What Materials Are Used in Automotive Spark Plugs?
2 Answers
Automotive spark plug materials are broadly categorized into: nickel alloy spark plugs, platinum spark plugs, and iridium spark plugs. The material of a spark plug typically refers to the electrode material. Currently, platinum and iridium spark plugs are considered superior. Platinum and iridium are precious metals with excellent resistance to high temperatures, high pressure, and corrosion, making them ideal for spark plug manufacturing and significantly extending the spark plug's service life. A spark plug consists of two main components: the insulator and the metal shell. The metal shell is threaded for screwing into the cylinder. Inside the shell is the insulator, through which runs a center electrode. The top of the center electrode has a terminal nut to connect to the high-voltage wire from the distributor. The lower end of the shell is welded with a ground electrode, with a gap of 0.6 to 1.0 millimeters between the center electrode and the ground electrode. When high-voltage electricity passes through this gap to ground, it generates a spark to ignite the air-fuel mixture.
Automotive spark plugs are mainly categorized by material. The standard version commonly uses nickel alloy, which is cost-effective but has average durability, requiring replacement every few tens of thousands of kilometers. The upgraded version features platinum material, with a more wear-resistant center electrode, extending lifespan to around 100,000 kilometers. High-end vehicles often use iridium spark plugs, which have a high melting point and stable ignition, significantly improving performance but at a higher price. There are also hybrid versions like double platinum or iridium-platinum, specifically designed for turbocharged engines. Choosing the right material ensures faster engine response and better fuel efficiency, while the wrong choice may affect cold starts. Therefore, avoid cheap off-brand options and match the specifications in your vehicle's manual.
