Loading patent…
AssigneeGM Global Technology Operations LLC
InventorsPaul E. Krajewski, Jon T. Carter
Estimating the term…
The elevated temperature forming of magnesium based alloy workpieces by stretching, drawing, bending (or the like) a surface of the heated workpiece over the forming surface of a forming tool is improved by forming an integral adherent layer of magnesium hydroxide on the tool-contacted surface(s) of the magnesium alloy workpiece. The magnesium hydroxide layer may be formed by treating the surface(s) of the sheet with an aqueous salt solution (e.g., sodium chloride) at a temperature and for a time to form a protective layer of desired thickness (e.g., up to about thirty micrometers). If desired, an additional layer of forming lubricant, such as a film comprising boron nitride, may be applied to the magnesium hydroxide layer.
A method of preparing a magnesium alloy workpiece for a forming process in which the workpiece is heated to a temperature above room temperature and a surface of the workpiece is caused to slide against a surface of a forming tool, the method comprising:
A method of forming a magnesium alloy workpiece into a predetermined three-dimensional shape, the method comprising:
A method of forming a magnesium alloy sheet workpiece into a predetermined three-dimensional shape, the method comprising:
Dependencies are inferred from the claim text.