Flux-cored wire gas shielded welding is a high quality and efficient welding method

which is widely applied to the pressurebearing welds on the header made of carbon steel

SA-335 P12 and 12 Cr1 Mo VG in boiler industry in the beginning of 21 st century. And the nationalization of these flux-cored wires has been realized. However

for SA-335 P91 material

because the development of flux-cored wire is difficult

the requirements of procedure performance and mechanical property can not be met simultaneously

and R&D cost is high

only a few foreign renowned welding material suppliers research and develop the formula of the flux-cored wire and there are no corresponding welding materials in China now. Therefore

the flux-cored wires for SA-335 P91 made by several famous welding material suppliers are tested

compared and analyzed to study the influence of welding parameters and heat treatment parameters on the properties of SA-335 P91 flux-cored wire joint

thus the influence rules are analyzed and the most reasonable range of welding and heat treatment parameters is obtained. Besides

the macrostructure and microstructure of the welds are observed and analyzed

and further recommendations for improvement are put forward.