Description / Abstract:
This SAE Aerospace Recommended Practice describes the aluminum
weldbonding process for fabrication of secondary aircraft
structural assemblies possessing excellent strength, fatigue life,
and environmental durability.
The nature of the weld nugget, produced by resistance
weldbonding, provides microcrack initiators and propagators which
compromise the fatigue life. Additional development work is
required to validate this process for each primary aircraft
structure.
This manufacturing process has been developed and validated for
high strength bare aluminum alloys AMS-4037 and AMS-4045 within the
thickness gages of 0.020 to 0.125 in (0.51 to 3.48 mm). It is
expected to be applicable to other bare aluminum alloys and
tempers. The use of this process is not recommended for clad or
mixed bare-clad alloy systems because of decreased environmental
durability.
The surface preparation system has been validated for use with
80 degrees C (176 degrees F) service temperature modified epoxy
paste adhesive which cures at 120 to 125 degrees C (248 to 257
degrees F). The adhesive contains a radio-opaque substance,
strontium chromate, which permits nondestructure examination for
bondline voids by X-radiography.
Safety-Hazardous Materials:
While the materials, methods, applications, and processes
described referenced in this ARP may involve the use of hazardous
materials, this ARP does not address the hazards which may be
involved in such use. It is the sole responsibility of the user to
ensure familiarity with the safe and proper use of any hazardous
materials to take necessary precautionary measures to ensure the
health and safety of all personnel involved.