Ultrasonic Casting of Metal Matrix Composites
Researchers at PFL are developing a novel ultrasonic treatment process for manufacturing lightweight, high-strength metal matrix nanocomposites. The strong binding forces at the surface of nanoparticle reinforcements are a severe challenge towards their homogeneous distribution in a metal matrix. This research seeks to utilize high-intensity acoustic waves to deagglomerate and disperse 1D, 2D and 3D nanoparticle clusters in molten metal during casting. The high-intensity ultrasonic vibrations involving cavitation and acoustic streaming mechanisms induce chemical homogeneity, reduced porosity, and efficient melt degassing in a single operation.
The added benefit of grain refinement by ultrasonication further enhances mechanical strength. Structural and mechanical characteristics of the nanocomposites are being probed from macro to nanometric length scales by high-resolution microscopy, electron backscatter diffraction, indentation based mechanical properties, surface profiling, and image analysis techniques. These multiscale processing-structure-property correlations can lead to a major advancement in metal matrix composite manufacturing.
