What metal material is the nozzle of a car?

1 The fuel injector of an automobile consists of many parts, and the main parts are made of alloy steel. As shown in the figure below:

2 Fuel nozzle: The fuel nozzle is a normally closed valve. When the electromagnetic coil is energized, the suction force is generated, the needle valve is sucked up, the nozzle hole is opened, and the fuel is ejected at a high speed through the annular gap between the shaft pin at the head of the needle valve and the nozzle hole, forming a mist, which is beneficial to full combustion.