Ball screw drive for an actuator group

A ball screw drive for an actuator assembly of a vehicle brake, comprising,

• a rotatably mounted recirculating ball screw spindle, on which a spindle nut open on one side is mounted,
• wherein at least one thread groove is formed on a circumferential surface of the recirculating ball screw spindle, and a corresponding thread groove is formed on an inner surface of the spindle nut, wherein a multiplicity of balls is guided in the thread grooves in such a way that rotation of the recirculating ball screw spindle brings about axial movement of the spindle nut along a rotational axis of the recirculating ball screw spindle,
• wherein the spindle nut is manufactured from rolling bearing steel or from C steel and is hardened at least in a region of the threaded groove;
• and
• wherein the spindle nut has an anti-corrosion coating on an outside surface, the coating being applied to at least an end face and a region of a circumferential wall adjoining the end face,
• wherein the anti-corrosion coating is absent from at least one axial end region of the spindle nut remote from an end face that is configured to engage a brake pad, and wherein the anti-corrosion coating is configured to resist environmental exposure in a brake caliper gap.