Abstract: Closure element for a vacuum valve having a valve disk realized for the gas-tight closure of a process volume by means of interaction with a vacuum valve opening of the vacuum valve provided for the process volume, wherein the valve disk comprises a closure side and an oppositely situated rear side which is substantially parallel thereto and a first sealing face which is assigned to the closure side and corresponds to a second sealing face of the vacuum valve opening, in particular with regard to form and size, with cured-on sealing material, wherein the second sealing face runs around the vacuum valve opening, and a cross carrier with a receiving means for a drive component transversely with respect to an extension direction of the cross carrier, wherein the cross carrier is connected to the valve disk on the rear side of the valve disk at at least one connection point. The connection of the cross carrier to the valve disk comprises a friction stir welding connection at the at least one connection point.

Abstract: Provided is a method and tool for butt welding a first material piece of metal to a second material piece of metal at opposed longitudinal edges. The second material piece has a greater material thickness than the first material piece. The first material piece has a higher tensile strength and/or a higher inching temperature and/or a higher yield strength and/or a higher modulus of elasticity than the second material piece. A thickened longitudinal edge is provided at the first material piece. The thickening of the longitudinal edge is at least partly produced by at least simple folding, beading or winding of the first material piece or at least partly by folding the first material piece at its edge. The two material pieces are friction-stir welded at their front along the opposed longitudinal edges.

Abstract: Closure element for a vacuum valve having a valve disk realized for the gas-tight closure of a process volume by means of interaction with a vacuum valve opening of the vacuum valve provided for the process volume, wherein the valve disk comprises a closure side and an oppositely situated rear side which is substantially parallel thereto and a first sealing face which is assigned to the closure side and corresponds to a second sealing face of the vacuum valve opening, in particular with regard to form and size, with cured-on sealing material, wherein the second sealing face runs around the vacuum valve opening, and a cross carrier with a receiving means for a drive component transversely with respect to an extension direction of the cross carrier, wherein the cross carrier is connected to the valve disk on the rear side of the valve disk at at least one connection point. The connection of the cross carrier to the valve disk comprises a friction stir welding connection at the at least one connection point.

Abstract: Provided is a method and tool for butt welding a first material piece of metal to a second material piece of metal at opposed longitudinal edges. The second material piece has a greater material thickness than the first material piece. The first material piece has a higher tensile strength and/or a higher melting temperature and/or a higher yield strength and/or a higher modulus of elasticity than the second material piece. A thickened longitudinal edge is provided at the first material piece. The thickening of the longitudinal edge is at least partly produced by at least simple folding, beading or winding of the first material piece or at least partly by beveling the first material piece at its edge. The two material pieces are friction-stir welded at their front along the opposed longitudinal edges.