Reconstruction of surface topographies by scanning electron microscopy for application in fracture research

A New Powerful Tool for Surveying Cleavage Fracture Surfaces

“…Recently an automatic image processing system (ASRS) has been developed which yields a digital elevation model (DEM) of the fracture surface region inspected [16][17][18]. Input data are the two digital stereophotograms (in our case taken with a LEICA S440 scanning electron microscope), each consisting of 1024 x 768 pixels at 256 grey levels.…”

“…Local values of the critical crack tip opening displacement [ 17,181 and the crack tip opening angle [22] have been determined as well as the plastic work which is spent to form a microductile fracture surface [18], based on a model by Stiiwe [23,24]. An example is presented in Fig.…”

Tomography of asymmetric bulk specimens imaged by scanning electron microscopy

“…Two or more images of a specimen in different orientations are required; in the SEM this requirement is achieved through motion of the specimen stage relative to the electron beam. Common points are identified in sequential images by a process called matching, and the three-dimensional coordinate of each point is calculated by triangulation [6]. This results in a point-cloud corresponding to the outer object surface; a mesh is fitted to the point-cloud, which defines the specimen boundaries [7].…”

“…Cornille et al [14] proposed a methodology that corrects SEM image distortions and calibrates the specimen motion without the need for a calibration object. The automatic matching problem was approached by Stampfl et al [6] using cross-correlation of a search area derived from one image to search for the equivalent area in a second image.…”

3D Reconstruction and Visualization of Microstructure Surfaces from 2D Images

“…The sample's macro shape is represented by the 3D mesh, while its micro details are represented by mapping the image texture on the mesh. The method is based on Computer Aided Geometric Design (CAGD) techniques [3], including stereophotogrammetry [4] [5], mesh reconstruction, texture mapping and segmentation. First, 3D points are produced by a stereophotogrammetry process, as shown in Figure 1.…”