Graphite rod is often used as the heating element of high temperature vacuum furnace. The maximum operating temperature can reach 3000 ℃. It is easy to oxidize at high temperature. Except for vacuum, it can only be used in neutral or reducing atmosphere. Its thermal expansion coefficient is small, its thermal conductivity is large, and its resistance coefficient is (8~13) × 10-6 Ω · m, better processability than SiC and MoSi2 rods, high temperature resistance, good resistance to extreme cold and extreme heat, and lower price.