| 摘要 |
PROBLEM TO BE SOLVED: To obtain a ceramic, metal or carbon hollow rodlike body 3 having improved productivity and high precision. SOLUTION: A material B 2 is built in a material A 1 composed of a ceramic, a metal or carbon to form a combined billet. The combined billet is extruded under pressure to form a combined thin rodlike body 5. Further, the material B 2 of the combined thin rodlike body 5 is removed by combustion, evaporation, sublimation, dissolution, etc., to form the hollow rodlike body 3. |
