| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a heating furnace that prevents deformation of a quartz furnace core pipe when inserting a heated material into the quartz furnace core pipe and performing heat treatment, and provide a heat treatment method.SOLUTION: In a heating furnace 1 inserting a heated material (a porous glass base material 5) into a quartz furnace core pipe 2 and performing heat treatment, a carbon-based sleeve 3 is inserted to the inside of a heat zone part 11 of the quartz furnace core pipe 2. The surface of the sleeve 3 is subjected to SiC coating, and the sleeve 3 is arranged inside the heat zone part 11 in a state of being engaged with the upper end of the quartz furnace core pipe 2.</p> |
