Study On Fusion Welding Procedure Of Fe₃Al/A304 And Properties Of The Jionts

A wide attention on Fe₃Al intermetallic compound were drawn for its special performance such as resisting were, corrode, oxidation and sulfuration. The weldability is bad and it is difficult to extend its application. In this paper the weldability tests have been performed on thin sheets of Fe₃Al intermetallics and 304 Stainless Steel by using EBW Welding and TIG Welding respectively. The microstructure and mechanical properties of the Fe₃Al/A304 joints were studied.Experiments were conducted under the conditions of variant welding parameters by EB Welding. The results are as follows: The vacuum needed for EB welding process eliminated hydrogen-induced cracking and provided better weldment. The weldment did not exhibit any tendency to crack and fold or oxide surface.It was found that fusion zone and heat affect zone(HAZ)were narrow.The weldments have good mechanical properties. The tensile strength of the Fe3Al/A304 joint is as high as 325 Mpa. The microfracture morphology is mixed fracture mostly of norm one, and with obviously tenacity hole and lacerated edge on Fe₃Al side.The weldability tests have been performed on Fe₃Al Intermetallics and 304 Stainless Steel with filler materials of 9Cr-1Mo based alloy,347austenitic stainless steel and Inconel 82 nickel-based alloy respectively by TIG welding, the joints have also been studied. The results are as follows: The weldability of iron-aluminides alloys on TIG welding has close relation with filler materials and welding parameter. Crack forms on welding zone and heating affected zone of Fe₃Al alloy with filler materials of 347austenitic stainless steel and Inconel 82 nickel-based alloy, and .fuzion zone can be found obviously when welded with filler materials of Ni based alloy at the side of Fe₃Al base materials. The molten metal of the pool coagulates along the base material of Fe₃Al alloy with filler materials of 9Cr-1Mo based alloy and the microstructure phase of the joint is homogeneous. The tensile strength of the Fe3Al/A304 joint is as high as 259 Mpa. The Fe₃Al/A304 joint is lacerated on welding zone near Fe₃Al side, The macrofracture morphology is not smooth and the microfracture morphology is mixed kinds of fracture and maybe related to the lacerated edge on Fe₃Al side.