Elastic-plastic behavior of shock-loaded Al/Al2O3-fiber composite material.

The dynamic behavior of Aluminium reinforced with Al2O3-fibers has been investigated using planar plate-impact technique in connection with a velocity interferometer VISAR. The measurements are part of a program to classify the protection capability of fiber reinforced materials in light weight armor systems. The material under investigation here consits of an Al2O3-fiber preform (Saffil) embedded in Aluminium matrix material. The measured Hugeniot elastic limit HEL and the spall strength sigmasp of the material have been determined to be 197 MPa smaller than sigmaHEL smaller than 360 MPa and 550 MPa smaller than sigmasp smaller than 640 MPa respectively. The large range of HEL-values seems to be correlated to the impact velocity. Besides the HEL and spall strength Hugeniot data like Us-up and stress-strain-relations will be presented. In addition to the dynamic properties results of the microscopic inspection of sample fragments from recovery experiments will be given. The examination of the sample-fragments by optical and scanning electron microscopy yielded interesting results concerning the response of the reinforcing fibers and the fiber-matrix interface to shock loading.