Fracture parameters calibration and validation for the high strength steel based on the mesoscale failure index

Accurately obtaining the material parameters of damage model is very important for ductile fracture simulation steel structures made high strength (HSS). The combination micromechanics with uncoupled phenomenological can be used to obtain locus only from uniaxial engineering stress-strain relationship. A micro failure index generally link under different multiaxial stress status. It relatively difficult describe irregular micro-void evolution using microvoid radius, and also tackle void coalescence mesoscale volume fraction. critical equivalent plastic strain (MCEPS) proposed as at unit cell level calibrate in this paper. HSS calibrated by comparing FE results experimental data homogenized MCEPS maximum surface, respectively. identified further validated against five status, including butterfly shear specimen, tension tensile specimen symmetric round notch, a central hole middle, Sandia challenge specimens 2014. comparisons predictions showed that locus.