| 摘要 |
A ceramic heater having a substrate and a heat-generating element. The substrate is formed from an electrically insulating ceramic and extends rearward from the forward end of the ceramic heater in the direction of the axis. The heat-generating element has a heat-generating portion formed from an electrically conductive ceramic which contains silicon nitride and an electrically conductive material, disposed in a forward end portion of the substrate, and having a shape resembling the letter U as viewed along the direction of the axis. The heat-generating portion has a fracture toughness of 4.3 Mpa·m 0.5 or more. |
