| 摘要 |
PURPOSE:To obtain an acoustic carbon diaphragm having an equal transfer speed of sound and a wide reproducing compass, by heating porous carbon formed body to an equal temperature, and accumulating thermal cracking carbon of a gaseous phase generated by thermal cracking of hydrocarbon, from the surface part. CONSTITUTION:Nonwoven fabric or woven fabric of a carbon fiber having a high elastic modulus is impregnated with a thermosetting resin, and thereafter, heated and formed to a diaphragm shape, burned in an invert gas atmosphere, and a porous carbon formed body consisting of carbon fiber-resin carbon is obtained. The formed body is used a base material, it is heated to an equal temperature, and to said material, hydrocarbon is led together with carrier gas and thermal cracking carbon of a gaseous phase which has been generated by thermal cracking of hydrocarbon is accumulated from the surface part. In this way, an acoustic carbon diaphragm having an equal transfer speed of a sound and a wide reproducing compass is obtained.
|
