Chapter 2: Methodology

Abstract

In addition to the global mechanical tests, the microscopic methods for investigating the micromechanism of cleavage fracture include: in situ tensile tests; detailed observations of the fracture surfaces for analyzing the general feature; drawing the map of crack propagation; identifying the critical event for cleavage fracture; locating the cleavage cracking initiation particle; measuring critical values of fracture plastic strain εpc, local cleavage fracture stress σf, and critical value of stress triaxiality Tc for establishing the fracture criteria; electron back-scattered diffraction for measuring the high-angle misorientation boundary; observations of sub-microstructures by TEM; and finite element method calculation and simulation for quantifying all microparameters.