Homogenisation approach in analysis of creep behaviour in multipass weld

Abstract

Different zones of welded joints are subjected to different temperature fields during the process of welding. Furthermore, in multi-pass welding, heating and cooling cycles, which occur due to the overlap of the pass beads, lead to the formation of complex microstructures. A method of evaluating the creep response of a multipass weld based on the micromacro mechanics approach is introduced. Multipass weld microstructures consisting of a columnar zone, which can be related to the microstructure of a single pass weld, and a heat affected zones are considered. To model the microstructure of the multipass weld metal the representative volume element (RVE) method is employed. Numerical tests on one-component loading of the RVEs are performed and creep material properties for equivalent weld material reported for welds with different number of passes.

Creep deformation, damage and thermal–mechanical fatigue analysis of high temperature materials and welds

“…This thematic issue of MST presents a selection of peer reviewed articles [1][2][3][4][5][6][7][8][9][10][11] from the conference, focusing on recent advances in creep, fatigue, damage and fracture analysis of high temperature material and welds. The 11 papers presented report both original research and industrial experience.…”

“…The 11 papers presented report both original research and industrial experience. The wide range of topics covered includes: finite element failure and crack growth modelling of parent materials and welds using creep continuum damage models; 1,5 effect of creep deformation on Z-phase formation, 2 creep deformation, rupture and ductility of weld metals; 3 damage behaviour characterisation under creep–fatigue for nickel based superalloys; 4 creep cavitation in stainless steels; 6 creep micro- and macro-damage in notched bars; 7 micro-mechanical creep analysis of multi-pass welds; 8 determination of heat affected zone creep properties using small punch creep testing; 10 and thermal–mechanical fatigue analysis for power plant steels using visco-plasticity models. 9,11 The majority of these topics are relevant to power plant materials (P91, P92, stainless steels and nickel based superalloys) and the structural integrity of components with an emphasis on welds.…”