Thin wall tubes with Fe3Al/SS316L graded structure obtained by using laser engineered net shaping technology

In the present paper, designing, technological and material aspects of the Laser Engineered Net Shaping (LENS) manufacturing process of functionally graded materials (FGMs) components based on the Fe-Al intermetallic alloys, have been described in details. The presented results are divided into two parts as follows: in the first part a model and a LENS manufacturing process of the selected FGMs component (the Fe3Al/314L steel tube) have been developed. In the second part, an experimental verification of the model and the process has been carried out. It is shown that, automatically generated code does not allow programming variation of the chemical composition perpendicularly to the wall of the tube. However, applied modification of the code results in a successive direct fabrication of the 316L/Fe3Al FGM tubes. Directly fabricated FGM tubes were characterized by a smooth transition between both components (the 316L steel and the Fe3Al alloy), a high metallurgical quality and a good reproduction of the designed model's shape.