Study on processing of MoS₂ solid lubricant film for anti-corrosion and anti-ablation protection of airborne launcher slide track

The MoS₂-based solid lubricant film PMM with excellent lubricity, good sealing and anti-corrosion abilities is able to efficiently protect the slide track of airborne launcher made of LYXX duralumin alloy or LCX super duralumin alloy against the ablation and corrosion in the humid coastal atmosphere. However, conventional MoS₂-based solid lubricant films require curing at elevated temperatures as high as 200°C, which inevitably leads to damage to the mechanical properties of the Al-based alloys and even causes catastrophic failure of the devices or components owing to the significant loss in the mechanical strengths of the Al-based alloys. Therefore, it is imperative to develop improved curing process which allows the solidification of the MoS₂-based solid lubricant film at relatively low temperatures. The changes of mechanical properties of tensile strength, yield strength, impact strength and elongation of the two different Al-based alloys with temperatures at 25°C, 130°C, 150°C, 160°C, 180°C and 200°C are investigated; the results are given. Through metallographic inspection, we find that the corrosive rate increases with the treatment temperature when it is above 150°C though the microstructures of the alloys have no obvious changes. In order to cure the film at lower temperature, composite accelerative additives containing phenol, ameliorated dicyandiamide, etc., are applied and their polymerization reaction during curing process is characterized by FT-IR and DSC. The conventional properties such as adhesion force, flexibility and impact strength, environmental condition test and tribological properties of PMM bonded solid lubricant film are determined. All these results show that the MoS₂-based solid lubricant film PMM on steel could be cured at 200°C±2°C for 1 h while the film with the FT accelerative additives on Al-based alloys could be cured at 140°C±2°C for 3 h, which ensures that the launcher operates well in both rocket motor simulation test and field test.