This work package aims to identify the static and cyclic mechanical behaviour of the sound material. For the mechanical behaviour under static loading, the relevant material properties (hardening laws and anisotropy) will be identified for minimum and maximum thicknesses on samples imposing either a homogeneous stress state (tension, compression, shear) or a heterogeneous stress state (combination of different modes). For the mechanical behaviour under cyclic loading, fatigue tests will be performed to generate different SN-curves for different material combinations, to identify a fatigue damage model. For both the static and cyclic tests, fractographic analysis of cracked samples will be performed. In the as received plates, the presence of residual stresses (through the thickness) induced during the rolling process will be evaluated.

Objectives

  • Identification of the hardening behaviour and damage evolution of HSS up to fracture using combined numerical-experimental techniques.
  • Assessment of the relevance of through-thickness anisotropy and inhomogeneities for designing bolted connections with respect to fatigue.
  • Determination of the fatigue resistance of the base materials prior to finishing.
  • Evaluation of residual stresses in the different base materials in different surface conditions.
  • Characterization of the fracture behaviour of the base material under fatigue loading.
  • For each of the above topics, to determine the most suitable experimental setup to arrive at reproducable results with sufficient accuracy.