Serial sectioning method in the construction of 3-D microstructures for particle-reinforced MMCs

A serial-sectioning technique is described for obtaining detailed three-dimensional microstructural images from two-dimensional sections of Si-reinforced Al-Si-Mg alloys. Optical micrographs of a series of microstructural sections were generated by the gradual removal of material layers. These micrographs were then enhanced and digitized in a quantitative image analysis system. Three-dimensional microstructure models were then computationally constructed by assembling the digitally acquired two-dimensional micrographs. Serial sectioning was found to be an inexpensive and effective means of accurately depicting heterogeneous microstructures at high resolution. A few relevant observations on material properties also were made during sectioning. Particle cracking was found to occur in larger particles that are located in clustered areas and have their longest dimension aligned with the tensile axis. (C) Elsevier Science Inc., 1998.