Fracture of fibrous metal matrix composites—I. Experimental results

Abstract An experimental investigation of plastic zone geometry, plastic strain magnitudes, and fracture strength was conducted on unidirectionally reinforced boron-aluminum specimens with a center notch. The results indicate that long, discrete plastic shear zones grow from the notch tip in the fiber direction well before fracture. However, no plastic zones were detected along the fracture surface. The plastic zones blunt the notch and cause a significant stress redistribution in the notched specimens. A model is proposed for evaluation of the resulting stress fields. The companion Part II of the paper describes an analysis of the model and its use in fracture strength predictions.

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