Ball pin and ball joint

A ball joint comprising:

• a bearing shell,
• a steel ball pin having a joint ball (1) for forming the ball joint with the bearing shell, for use under high static pre-loading,
• a portion of a surface of the ball pin comprising a surface layer hardening (9) for increasing a fatigue strength of the ball pin,
• a portion of a surface of the joint ball, at least in a bearing contact area between the joint ball and the bearing shell has a nitrided layer (6) for providing wear protection and is free from the surface layer hardening,
• another portion of the surface of the joint ball is free from the nitrided layer, and
• the portion of the surface area of the joint ball (1) that is free from any nitrided layer has the surface layer hardening.

A ball joint comprising:

• a bearing shell;
• a steel ball pin having a joint ball for forming the ball joint with the bearing shell, for use under either high static pre-loading or high operating loads;
• at least a portion of a surface of the ball pin having a surface layer hardening (9) for increasing a fatigue strength of the ball pin;
• another portion of the surface of the ball pin, at least in a bearing contact area between the joint ball and the bearing shell is free of the surface layer hardening, and has a nitrided layer (6) for providing wear protection;
• the portion of the ball pin having the surface layer hardening extends over a neck area (3), a seal area (4) and at least partially over a shaft area (2) of the ball pin;
• and
• wherein the ball pin has a nitrided layer on at least a portion of at least one of the shaft area (2) and a threaded area (5) thereof, and the portion of the at least one of the shaft area (2) and the threaded area (5) having the nitrided layer is free from the surface layer hardening.