Two technologies, rotary friction welding and magnetic pulse welding/forming, have been developed to produce joints in various metal–metal and metal–non-metal combinations. For the rotary friction welding process, the techniques have been successfully developed to allow high-quality reliable joints for both titanium–stainless steel and titanium–aluminium combinations. The titanium–stainless steel configuration has reached a high level of maturity such that since the final qualification was achieved, about 200 flight units have been manufactured and sold in the last 11 years, with a steady demand over time. This includes ten configurations and two different families concerning length, wall thickness and outer diameter. For the titanium–aluminium transition joint, development and qualification activities were successfully performed in three different geometries: 14″\documentclass[12pt]{minimal}
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