Rotor lamination, rotor assembly and motor

The invention provides a rotor lamination, a rotor assembly and a motor. The rotor lamination comprises: a central section having a shaft hole therein; and a plurality of sector sections each extending radially from the central section; a permanent magnet mounting space is formed between every two adjacent fan-shaped sections; a stopping part is arranged at the far end part, deviating from the central section, of each fan-shaped section, and the stopping parts are used for limiting the permanent magnets mounted in the permanent magnet mounting spaces to move in the radial direction; each fan-shaped section is provided with a deformable positioning part at the side part, and each fan-shaped section is correspondingly provided with an avoiding hole at the inner side of the positioning part; and when the permanent magnet is installed in the permanent magnet installation space, the positioning part is pressed by the permanent magnet to face the receding hole in the fan-shaped section to deform, and when the posit