Strength design and life assessment of welded structures subjected to high temperature creep

Premature failures of weldments have taken a large percentage among the failure cases of high temperature components. The accurate prediction of the high temperature creep behavior of welded components is hence becoming increasingly important in order to realize an optimized design and management of a plant life. In the present paper, design and life assessment procedure for welded structures at elevated temperature is discussed. A concept of structural creep-rupture strength is proposed to define the weldment creep strength reduction factor. Multiaxial effect is taken into account. A damage mechanics approach is introduced to study the life reduction and ductility reduction due to the presence of a weld in structures at high temperature.