Interaction between defects, grain boundaries and triple-junctions during grain growth

When annealing a polycrystal, the boundaries between the grains move. Understanding the processes involved in this “grain growth” is a cornerstone of materials science and is pivotal for applications from tensile strength in structural materials to resistivity in electronic materials. The classical picture of grain growth under the curvature driving force has been challenged by recent experimental and theoretical works. It is believed that defects, which are missing in the classical picture and have not been detected experimentally, play an important role in grain growth. With the EBS upgrade and recent development of Dark Field X-ray Microscopy (DFXM), movies of the 3D grain structures and the defect-induced strain field can be mapped faster and with higher resolution. This will pave the way for a comprehensive understanding of the role of strain and defects in grain boundary migration – including a direct test of the recently developed defect-mediated grain boundary migration theory.