Compressive deformation of MWCNT porous preform during infiltration of aluminum or magnesium alloy

Multi-walled carbon nanotube (MWCNT) has sperior high strength, high modulus and high thermal conductivity. The contact angle between MWCNT and molten metal is necessary to estimate the threshold pressure to infiltration. In this study, at first, wettability of the basal plane of graphite by molten aluminum or magnesium was measured using sessile drop method. As the result, the contact angle molten aluminum or magnesium was 127° or 120° respectively. Secondary, wettability of the MWCNT preform by molten aluminum or magnesium was measured. The both molten droplets bounced and rolled on the MWCNT preforms. By means of average values of droplet height, equatorial diameter and interfacial diameter, the contact angle was estimated. As a result, the contact angle between the MWCNT preform and molten aluminum or magnesium was 174° or 165° respectively. By using Cassie's rule of mixture, it was calculated that contact angle between MWCNT and molten aluminum or magnesium was 168° or 150° respectively. Moreover, trial fabrication of MWCNT reinforced aluminum or magnesium alloys composites was carried out by squeeze casting. As the result, these composites were obtained without non-infiltration.