| 摘要 |
PURPOSE:To make the rising part of an output pulse smooth by a method wherein an annular discharge electrode is constituted by a junction of an annular Cu.W electrode and an annular Ni alloy electrode and annular ceramics are provided on both sides of the discharge electrode. CONSTITUTION:A discharge electrode 6 is constituted by a junction of an annular Cu.W electrode 7 made of sintered alloy wherein Cu:W=30:70 and an annular Ni alloy electrode 8 made of Ni alloy wherein Ni:Cu=80:20 and annular ceramics 9 are provided on both sides of the discharge electrode 6 as insulators. If a discharge current is increased in relation to the electrode surface area and the electrode surface temperature when CW oscillation is performed, electrons are emitted from both of the Cu.W electrode 7 and the Ni alloy electrode 8. However, when pulse oscillation is performed, electron emission from the Cu.W electrode 7 is suppressed by its surface oxide and most of electrons are emitted from the Ni alloy electrode 8 which hardly has surface oxide. Therefore, electric power loss which is consumed to break the surface oxide of the CU.W electrode 7 is minimized. |
