Layered carbon-fiber product, preform, and processes for producing these

Disclosed is a layered carbon-fiber product obtained by superposing one or more sheets of carbon-fiber fabric each obtained using one or more carbon-fiber bundles each comprising a plurality of paralleled carbon fibers. The layered carbon-fiber product is characterized in that at least some of the surfaces and/or edge faces of the layered carbon-fiber product is constituted of a graphitized part and that the graphitized part gives a Raman spectrum in which the intensity ratio of the D band to the G band (D-band intensity/G-band intensity) is 0.3 or less. Also provided are a preform obtained using the layered carbon-fiber product and processes for producing the layered carbon-fiber product and the preform. The edge faces of the layered carbon-fiber product or preform can be easily processed, and it is possible to highly accurately trim the layered carbon-fiber product or preform while preventing the carbon fibers from fraying at the edge faces. Consequently, the layered carbon-fiber product and the preform can be easily and accurately disposed in a mold and deburring can be omitted, making it possible to attain a cost reduction and a reduction in production time.