Wetting behavior of al-mg alloys on carbon fiber fabric

In present work, the wetting behavior of carbon fiber and Al-Mg alloys (up to 17 wt.%) from 700°C to 1000°C was investigated by sessile drop method. Below 900°C, the contact angles decreased slightly with increase of temperature regardless of Mg amount. However, the contact angles decreased sharply at elevated temperature (above 900°C). Moreover, below 900°C, the contact angles decreased slightly with holding time, and significant decrease of contact angle with increase of holding time was found above 1000°C. All contact angle-holding time curves at 1000°C demonstrated three kinetic stages. It is observed that the contact angles decreased with Mg amount regardless of wetting temperature. The addition of Mg element will inhabit the nucleation and growth of Al₄C₃ phase, which is unfavorable to the wetting behavior. However, the addition of Mg element will also decrease the surface energy, which demonstrates dominant effect and leads to the decrease of contact angles.