Abstract: The present invention comprises a method of attaching plastic to a metal substrate and a part made by the method. A hydroformed metal section having top and bottom openings is provided. A plastic component is molded about the metal component and through the bottom opening. The plastic component includes a flange on one side thereof to secure the plastic component with the metal component.

Abstract: A frame member of rectangular cross section with rounded corners is formed by expansion of a tubular blank within a die cavity having an inner portion of corresponding cross section and an outer transition portion which is of smoothly continuously curved cross sectional profile elongated substantially parallel to the larger dimension of the rectangular section. An outer portion of the tubular blank is deformed to correspond with the continuously curved cross sectional profile and is sealed by a resiliently compressible sealing element of corresponding profile through which fluid pressure is applied in order to expand the blank. By matching the profile of the transition portion to the rectangular inner portion, the transition portion can be made shorter and considerable savings of materials and resources can be achieved.