaluation
Volume
11A
Chapter
Chapter 1: Fundamentals of Standard Techniques
Section
Thermal Techniques
Pages
457-464
DOI
10.1007/978-1-4615-3344-3_58
Copyright Owner
Springer-Verlag US
Copyright Date
January 1992
Language
en
File Format
application/pdf
Numerical Solutions for Heat Flow in Adhesive Lap Joints
Brunswick, ME
The detection of disbonds in riveted lap joints is of increasing interest to the aerospace community. Adhesively bonded and riveted lap joints are used to bond the thin overlapped sheets of aluminum which comprise the outer skin of an aircraft. Through time, the integrity of the bond can become compromised by disbanding, leading to corrosion and stress concentrations at the rivets and subsequent cracking leading to joint failure. A thermal technique for determining bond integrity in these structures has been investigated by Winfree, et al [1]. This technique involves active heating of the aircraft fuselage with a measurement of the temperature on the outer surface of the structure with an infrared imager. By even application of heat to the outer surface of the lap joint, details of the inner structure become thermographically detectable. A disbond will prevent heat from penetrating from the surface layer to the subsurface layers, resulting in an increase in surface temperature over the disbond. Thermographic detection of disbonds excels over other methods by being a noncontacting, quantitative method for inspecting large areas in a short period of time.