Extensometer: A device attached to the specimen to measure the exact change in gauge length. This is critical for calculating strain accurately.
For materials without a clear yield point (e.g., aluminum, austenitic stainless steel), the standard mandates the use of – typically ( R_p0.2 ). en iso 6892-1
Thickness between 0.1 mm and 3 mm (Annex B). Wire and Bars: Diameter/thickness less than 4 mm (Annex C). Extensometer: A device attached to the specimen to