Microstructure of Ti-6Al-4V specimens produced by shaped metal deposition

Abstract Shaped metal deposition is an innovative technology, which creates near-net shaped components by weld deposition and saves time and material due to the absence of further machining. For Ti alloys this is a big advantage, since these alloys are difficult to shape and also very expensive. Ti alloys are very sensitive to the thermal history and shaped metal deposition introduces for each welding step an additional temperature gradient leading to different microstructures in different regions. Regions which were in the single β phase field during the last welding show a fine needle like microstructure, while regions within the α + β phase show coarser lamellae forming a Widmanstätten structure.

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