Aluminum-

• Based on X-ray tomography (XMT)
• Multi-part FEA model
• Scan to mesh in 10 minutes

based particulate-reinforced metal matrix composites (PMMCs) frequently have a heterogeneous distribution of reinforcement particles whether produced by a powder or liquid processing route. The applicability of X-ray microtomography (XMT) for the characterization of this heterogeneity and its influence on final properties was investigated, for the case of a powder blended and extruded AA2124 matrix with Ni particulate. Simpleware software was used to quantify the embedded Ni particle size distribution and the extent and texture of clusters formed.

X-ray tomography and segmentation in ScanIP
XMT provides a rapid means of generating 3D representations of actual material microstructures in two-phase systems. Segmentation algorithms in ScanIP have been used to segment four components (i.e. Al, TiB2, Fe, Air) based on signal strength.

The example in this computer session considers a subsurface line source (e.g. drip irrigation) of water (first without and then with a solute) in a vertical cross-section. The (x, z) transport domain is 75 x 100 cm2, with the source located 20 cm below the soil surface on the left boundary of the transport domain. Infiltration is initiated with a variable flux boundary condition and is maintained for 1 day, with the duration of the solute pulse being 0.1 days; with 2 cycles per week. An unstructured finite element mesh is generated using the Meshgen-2Dprogram. The example is again divided into two parts: first only water flow is considered, after which solute transport is added. This example will familiarize users with the basic concepts of transport domain design in the graphical environment of HYDRUS, with boundaries and domain discretization, and with the graphical display of results using contour and spectral maps.

Mesh Generation in +ScanFE
In under 5 minutes, an accurate FE mesh has been generated in +ScanFE to determine the reinforcement particle/cluster size distribution and extrusion texture in an MMC material.

FE Analysis
Simulation of the elastoplastic response of the material showed excellent correlation with experimental results. Using the directly meshed microstructure, the elasto-plastic behavior of the complex microstructure was simulated, and excellent agreement was achieved with experimental measurement. This research project was carried out in collaboration with Imperial College London, Department of Materials, London, UK.

Publication
Watson, I.G., Lee, P.D., Dashwood, R.J., Young, P. 2006. Simulation of the Mechanical Properties of an Aluminum Matrix Composite using X-ray Microtomography. Metallurgical and Materials Transactions A, 37A, 551-558.