Metal matrix composites are currently being considered for use in many applications for their high strength-to-weight and stiffness-to-weight ratios, high wear resistance, and high thermal resistance. The present work focuses on the study of crack propagation in Aluminum monolithic and aluminum metal matrix composites reinforced with continuous stainless steel fibers at 4%, 8%, and 13% volume fractions with five plies, and unidirectional structural configuration. Based on experimental evidence, a micromechanical modeling approach was developed for the prediction of fatigue life and the model was compared with actual fatigue lives for these materials.

This work investigates the hot pressing technique, to produce Al-metal matrix composites (AL-MMC) reinforced with stainless steel fibers. The effect of hot pressing parameters, temperature, holding time, and pressure, was studied from microstructural point of view. Moreover microchemical analysis was carried out for the interdiffusion zone to predict the intermetallic compounds formed through it.Finally, the mechanical properties of the composites and the fracture mechanisms under continuous/incremental monotonic loading were studied. The results revealed that the Al-MMC samples that were prepared at T=640 °C, t=0.25 hr, and P=65 MPa gave an optimum thin continuous and uniform interdiffusion zone and hence the optimum mechanical properties. This interdiffusion zone consists of different distinct phase layers of different intermetallic compounds. Failure analysis proved that damage is initiated early after loading at outer plies and propagates through inner plies until catastrophic failure occurs. The governing damage failure modes are matrix cracking, fiber debonding, and delamination.