Sannakaisa Virtanen

1 INTRODUCTION The efficiency of turbine engines increases by using higher gas temperatures, which results in a striving for materials with higher temperature capabilities. In 2006,[1] the γ′-phase in the Co–Al–W system was (re-) discovered, which allowed the development of Co alloys with better mechanical properties at high temperatures.

Abstract Aerophilic surfaces immersed underwater trap films of air known as plastrons. Plastrons have typically been considered impractical for underwater engineering applications due to their metastable performance. Here, we describe aerophilic titanium alloy (Ti) surfaces with extended plastron lifetimes that are conserved for months underwater.

Abstract Over a decade ago, γ′-strengthened Co-base alloys were introduced as potential replacement for conventional Ni-base Superalloys. Insufficient resistance against high-temperature oxidation restricts the number of possible applications. The present study contributes to the understanding of elementary mechanisms such as material transport during extensive oxide scale formation on γ/γ′ Co-base alloys to explain their inferior oxidation behaviour.