Black low thermal expansion ceramics and component null kodeieraito for the exposure

摘要

PROBLEM TO BE SOLVED: To provide a ceramic having a low thermal expansion property, rigidity, and wear resistance, having low resistance, and having black color. SOLUTION: The ceramic contains (a) at least one kind selected from a group comprising cordierite, spodumene, and eucryptite, (b) carbon, and (c) at least one kind selected from a group which consists of a carbide, a nitride, a boride, and a silicide of a group 4a element, a group 5a element, and a group 6a element and consists of a silicon carbide, a boron carbide, and a silicon nitride. The contents of the components (a), (b), and (c) are 57-99.89 vol.%, 0.01-3.0 vol.%, and 0.1-4.0 vol.% respectively. The ceramic has the porosity of =0.5%, the volume resistivity of =108 Ωcm, and the thermal expansion coefficient at 10-40 deg.C of =1×10-6/ deg.C.