There is provided a method of forming a coupling between a first body (71, 72) and a third body (76), which comprises selecting a first body having a first body layer and a third body having a third body layer; sandwiching a second body layer of a deformable body (74) between said first body layer and said third body layer; forming a first coupling between the third body layer and the second body layer; and forming a second coupling between the first body layer and the second body layer by providing a friction-enhancing fluid medium between the first body layer and the second body layer and without introducing relative sliding there-between pressing the second body layer against the first body layer such as to deform the second body layer into cold pressure welding contact with the first body layer.