Drilling Inconel 718 2

[Thewormturner]

I have to drill 1.0 mm dia. holes x 4 mm deep in clean faced Inconel 718.

The drill will be held in a driven tool station on a CNC lathe.

Could anyone advise a suitable drill type with cutting data.

The Wormturner.

 

[BobUXL]

First off, I am assuming that this is solution annealed 718 and not aged.
This size hole is extremely tough but doable. It is best to use coated carbide drills with a 150 degree included angle and a split point. Use a TiAlN coating or better for this material. Speed 35-45 SFPM, .002/.003 ipr. If you cannot get a good quality carbide, M42 will work and this must be coated with TiAlN.

 

[beavers]

We have a similar application, drilling holes 0.5 to 1.5 mm diameter, on screw machines.

We had tried a few suppliers. The best quality and price we found were the drills made by Guhring. They have a large selection of types and sizes.
Check with your local distributor for a Guhring catalog.

When it comes to small diameter holes, it will take also lots of patience, trial and error, until you find the right parameters for your application. The general guidelines from the books don't seem to apply for those small holes.

 

[TVP]

Excellent information from BobUXL and beavers. I wanted to add that a highly sulfurized oil is recommended for drilling operations. I would not bother with high speed steel drills-- just start with TiAlN carbide drills. Guhring is very good.

 

[pohbah]

beavers is about right another company to try for tooling would be OSG who sell good quality tooling, but rather you than me using driven tooling,dependant on the depth of the hole i know you will have your problems, we always bite the bullit and if possible set up a cnc m/c centre to drill holes in exotic materials, i am sure you will find this saves a lot of time/money etc