K
Key way
A key way is a groove that is machined into the surface of an object. When it is joined with another part that has a section of the same dimensions standing proud, when they are joined they will lock and when rotated the two objects will rotate together.
M
Main cutting edge
The cutting edge that removes material in the direction to which the tool moves.
Martensite
Martensite is a structure that is achieved by rapidly cooling an austenite structure. Martensite is very hard but it is very fragile and as such prone to chipping.
N
NC
NC stands for numerical control. To control a machine using numerical values.
Nitriding
Nitriding refers to a form of surface treatment. The process is carried out to ensure that the surface layer is rich in nitride. In doing so it enables the wear and corrosion resistance properties to be increased.
O
Offset
Refers to the relationship between the position of the side of a tool holder and the cutting edge.
Micro chipping
Refers to problem that means that minute chipping along the cutting edge occurs.
Moulded type
An insert with a chip breaker that has been formed by a mould.
MQL
Minimum Quantity Lubrication.
Normal clearance of main cutting edge
The clearance angle of the cutting edge that enters the workpiece in the direction of tool movement.