Carbon Fiber has long been a popular choice for knifemakers who create cutting tools for non-permissive environments. It is strong and has increased cutting ability when ground to a thin edge versus other non-metallic materials like G-10 or Micarta. However, recent testing on the part of Special Circumstances and BFE Labs has shown that carbon fiber can in fact be detected.
If these sort of topics are germane to your interests, I highly suggest you read more about the testing and its implications at BFE Labs: Failure of Carbon Fiber Knives to Pass Metal Detector Screening