Microstructures and Oxidation Resistance of Fe₃Al Overlay by Manual Arc Surfacing

Using Fe₃Al electrodes by manual are surfacing, the Fe₃Al alloy was successfully deposited on a stainless steel surface.The overlaying processes,microstructures and oxidation resistance properties have been investigated and the results show that because of the innate brittleness of Fe₃Al, the Fe₃Al overlay with no appropriate treatment tended to crack. After 500℃ preheating the matrix and 700℃postweld heat treatment, crack-free Fe₃Al overlay can be obtained.The loss of Al element during the welding is relatively la rge, but it didnt impair the oxidation resistance of the Fe₃Al overlay. After oxidized at 800℃ for 70 h in static air, the Fe₃Al overlay was very slightly oxidized, but the oxidation of the stainless Steel matrix was severe.