Does Aluminum , after machining, continue to dimensionally change over time? A large (1000 mm x 500 mm x 300 mm ) aluminum casting is clamped and machined. Various large diameter hole and drilled. Faces are milled. The casting is stress relieved in the normal manner. Next the milled faces are coated to reduce wear by the air bearing that traverse the face. I have read that the aluminum continues to change both in surface hardness ( Rockwell) and by creep deformation by residual stress. Can one confirm this? I have seen tech papers stating that the dimensions continue to change after 1500 hours. Any input is appreciated.