There is continuing interest in the use of type ‘300H’ austenitic stainless steel weld metals for a variety of high temperature applications including power generating plant, petrochemical and refinery plant, and other engineering equipment with operating temperatures up to about 800^OC. In some cases simple hot tensile strength is the main design requirement, whereas in others, very long term metallurgical stability and creep performance is essential.

A variety of ‘300H’ type weld metals with different composition balances are available, stabilised or unstabilised and with or without molybdenum. Welding process, flux type and residuals may also have a significant influence on elevated temperature properties.

Some new hot tensile and stress-rupture data from a range of candidate weld metals are presented and reviewed in the light of existing published experience. In particular, hot tensile properties, creep-rupture ductility and rupture stress of weld metal deposited by two flux cored wires tested were found to be comparable with published values for bismuth-free consumables.

Recommendations as to the optimum choice of weld metal for specific engineering requirements are suggested.