![]() Typically, these components develop in a Bridgman process where competitive grain selection during directional solidification and a geometric selection process (spiral selector) are combined to select one grain which eventually forms the component 7. Single crystalline components made from nickelbase superalloys are used in the hottest sections of stationary gas turbines or aircraft turbines 6. the Czochralski method 1, the Bridgman method 2, 3 or zone melting 4 or by means of recrystallization as a consequence of abnormal grain growth 5. Single crystals from alloys or semiconductors are normally produced by crystal growth, e.g. This novel, stress induced mechanism opens up completely new perspectives to fabricate single crystalline components and to accurately adjust the orientation according to the load. ![]() Thus, the single crystal forms step by step by merging the originally columnar grain structure. During this second step, the columnar grain structure transforms into a single crystal by rotation of individual grains. The second and new mechanism bases on successive thermo-mechanically induced plastic deformations and texture formation in FCC crystals under compression. The first step is a standard grain selection process due to directional solidification, leading to a pronounced fiber texture. The single crystal develops due to two different mechanisms. Here, we describe for the first time a fully new mechanism to generate single crystals based on thermo-mechanically induced texture formation during additive manufacturing. The single crystal is either produced by growing a seed single crystal or by sophisticated grain selection processes followed by crystal growth. Generally, the evolution of metallic single crystals is based on crystal growth.
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