Method of determining an index of quality of a weld in a formed object through mechanical contact testing

A method of evaluating a weld in a formed object having an exterior surface, the method comprising:

• a. performing, on the exterior surface of the formed object, a contact mechanics test of a first region that includes the weld and storing one or more corresponding weld surface mechanical property measurements;
• b. performing, on the exterior surface of the formed object, a contact mechanics test of a second region that excludes the weld and storing one or more corresponding base material surface mechanical property measurements;
• c. determining a difference in the weld surface mechanical property measurements and the base material surface mechanical property measurements based on the contact mechanics test in step a and the contact mechanics test in step b;
• d. performing one or more weld width measurements on the exterior surface of the formed object to determine one or more weld widths;
• e. providing one or more wall thickness measurements of the formed object in the first region and the second region to determine one or more wall thicknesses;
• and
• f. evaluating the weld based on the determined difference in the weld surface mechanical property measurements and the base material surface mechanical property measurements in relation to the determined one or more weld widths and the one or more wall thicknesses of the formed object to provide an index of weld quality.