Metallurgical Failure Analysis
3568 Caminito El Rincon, #93
San Diego, California, 92130
209 367-1398 - Email: firstname.lastname@example.org
Mark Douglas Bell, PE
Consulting Metallurgical Engineer
|This mainly occurs in some aluminum alloys. The aluminum alloy is rolled into a shape and in so doing the grains are elongated and normally have good mechanical properties. When the material is cut, drilled or machined to expose the grains corrosion will act to separate the layers of grains. This expansion will distort the component, sometimes bread the fasteners and will result in a failure.
Some aircraft aluminum alloys are subject to ex foliation corrosion. Washing and keeping corrosives off the material is the common solution for the aircraft grades.