Titanium alloys were for a time believed to be highly resistant to environmental assisted cracking compared with other engineering materials because of their ability to form a protective oxide film on the surface. The corrosion resistance can still be considered as high but when it was originally defined to ensure functionality of fracture-critical components, unique conditions that promote cracking were discovered.
Today following environmental assisted cracking are discussed for titanium alloys: stress-corrosion cracking (SCC), liquid metal embrittlement and solid metal induced embrittlement (SMIE). Even if failures resulting from these processes are rare, they do occur, partly because of a lack of awareness and partly because of a lack of knowledge of the conditions under which they to occur. The scope of this project is to clarify the effect of copper in contact with titanium alloys, which has been studied in respect to SMIE and SCC. Titanium alloys are frequently used in the aerospace industry where copper contact can be found in, for instance, welding electrodes and fixtures in various manufacturing processes. Initial studies indicate that SMIE in titanium alloys can arise from the presence of copper, but the topic is not fully classified in literature.
Project funding: Volvo Aero Corporation, Graduate School of Space Technology
Kontaktperson: Robert Pedersson
Deltagare: Robert Pedersson, Pia Åkerfeldt and Marta-Lena Antti
Intresenter: GKN Aerospace Engine Systems, Graduate School of Space Technology