TWI Industrial Member Report Summary 687/1999
P J Tubby, E J Olden and G S Booth
Background
With the successful exploitation of high power lasers, laser welding is increasingly being used for structural applications in steel thicknesses up to 20mm and greater. Fatigue performance is a limiting factor where significant cyclic loading is to be resisted, and fatigue design rules have been available for conventional arc welded joints for many years. Gradually fatigue test results for laser welds are now being published. The purpose of this study was to collate and review published fatigue results for laser welded joints in structural steel in order to establish fatigue design guidance. The study was limited to joints in plate of 8mm thickness or greater and steels of yield strength in the range 250-350N/mm 2.
The proposed application of laser welding in ship construction gave significant impetus to the generation of fatigue data, such that the majority of the results included here are taken from a European collaborative programme 'Laser welding in ship construction', which was completed in 1995 and subsequently summarised at an international conference. Data from other sources have also been included.
Objectives
- To collate and review data for laser welded joints in structural steel.
- To propose fatigue design guidance for laser welds.