Titanium as an additional pillar in aircraft manufacturing
AMAG components expands its capacities in hard metal machining
Material selection in the aerospace industry has always been a careful balancing act. Topics such as weight reduction, structural integrity, and durability are of paramount importance. In addition to the indispensable material aluminium, titanium has established itself as another key pillar in aircraft manufacturing since the 1950s.
The lightweight metal Titanium’s (4,5 g/cm3) physical advantages, such as a high strength to weight ratio (it is as strong as steel but about 45% lighter), excellent corrosion resistance, and temperature resistance have led to its increasing use. Two further properties are particularly beneficial for modern aircraft construction: titanium exhibits very low thermal expansion, and its coefficient of thermal expansion is similar to that of modern composites such as CFRP. Moreover, titanium does not corrode when in contact with CFRP due to its electrochemical compatibility, whereas other materials tend to corrode.Especially aircraft developed in recent years with a high proportion of composites, such as the Airbus A350 or the Boeing 787, have been strong drivers for the growing use of titanium. The applications in aircraft manufacturing are diverse. Besides engine components (e.g. fan blades or compressor casings), titanium has secured a firm place in structural components. It is used particularly in areas where extreme loads are concentrated in small spaces for example landing gear struts, wing to fuselage connections, or engine mounts (pylons).Despite its numerous advantages, titanium is considered a challenging material. Its extraction is extremely energy intensive, as is its processing into semi-finished products such as plates or forgings. Machining titanium is demanding due to its poor thermal conductivity. During milling, the heat accumulates at the cutting edge of the tool, leading to significant tool wear. In addition, the material’s high strength requires very robust machine tools to manufacture demanding aerospace components.
Decades of Experience in Hard-Metal Machining
AMAG components can look back on decades of experience in titanium machining. Alongside the production of complex titanium forgings, plates and shaped blanks are also processed. The machine fleet for machining titanium and other hard metals currently comprises 19 machines, 9 of which are specifically designed for titanium and steel. The machining dimensions range from 600 × 600 × 400 mm up to 5,000 × 1,600 × 800 mm. The equipment is largely automated with pallet-changing systems.
The New Arrival
The latest addition to the hard metal machine fleet is a Burkhardt and Weber MCR 900 HVC. It is already the second machine of this type used at the Karlsruhe site for machining hard metal components. The machine is a state of the art 5 axis CNC machining centre controlled by the newest Siemens control system.It offers a machining envelope of 1,800 × 1,250 × 1,600 mm (workpiece interference circle Ø 1,800 mm), a tool magazine with 192 positions, tool lengths up to 900 mm, and tool weights up to 60 kg. The gear spindle with stepless programmable speeds and a maximum torque of 2,000 Nm provides powerful spindle performance with ample reserves. The maximum pallet load is 3,500 kg. This modern machining centre, with its unique capabilities, enables efficient and highly automated manufacturing of modern titanium structural components. To enhance damping and thermal stability, the machine bed, already of massive construction is additionally filled with mineral cast. Generously sized slideways ensure high process stability. Hand scraped elements prevent micro vibrations, and active damping eliminates cutting vibrations at the source in combination with the machine’s substantial total weight of 60,000 kg. These technical refinements ensure high precision, superior surface quality, and reduced tool wear during demanding titanium machining thereby supporting the specially designed coolant system delivering 70 bar pressure and 200 litres per minute. To increase productivity, the machine is equipped with a 4 station pallet changer. This enables optimized setup processes in parallel to machining and is essential for building complex fixturing. The system also includes modern integrated measuring systems for tool monitoring and component inspection. As announced in AluReport 03/2024, this is the next step in expanding the Karlsruhe site into a competence centre for hard metals and forgings. As part of the AMAG components masterplan investment initiative, the company now has state of the art equipment that ensures maximum precision and efficiency.Combined with many years of experience with demanding materials, geometries, and processes as well as rapid industrialisation and strong project management competence, AMAG components is an ideal partner for the production of complex structural parts made from aluminium and titanium.
