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PVD-TiMgGdN coatings have been successfully developed by the authors using an industrial DC-magnetron PVD unit. The coatings reveal excellent corrosion protection capabilities for mild steel substrates for at least 800 h in the neutral salt spray test (NSS). MgGd was added to the TiN matrix by using segmented (Seg.) multi-component targets, consisting of segments of pure Ti and of a Mg- 30 wt.-% Gd alloy. The Seg. targets caused an increased defect density due to droplets forming at the gaps between the segments which leads to an unsatisfactory wear performance. To overcome the low mechanical and wear properties by keeping the coatings excellent corrosion performances stable, a TiMgGd target with a specific Ti:Mg:Gd ratio was manufactured by powder metallurgy (PM) technology processed out of pure metal powders. In the present work, the properties of the corrosion and wear performance of DC-PVD-TiMgGdN coatings, which were synthesized onto corrosive mild steel substrates by using a Seg. target and a PM target of comparable Ti:Mg:Gd ratios together with identical deposition parameters, are compared with each other. The coatings were characterized regarding their microstructural, mechanical, physical and corrosion properties. Furthermore, ball on disk wear tests were conducted by reciprocal dry sling SRV III tests. It is shown that the excellent corrosion performance, could significantly be boosted by using the PM TiMgGd sputter target. Moreover, a remarkable increase in wear resistance of the TiMgGdN coatings can be examined by the use of a PM sputter target. It was found that the chemical properties of the TiMgGdN coatings as well as the nitrogen gas flow have a major influence on the mechanical coating properties and on the resulting microstructure, which directly correlates with the corrosion and wear properties. • Different microstructural properties of PM coating in comparison to Seg. coatings • Hardness values of the PM coatings are increased in comparison to Seg. coatings. • The PM coatings show grain refinement in comparison to the Seg. coatings. • The friction coefficient of PM TiMgGdN coatings is lower in comparison to Seg. coatings. • Substrate protection by DC-MS-TiMgGdN coatings up to 800 h in salt spray test [ABSTRACT FROM AUTHOR]

• Peculiarities of Al alloy temperature-induced localized chemical corrosion are discussed. • Pre-processing procedure of experimental data is developed. • Statistical extreme value analysis is employed for characterization of pit initiation and growth. • The results allow prediction of expected maximum pit sizes after corrosion reaction. Temperature-induced localized chemical corrosion of AA-1050 in anhydrous ethanol is examined experimentally at 105 °C and 110 °C and the generated data is analyzed based on statistical methods. Initiation times are described by a Weibull distribution whereas pit maxima are proven to be drawn from Gumbel parent distribution which is confirmed by modified Anderson-Darling test. Expected values and Gumbel parameters are correlated to reaction times in order to predict maximum pit sizes. Moreover, alcoholate corrosion reaction mechanism is postulated based on published literature and our observations. The statistical methodology can presumably be applied to other fuel-material combinations. [ABSTRACT FROM AUTHOR]