Surface treatments and Coatings play an important role in the performance of the product. The correct choice of surface finish for the work piece offers the user the following advantages:
• Reduction of power requirement and the possibility of an increase in cutting parameters.
• Avoidance of built up edges and cold chip welding
• Protection from abrasive and adhesive wear and tear
• Provides a heat barrier to the cutting edge
• Possibility of dry machining or the use of minimal coolant
• Improvement in surface finish of the workpiece and higher productivity
Characteristic: Bright surface
The bright finish is primarily supplied for working on non-ferrous metals, Nickel Chrome steels and soft plastics. This surface finish enables optimum chip flow.
Characteristic: Dark blue to black colour surface
Tools are tempered in a steam atmosphere. The resultant oxidization of the surface layer provides increased wear resistance, reduces the possibility of cold chip welding and permits a freer flow of lubrication to the workpiece. Steam temper is not recommended for working on Aluminium.
This surface treatment is the most common used.
Characteristic: Bronze colour surface
This is a stress relieving treatment and is the normal surface treatment for drills in Cobalt.
Characteristic: Blue black colour over flute length
The Molybdenum Sulphide surface finish is an extra coating applied over a previous coating (TiN or TiCN).
It offers superior anti frictional qualities and is particularly recommended for use on materials which are difficult to machine and also where minimal lubrication or dry machining is in operation.
Characteristic: Dark grey to black colour surface
Taps and part finished drills are treated in a Nitrogen atmosphere and then steam tempered . This provides a hard surface and consequently improves wear resistance at the cutting edge. The subsequent flute and point grinding provide optimal chip evacuation. This surface treatment is particularly effective when drilling deep holes and also when drilling and tapping abrasive materials.
Characteristic: Gold / yellow colour over flute length
A coating of Titanium Nitride of between 1.5 - 3 μm is applied to the surface by a PVD process. This gives a surface hardness of approx 2.300 HV on the treated surface and offers the possibility of up to 400% increase in tool life when used on free cutting steels.
This finish also enables increase of up to 60% in cutting speeds with resultant benefits in production capabilities.
Characteristic: Grey violet colour over flute length
The Titanium Carbo-Nitride surface is approx 2 to 3 μm thick and provides a hardness of approx 3000HV. This enables higher cutting speeds to be employed with a resultant considerable increase in productivity.
P7 / P8
Characteristic: Black violet colour over flute length
The Titanium-Aluminium Nitride finish is a multi nano layer surface finish of TiAlN and TiN. It has a thickness of approx 2 to 5 μm and a hardness of approx 3.300HV. It will withstand higher working temperatures (up to 800°C) and therefore is particularly suitable when using minimal cutting fluid or dry machining. Recommended for use on abrasive materials such as Cast Iron or Al-Si alloys. Good all round coating.
Characteristic: Metallic colour on surface
This coating has proven excellent for use on non-ferrous metals. With its higher hardness it is particularly recommended for use on Copper, long chipping Aluminium (without Si ), and on Titanium.