Measurement of Fracture Strains for Advanced High Strength Steels (AHSS) Using Digital Image Correlation

Predicting fracture behavior of Advanced High Strength Steels (AHSS) on both manufacturing and crash simulations is becoming more and more important with the wide use of AHSS in automotive industry. The accurate measurement of fracture strains is a critical input for predicting failure in FEA simulations. It is well known that fracture is a highly localized behavior and fracture strain is gauge or size dependent. In this paper, a full field measurement technique, Digital Image Correlation (DIC), is employed to measure gauge-dependent fracture strains for several Advanced High Strength Steels (AHSS) under tensile test conditions and Limit Dome Height (LDH) tests. Applications of the fracture strains for FEA simulation are discussed.