ASTM F945 brake u-bend titanium specimen

ASTM F945 Titanium Test Specimens

Titanium (AMS 4911, also known as 6Al-4V, and other alloys) test specimens for ASTM F945 stress-corrosion testing. This test measures the stress corrosion cracking of titanium alloy parts caused by aircraft turbine engine cleaning and maintenance materials. Each test specimen measures 0.75" x 3.0" x 0.050". The test specimens have a 0.28" (7mm) hole at each end. For the test itself, the specimen is shaped into a 65° bend; this is called a brake or U-bend specimen. The U-bend specimen is then stressed or restrained with a bolt threaded through the specimen holes and fastened with washers, creating a U shape. Metaspec provides U-bend and preform (not bent) specimens, with or without the stainless steel bolt and unplated washers called for in the test method.


A few test specifications call for F945 specimens to be made from AMS 4916 (8Al-1Mo-1V). This alloy is not commercially available in 0.050" thickness.