Shenyang Aircraft cuts fighter jet structure parts’ weight using ESI PAM-STAMP

Sheet Metal Forming
Aerospace & Defense

With both superplastic forming and diffusion bonding simulation using ESI PAM-STAMP, SAC cut by half its average tooling development time of the complicated structure parts and made the fighter lighter.

Yuan Li
General Manager / Shenyang Aircraft Corporation

 

Story

Shenyang Aircraft Corporation (SAC) is China’s largest fighter aircraft manufacturing enterprise. When they developed the Naval Aircraft PLA NAVY, mass reduction was critical in order to provide maximum speed, range and maneuverability.

SAC utilized new high performance materials, such as the TA15 titanium alloy, to help reduce weight. While such materials can be used readily to manufacture components, the real benefit comes from manufacturing the many intricate shapes the design required, without the need for assembly using traditional fastening techniques such as riveting, screwing and adhesive joints, all of which would add weight and increase the number of parts on the aircraft and the complexity of manufacture.

The only solution was to increase the complexity of the formed parts and to assemble them without additional fasteners, through the use of diffusion bonding (DB), a technology using the mingling the atoms of two adjacent parts to achieve permanent bonding.

Shenyang Aircraft Corporation experimented with Superplastic Forming (SPF) as one option to meet challenging geometrical requirements, but with material thickness reaching 50mm, SPF invariably resulted in local striction or thinning. having read about SPF simulation carried out successfully with ESI PAM-STAMP by other leading aircraft manufacturers, SAC then turned to simulation. They chose to rely on the only solution which has demonstrated its capacity to predict, and thereafter avoid, the thinning of the titanium alloy parts: ESI PAM-STAMP. SAC trained no less than 150 engineers on the usage of ESI PAM-STAMP, not only for SPF and DB, but also for other more conventional aero-stamping processes.

With the help of such innovative manufacturing processes, and assisted by ESI PAM-STAMP, SAC managed to achieve an overall mass reduction on the Naval Aircraft, giving this aircraft an agility which would have remained out of reach if conventional manufacturing and assembly techniques had been employed. Incidentally the use of simulation, significantly reduced development costs as large numbers of costly trials were avoided.

One of the many processes simulated to achieve expected results was the double-blanks’ SPF and DB forming process under air pressure. Simulation allowed them to predict and control the thinning of the SPF and DB. In this example, several complex components were replaced by a single part, saving up in weight and avoiding cost- and time-consuming welding operations.

Superplastic Forming / Diffusion Bonding parts

About Shenyang Aircraft Corporation

Shenyang Aircraft Corporation (SAC) has emerged as China's largest fighter aircraft enterprise since its establishment in 1953. SAC has over 15 000 workers and operating personnel, with 2 872 high level and middle level engineers.In addition to jet fighters, SAC's other two primary products are commercial aero-structures and non-aeronautical products like buses and factory storage systems. SAC in the past has done work for British Aerospace, Airbus and Lockheed, and currently has a manufacturing sub-assembly venture with Canadian firm Bombardier Aerospace. China's J-15 carrier-based fighter is the most widely known product made by SAC.

For more information visit Shenyang Aircraft Corporation