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This article presents a study of corrosion resistance of tin and tin-based composite (Sn + Al 2 O 3 and Sn + SiC) coatings deposited onto aluminium alloy substrates using the low-pressure cold spraying method. The samples were subjected to three different corrosion tests at a room temperature: (i) Kesternich test, (ii) a cyclic salt spray test and (iii) anodic polarisation test. The selected tests allowed extreme environment simulation typical for wide range of urban, industrial and marine service conditions. Evaluation of corrosion was carried out by analysing changes on the coating surface as well as in the microstructure. Additionally, the physicochemical tests were carried out using X-ray diffraction. XRD analysis clearly showed that abhurite Sn 21 O 6 Cl 16 (OH) 14 is the main corrosion product established after the polarisation measurements. Despite extreme corrosive conditions used in experiments all tin coatings showed minor corrosion changes which implies that abhurite serves as a buffer between the metal and the oxidising natural environment.

We report on the magnetic, resistive, and structural studies of perovskite La 1/3 Sr 2/3 CoO 3−δ . By using the relation of synthesis temperature and oxygen partial pressure to oxygen stoichiometry obtained from thermogravimetric analysis, we have synthesized a series of samples with precisely controlled δ = 0.00 − 0.49. These samples show three structural phases at δ = 0.00 − 0.15, ≈ 0.25, ≈ 0.5, and two-phase behavior for other oxygen contents. The stoichiometric material with δ = 0.00 is a cubic ferromagnetic metal with the Curie temperature TC = 274 K. The increase of δ to 0.15 is followed by a linear decrease of TC to ≈ 160 K and a metal-insulator transition near the boundary of the cubic structure range. Further increase of δ results in formation of a tetragonal 2ap × 2ap × 4ap phase for δ ≈ 0.25 and a brownmillerite phase for δ ≈ 0.5. At low temperatures, these are weak ferromagnetic insulators (canted antiferromagnets) with magnetic transitions at Tm ≈ 230 and 120 K, respectively. At higher temperatures, the 2ap × 2ap × 4ap phase is G-type antiferromagnetic between 230 K and ≈360 K. Low temperature magnetic properties of this system for δ < 1/3 can be described in terms of a mixture of Co 3+ ions in the low-spin state and Co 4+ ions in the intermediate-spin state and a possible spin transition of Co 3+ to the intermediate-spin state above TC. For δ > 1/3, there appears to be a combination of Co 2+ and Co 3+ ions, both in the high-spin state with dominating antiferromagnetic interactions.