Multiple NDE Techniques for the Measurement of Constituent Volume Fractions in Metal Matrix Composites

Abstract Multiple nondestructive evaluation (NDE) techniques are developed for determining the constituent volume fractions of silicon carbide particulate (SiCp) reinforced aluminum (Al) matrix composites. The composite constituents studied include SiCp reinforcement and intermetallic compounds formed during the processing stage. The proposed techniques employ measurements of ultrasonic velocity and eddy current conductivity, together with theoretical models that relate the effective anisotropic properties of the composites to their microstructures. The SiCp volume fraction is calculated first by coupling the measured velocity with the two-phase (SiCp and Al matrix) model prediction. The intermetallics concentration then is calculated using the three-phase (SiCp, intermetallics and Al matrix) model with the measured conductivity. The methods are shown to be reliable in determining the volume fractions of the reinforcement and the intermetallic phase. The techniques may be adopted in a production unit for the quality assessment of the metal matrix particulate composite extrusions.