Preparation process for coextrusion billets with multiple metallic cylindrical layers

摘要

Coextrusion billets of two or more concentric metallic layers are treated by a hot isostatic pressing process and, then, may be succeeded by heating to an elevated temperature followed by quenching in order to form a diffused bondline between the contiguous touching metal layers, which after extruding and reducing into tubing, is relatively free of bondline defects.