Fretting resistant spring design

A nuclear reactor comprising:

• at least a first fuel assembly, the at least first fuel assembly including at least a first fuel rod and at least a first grid, the at least first fuel rod being mounted on the at least first grid;
• the at least first grid including a plurality of straps, at least one of the straps including an elongated strap body having a longitudinal axis and being formed with at least a first open slot and a second open slot, the at least first open slot extending along a first slot axis and the second open slot extending along a second slot axis, the first and second slot axes being substantially parallel and spaced apart and being oriented substantially perpendicular with the longitudinal axis, the at least first and second open slots each extending from a first edge of the strap body and each terminating at an end point, the end point being less than fully the distance from the first edge to a second and opposite edge of the strap body;
• the strap body including at least a first retention plate, the retention plate including a free portion and a connected portion, the free portion terminating on alternate sides at the at least first and second open slots, the connected portion terminating on alternate sides at the first and second slot axes within the strap body;
• a spring being formed in the at least first retention plate by a first closed spring slot and a second closed spring slot, the spring protruding outwardly from the at least first retention plate in a first direction;
• at least a first dimple being formed in the at least first retention plate by a first pair of closed dimple slots, the at least first dimple protruding outwardly from the at least first retention plate in a second direction substantially opposite the first direction;
• the spring including a first spring ligament, a second spring ligament, and a contact plate, the first and second spring ligaments each having a first connection at a first end thereof with the spring contact plate, the first and second spring ligaments each having a second connection with the free portion at a second end thereof, the second connections both being at the same distance from the longitudinal axis;
• the second connections each having a spring connection length along a direction perpendicular to the longitudinal axis;
• the spring contact plate having a spring contact length along a direction perpendicular to the longitudinal axis, the spring contact length being greater than the spring connection lengths of either of the second connections.