Manufacturing Methods for Cutting, Machining and Drilling Composites. Volume i. Composites Machining Handbook

摘要

High-quality, low-cost manufacturing methods were established for cutting, machining and drilling of composites. Production nondestructive evaluation (NDE) techniques, capable of insuring structural integrity, were also developed. Materials addressed in this program included graphite/epoxy and hybrids/thereof, boron/epoxy, Kelvar/epoxy and fiberglass/epoxy. Program highlights are described below. Conventional cutting methods were compared to new technology methods such as water-jet, laser and reciprocating cutting. Although the high-speed water-jet and reciprocating cutters worked well with some uncured materials, the slower laser cutter was able to handle all of the materials studied. Several, new low-cost techniques were established for drilling of graphite/epoxy and hybrids thereof. High-speed (21,000 rpm) drilling of graphite/epoxy doubled the life of solid carbide tools. The use of ultrasonic adapters on portable drilling units increased drill life by 100 percent with graphite-boron/epoxy hybrids. Operating parameters were established for routing, trimming, beveling, countersinking and counterboring. In general, diamond-cut carbide router bits were effective for routing and trimming graphite/epoxy and fiberglass/epoxy. A comprehensive review of all available NDE techniques that could be applied to the inspection of cut, drilled and machined composites was made. The most effective technique that could reliably be applied in a low-cost production mode was tracer fluoroscopy.