Report

Teaser, summary, work performed and final results

Periodic Reporting for period 1 - MISSP (Manufacturing of Integral Stiffened Skin Panels)

Teaser

The MISSP (Manufacturing of Integral Stiffened Skin Panels) project aims at proposing new manufacturing routes for metallic aircraft cargo doors. The main objectives of MISSP project are the following:• To achieve further development, integration and validation of metallic...

Summary

The MISSP (Manufacturing of Integral Stiffened Skin Panels) project aims at proposing new manufacturing routes for metallic aircraft cargo doors. The main objectives of MISSP project are the following:
• To achieve further development, integration and validation of metallic technologies such as innovative light-weight alloys, environmentally friendly and low-cost manufacturing processes, and innovative recycling concepts at the end of the product life cycle.
• To characterize and evaluate the properties of new light high-strength alloys such as Al-Mg-Sc alloys.
• To develop and combine advanced manufacturing processes such as High energy hydroforming, Creep Forming, Laser or Friction Stir Welding.
• To optimize and automate these advanced manufacturing processes through experiments and numerical modelling to increase their efficiency, repeatability and security.
• To design and manufacture metallic structures applying the developed technologies
• To validate the properties of the parts and structures after application of the forming and welding processes.
• To assess the use of these manufacturing processes and advanced alloys for the production of future metallic airframe structures.
• To reduce the overall lead time and production costs for the manufacturing of cargo door structures by limiting the number of parts and assembly operations. WP4 shall evaluate possible cost savings and lead time reduction associated to each of the three design concepts proposed in this project.
It is expected to achieve an overall manufacturing cost reduction between 15 and 40% depending on the level of integration of the chosen concept, the automation of the manufacturing processes and the production rate.

Work performed

For WP1, the exploitable results are:
• Numerical modelling: This activity gave a preliminary NO GO to manufacture the die to form the prototype of WP1;
• Preliminary material investigations:
- Stretch-forming trials: This activity confirmed the results of numerical modelling. Initial forming approach is not relevant. Alternatives are proposed.
- Roll-forming trials: A configuration to form machined sheet with almost zero defect was found. Improvement track and additional trials (surface treatment and painting) are proposed to confirm the robustness of the process.
 
For WP2, the exploitable results are:
• Numerical modelling: This activity gave an approximation of residual stresses and geometrical form of the prototype part after creep-forming. However, errors remain in the model that needs to be solved.
• Preliminary material investigations: Suitable laser and hybrid welding parameters were found for basic and representative configurations on AA5024. This alloy is close to AA5028 that will be used to manufacture the prototypes.
• Tooling development: Supplier for creep-forming tool was selected in line with technical and budget requirements. Final design review was performed before the end of June. Design of welding tool was finished on August, 30th 2018.
For WP3, the exploitable results are:
• Numerical modelling: Simulations of high energy hydroforming (HEHF) and creep age relaxation were performed and are currently calibrated with physical tests.
• Preliminary material investigations:
- Surface stress measurements on HEH formed small scale specimens and creep age relaxation tests were performed.
- Small scale specimens were manufactured with 3 different HEHF production scenarii.
- Machining pattern trials on small scale specimen were performed and highlighted geometrical defects.
• Tooling development: Forming and machining tools were designed and manufactured for small scale specimen. Forming die for full scale specimen was also designed and manufactured.

Final results

Preliminary material investigations and forming trials need to be confirmed on full scale prototype to state on progress beyond the state of the art and potential impacts.

Website & more info

More info: http://missp.eu/index.php/project.