Cleavage Fracture Micromechanisms of High Strength Steel and its Heat-Affected Zones

The use of materials in increasingly severe service conditions raises concerns about structural safety with respect to cleavage fracture. There are three main material-related challenges that structures face under harsh environments: 1) the trade-off between strength and toughness; 2) the ductile-to-brittle transition behaviour of BCC high...

A method for determining the constitutive model of the heat-affected zone using digital image correlation

The heat-affected zone (HAZ) is an unmelted region of a welded joint that has changed in material properties because of high temperatures during the welding process. HAZ has a lower strength than the base (parent) material (BM) and the weld metal (WM). The lower material strength is more significant if BM is made of high strength steel and...

A quantitative analysis of hydrogen-induced cracking

Internal hydrogen embrittlement, stress corrosion cracking and external hydrogen embrittlement of high strength steel are analysed. They are found to have lattice decohesion as a common source.