Silver carbon (AgC) or silver graphite (AgGr) contacts are typically produced by a powder metallurgy sintering-repressing process method. They exhibit excellent anti-welding properties in the switch and yet due to this characteristic, it cannot be directly welded, but needs to be decarburized to be combined with the switch terminal. Silver carbon (AgC) or silver graphite (AgGr) contacts produced by the powder metallurgy process has a carbon system distributed in the direction of the parallel contact surface, thereby having excellent anti-welding characteristics, but the inability to withstand arc erosion and high burning rate as disadvantages, thence AgC, AgGr contacts usually work in pairs with silver tungsten (AgW) or silver tungsten carbide (AgWC).