Aluminium milling

The machinability of aluminium differs primarily depending on the Si-content. Hypo-euthectic is the most common type, with a Si-content below 13%.

The ISO N material group includes not only aluminium, but also magnesium, copper and zinc based alloys.​

Material Classification: N1.1-3

• The dominant wear criteria are built-up edge/smearing on the edges, leading to burr formation and surface finish problems.
• In cast aluminium sand inclusion can sometimes be a problem.
• Good chip formation and evacuation are crucial for avoiding scratch marks on the component surface.
  

Cutters developed primarily for milling of aluminium are:

• CoroMill Century
• CoroMill 790
• CoroMill Plura R216.32, R216.33 and R216.42

Most other CoroMill cutters can be used in aluminium simply by choosing a dedicated insert geometry and grade.

Choose positive insert geometries with sharp edges

• Use uncoated carbide grades (H13A, H10) when Si-content is below approx. 8%
• When the Si-content is above approx. 8%, PCD-inserts (CD10) normally provide better machining cost efficiencies.​

• Unlike most other milling applications, cutting fluid should always be used in aluminium to avoid smearing on the insert edges and to improve surface finish.
• A higher cutting speed generally improves the performance and does not negatively effect tool life.
• A h_ex value of 0.10-0.20 mm is recommended. Values that are too low can lead to burr formation.
  

Warning: Make sure that the maximum rpm for the cutter is not exceeded

• Due to the high table feeds, a machine with ”look-ahead” function should be used to avoid dimensional errors.
• Tool life is always limited by the burr formation or surface finish on the component. Wear on the insert is difficult to use as a tool life criteria.​