A Modified Squeeze Infiltration Process to Synthesize Nickel coated Carbon Fiber Reinforced Al-2014 Composite

摘要

Ni coated carbon fibers were infiltrated with Al-2014 melt using conventional and a modified squeeze cast process. The process modification involved extending the fibers out of the mold and being air cooled during solidification. The process modification was aimed at reducing the damage to the Ni-coating during the infiltration process. The mismatch between the coefficient of thermal expansion of Ni-coating and carbon fiber was found to be the primary reason leading to the damage, which was minimized by adjusting the cooling rates. This process resulted in significant improvement in retention of the Ni-coating compared to the unmodified process. The contents of both nickel and copper in the matrix decreased with increase in the distance from fiber surface suggesting that solidification started in the interfiber region. The Vickers hardness values for the unreinforced portion of the sample, the matrix regions within the fiber tows and at the fiber matrix interface were found to be 55, 72 and 87 respectively.