Why is aluminum difficult to machine.

We know that machining aluminum is not as simple as it seems. There are many grades and for each one there are different machining techniques that can be applied. To begin we will review the different grades of aluminum and from this we will give some recommendations of types of cutting tool to use and the recommended progress.

1100 Aluminum

This grade of aluminum is one of the purest in commercial aluminum. It is easy to machine but difficult to control the chip it produces.

We recommend M / min => 305 (SFM => 1000).

2024 & 6061 Aluminum

These grades are aluminum alloys of high strength and with the possibility of being tempered. They are commonly used in aircraft and automotive components.

We recommend M / min => 183 (SFM => 600).

7050 & 7075 Aluminum

These are the grades of greatest resistance. They are used in the manufacture of maritime ships and aircraft.

This aluminum reacts similar to cutting steels when machined. It is recommended to use high speed techniques when working these materials. In these techniques, light radial cuts should be used.

The material will tend to move if aggressive, deep radial cuts are used at high speeds. This occurs due to high stress levels of the material.

Speeds - You can use higher feed speeds when machining these materials, but they must be combined with a light radial cut and better feed speed control.

A319 -5% Silicon

You can use standard cutting tools

A356-7% Silicon

You can use standard cutting tools.

A380-10.5% Silicon

PCD Tools are recommended for this material. TiB2 or ZrCN coatings should be used if you’re using carbide tools.

A390-17% Silicon

It is only recommended to use PCD. Reduce M/min (SFM) <1000 SFM.