What is the difference between iridium and platinum spark plugs in cars?

[DeLyla]

Automobile spark plugs differ between platinum and iridium in terms of melting point, hardness, and price. Spark plugs are crucial components in the ignition system of gasoline engines. They introduce high voltage into the combustion chamber and generate sparks by jumping the electrode gap, thereby igniting the combustible mixture in the cylinder. Spark plugs mainly consist of a terminal nut, insulator, terminal stud, center electrode, side electrode, and shell. The primary types of spark plugs include: standard spark plugs, projected insulator spark plugs, electrode spark plugs, seat spark plugs, pole spark plugs, and surface gap spark plugs. Working principle of spark plugs: The ground electrode of a spark plug is connected to the metal shell, which is screwed into the engine block via the cylinder head threads. The insulator primarily serves to isolate the metal shell from the central electrode. The terminal nut is the part of the spark plug that contacts the high-voltage coil. After the current passes through the terminal nut and the central electrode, it breaks down the medium between the central electrode and the ground electrode to produce sparks, thus igniting the mixture in the cylinder.