The spark plug is an essential component of an internal combustion engine. A well-designed plug can maximize fuel economy, reduce emissions, increase engine performance and minimize maintenance.
Most spark plugs have a copper-core center electrode. Copper is an excellent conductor of heat and electricity. However, copper is soft and has a low melting point, so it is always covered with a nickel alloy to protect it. Some plugs also have a platinum or iridium tip on the electrodes. These metals reduce the wear caused by high-voltage sparks. They also help extend the interval between spark plug changes and decrease misfires.