Servizio Comunitario di Informazione in materia di Ricerca e Sviluppo - CORDIS

Life assessment of dissimilar metal welds for high temperature components

The DISMEW project has developed a life assessment routine for dissimilar welds in steam piping, which functions as a post-processor program for the output of a component finite element analysis. The development is based on a targeted program of experimental and analysis work. Two material dissimilar weld combinations were considered: (2.25)chromium(1)molybdenum to modified (9)chromium(1)molybdenum and modified (9)chromium(1)molybdenum to Esshete 1250. Results from high temperature creep and low cycle fatigue tests on crossweld specimens machined from the welds have been used to rank the weld procedures and calibrate linear damage summation and continuum damage mechanics lifting models.

The life assessment procedures have been implemented as the POST-D post processor. The damage location and life estimates for the P22-P91 component agreed with the benchmark component test results. In the case of the P91-Esshete component, the location of maximum damage was correctly predicted. On the other hand, analysis of the finite element output for models including thermal mismatch produced severe overestimations of the creep damage.

Reported by

CISE Spa
20134 Milano
Italy