Paper number 880

MECHANICAL BEHAVIOUR OF PRESSURE-NFILTRATED CERAMIC PARTICLE REINFORCED ALUMINIUM

M. Kouzeli¹ , L. Weber¹ , C. San Marchi¹ and A. Mortensen¹

1Laboratory for Mechanical Metallurgy, Swiss Institute of Technology in Lausanne, CH-1015,Lausanne, Switzerland

Summary

In an effort to clarify the influence of intrinsic matrix and reinforcement properties on the mechanical behaviour of particle reinforced metal matrix composites, we produced and characterised pure aluminium matrix composites reinforced with about 50 vol. pct Al2 O3 and B4 C particles (30µm average diameter). Tensile testing of both materials demonstrate elongations to failure on the order of 2.5%, which is high for composites containing 50 vol. pct ceramic. The two materials differ, on the other hand, with regard to the measured ultimate tensile strengths which are about 120 and 200 MPa for the Al2 O3 /Al and B4 C/Al composites, respectively. Internal damage accumulation was monitored via Young's modulus and density decrease measurements. These data are linked to microstructural observations which indicate two distinct damage mechanisms: (i) particle fracture predominant in the Al2 O3 /Al composite, and (ii) nucleation and growth of voids in the matrix of the B4 C/Al composite.

Keywords

infiltrated composites, particle-reinforced aluminium, tensile behaviour, damage evolution, damage mechanisms.