Magnesium is the lightest commercially available structural metal and exhibits excellent machinability. It has unique characteristics and requires just 55% of the power needed for machining aluminium.
It is safe and recommended to use carbide tooling on magnesium alloys. Best practice for machining magnesium alloys should be followed, keep a look out for further articles on this topic.
Machining magnesium versus aluminium
Tool ranges used during the machining of aluminium can also be used for magnesium. These give satisfactory results. However, due to the free-machining characteristics, relatively low cutting pressures and slightly lower heat capacity of magnesium, best machining practice should take tool material, tool life and tool geometry into consideration.
Cutting speeds and tool stability
The potential for high-speed machining of magnesium alloys is usually only limited by the stability of the component in the clamping device, chip extraction or the rotation speed or accuracy limits of the cutting tool or machine.
The mean specific cutting force (ks1.1) of magnesium is 280 N/mm2 (40.61ksi), much lower than that of aluminium (approx. 640 N/mm2 (92.82 ksi). The result of this means that there is a reduced load on the cutter and tool body allowing higher cutting speeds and feed rates.