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Iron aluminides possess a unique combination of properties such as attractive corrosion resistance in hot gas and wet chemical environments, a favorable strength to weight ratio, low costs of alloying elements, and they can be processed by conventional methods. For the current study, a promising iron aluminide (Fe-Al-Mo-Ti-B) was employed, which shows the potential to replace costly heat resistant steels or expensive Ni-based alloys for components in large bore two-stroke marine engines. The prechamber, an integral part of the combustion system of dual fuel two-stroke marine engines, which must withstand harsh conditions, was selected as the component. Prototypes made of the novel iron aluminide were manufactured via investment casting and hot isostatic pressing using powder of the intermetallic alloy. The high temperature oxidation behavior, the wet corrosion resistance in acid media, and the mechanical properties up to 700 °C were evaluated. A prototype of the prechamber was tested on a large bore two-stroke dual fuel test engine and post analysis of the tested component was performed. The results show that the employed iron aluminide alloy could be an economic alternative to the currently used Ni-based alloy.

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Die Vorteile von Festkörperlasern für den Schiffbau und für ähnliche Branchen, die durch die Herstellung von Großstrukturen geprägt sind, werden schon seit längerem untersucht. Wesentliche Grundlagen für den Einsatz solcher Strahlquellen auf Werften wurden in Rostock erarbeitet. Von dort ging auch der Impuls für den weltweit ersten Einsatz von Festkörperlasern in der Fertigung einer Werft aus: Seit November 2006 wird ein Hochleistungsfaserlaser mit einer Leistung von 6 kW auf der Aker Werft in Turku, Finnland, zum Verschweißen von Blechen zu Paneelen mit dem Laser‐MSG‐Hybridschweißen eingesetzt.

Tribaloy TM alloys are well-known as wear-resistant alloys, however, their oxidation kinetics and mechanisms are not well studied, especially their long-term oxidation behavior. In this work, the long-term isothermal oxidation behavior of Tribaloy TM T400 and T800 in synthetic air at 900°C for up to 1000 h was investigated. The mass gains of the samples were continuously recorded during the experiments with a thermobalance. Post mortem inspection of the samples was performed and the oxidation mechanism was analyzed. The results show that T800 has a better oxidation resistance than T400. The parabolic rate constant k p of T800 is 4.9•10 −14 g 2 •cm −4 •s −1 , which is approximately one order of magnitude lower than 4.8•10 −13 g 2 •cm −4 •s −1 for T400. The penetration depth of the oxides in T800 is less than half of that in T400 and steady state oxidation is attained after approximately 200 h, compared to 350 h for T400. The better oxidation resistance of T800 correlates with its higher Cr content whereby protective Cr 2 O 3 scales form more readily.