Which part is the wheel hub?

[Noah]

Automobile wheel hubs are mounted on the axles. Here are the relevant introductions: 1. Steel wheel hubs: The biggest advantage of steel wheel hubs is their simple manufacturing process, mostly using casting technology, with relatively low cost and strong resistance to metal fatigue. In summary, they are both cheap and sturdy. The disadvantages are also quite obvious, such as their relatively unattractive appearance, heavier weight, greater inertial resistance, average heat dissipation, and they are very prone to rust. 2. Alloy wheel hubs: Alloy wheel hubs are lighter in weight, have relatively smaller inertial resistance, and higher manufacturing precision. When rotating at high speeds, alloy wheel hubs have less deformation, which helps the car improve its ability to drive straight and can reduce fuel consumption. The heat dissipation of alloy wheel hubs is about three times that of steel wheel hubs, which plays a certain role in improving the car's braking ability. The materials used for alloy wheel hubs are mostly chromium, titanium, etc., and the manufacturing cost is higher.