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particles reinforced iron aluminide coatings (Fe-Al coatings) were prepared on the surface of 316L stainless steel at only 580uC by a novel approach, namely double glow discharge technique. The chemical composition and morphology of the coatings were characterised by means of glancing angle (1u) X-ray diffractometry, X-ray photoelectron spectroscopy and scanning electron microscopy (SEM) respectively. The hardness, wear and corrosion behaviours of the aluminide coatings were also evaluated. The results indicated that the aluminide coatings exhibited a good wear and corrosion resistance since Al 2 O 3 particles were well distributed in the coatings. The friction coefficient of the composite coatings increased first and then decreased with the increment of Al 2 O 3 particles, meanwhile the corrosion potential and microhardness tended to increase. Finally, the wear mechanisms of the coatings were discussed. IntroductionIron aluminides are candidates for sustainable materials that are very suitable for thermal applications, since they have excellent corrosion properties, high strength and excellent oxidation resistance at elevated temperature. 1 Unfortunately, the high intrinsic brittleness of aluminides limits their usage as a bulk material. Thus, the aluminides are normally used as coatings for their industrial applications. 2 Furthermore, it provides prospective surface properties to strengthen aluminides with dispersed second phase particulates as metal matrix composites (MMCs) coatings. 3,4 Nanocrystalline Al 2 O 3 particulates have unique advantages in comparison to carbides and borides such as high oxidation resistance, chemical inertness and excellent abrasion resistance. 5 Therefore, Al 2 O 3 reinforced aluminides coatings come into prominence as a potential solution to improving the surface properties of stainless steel (SS) under extreme circumstances as anticorrosion and tritium permeation barriers in a flowing Pb-15?7Li environment in nuclear reactors. 6 For decades, a large number of investigations have been focused on the reinforcement of iron aluminides with Al 2 O 3 in different methods. Aluminides (FeAlFe 3 Al) reinforced with 4-9 vol.-% a-Al 2 O 3 dispersions by sintering can gain higher fracture toughness and bending strength. 7 Moreover, FeAl-Al 2 O 3 composites can be prepared via milling of Fe 2 O 3 and Al powders mixture and annealing at 1000uC for 6 h. 8 Hot dip aluminising and electrospark deposition are also effective methods to prepare Fe-Al coatings. 9,10 However, extremely high preparation temperature threatens the properties of substrate materials. In addition, the properties of the coatings are negatively influenced by porous and rough surfaces. 10 Hence, it becomes a key issue to investigate new methods to prepare Fe-Al composite coatings in order to decrease the preparation temperature and improve the surface quality. The advanced double glow discharge technique, which is different from the conventional methods mentioned above, can be adopted to achieve the goal. 11 In this process, ...