Correlative 3D imaging of internal damage accumulation and 2D surface strain mapping during tensile straining

Understanding defect induced damage accumulation within, and at the surface, of materials and structures is critical to assuring their structural integrity and performance. This work couples synchrotron radiation X-ray computed tomography with high-contrast laser speckle pattern full-field surface strain mapping by digital image correlation to correlate internal defect evolution and surface strain development during tensile straining of the AM titanium aluminide. This comparative analysis reveals strong spatial and temporal correlations relating defect growth to the local strain, providing a new means to observe both the 3D internal and 2D external behaviour of materials under a variety of in-service environments.IMPACT STATEMENTThis paper proposes the synchronous correlative application of X-ray CT and laser speckle DIC for in-situ testing of materials, relating internal structural changes to surface strain evolution.