To study the extent of residual stress relaxation and characterise the final residual stresses, neutron diffraction measurements and three-dimensional finite element analysis were conducted on a compact tension, C(T) specimen. The specimen was extracted from a dissimilar metal electron beam (EB) welded plate, in the as-welded condition. This was done as a preliminary step to examining crack growth and fracture of a C(T) specimen subjected to applied loads in the presence of residual stresses. The dissimilar metal weld was made from austenitic AISI 316LN stainless steel and a ferritic/martensitic P91 steel, using the EB welding process. The C(T) specimen was extracted from the sample plate using wire-cut electron discharge machining (EDM). The specimen was then measured on the neutron strain diffractometer, E3, at the Helmhotlz Zentrum Berlin (HZB), in Germany. A finite element model was created using the ABAQUS code to simulate the extraction of the specimen from the welded plate, predict the residual stress relaxation and compare with measurements. This paper presents the details of the specimen extraction, the neutron diffraction experiments and the finite element model. The predicted and the measured residual stresses, after specimen extraction are compared with the as-welded residual stresses and the extent of stress relaxation observed.
|Title of host publication||Proceedings of the 7th International Conference on Creep, Fatigue and Creep-Fatigue Interaction (CF-7)|
|Number of pages||6|
|Publication status||Published - 22 Jan 2016|
- Residual stress
- dissimilar metal weld
- electron beam welding
- stress relaxation