Thesis Topic

Sustainable machining of Al-Li alloy for aerospace structural parts
Eco-Usinage de pièces de structure aéronautique en alliage Al-Li

Abstract

The aeronautical market is currently driven by a constant increase in air traffic (+6 %/year), and by a high demand for kerosene-efficient aircraft. Nothing seems to impact the aeronautic sector, despite low profitability of the aeronautical sector and the coronavirus period. By 2037-2038, according to Airbus and Boeing forecasts, airlines will be carrying more than 8 billion passengers per year (twice the current number). To achieve this, the air fleet will also have to double, with over 48,000 aircraft in the air by 2038.
To reduce CO2 emissions, it is important to lighten aircraft weight by replacing structural parts (fuselage and wings) made of conventional aluminum alloy (Al 7xxx) with lighter alloys.
Therefore, Constellium has developed a Al-Cu-Li alloy family for aerospace applications (Airware® technology). Airware® is 100 % recyclable, offers highly competitive weight savings on major aircraft parts, and offers the possibility of extending major maintenance intervals by at least 12 years. This product range includes 2050-T84 aluminium alloy for thick products. This alloy offers attractive properties for thicknesses up to around 150 mm and is covered by industry and aircraft manufacturer-specific specifications. Feedback available today on its suitability for downstream processing, including machining, suggests that it behaves similarly to a conventional alloy.
Seco Tools and Constellium recognize the growing importance of these types of alloys in the manufacturing sector. Seco Tools has also identified the need to develop cutting tool solutions adapted to these materials, to comply with trade agreements on sustainable development. On the other hand, Constellium is concerned about the cleanliness of the chips to be recycled (buy/fly ratio >95 %). For this reason, cryogenic assistance is being considered to replace cutting fluids. This would make it easier to recycle chips for foundry applications.

Doctoral advisors

• Gérard POULACHON - Director,
• Frédéric ROSSI.

Partner

• Seco Tools
• Constellium

Project

N/A

Funding

• CIFRE

Start

6th of November 2023

Expected end

5th of November 2026