A blisk is a part in a turbofan with the disc and blades integrated into a single part. The combination of these two components brings weight, power output and design optimisation advantages.
The current trend in turbofan development is to increase utilisation of the blisk and move towards nickel alloys. This will allow the number of stages to be shortened, reduce the size of the disk and reach higher temperatures.
At Makino Europe we have extensive experience in blisk machining – from titanium to nickel alloys, from open to closed blisks, and from big to narrow gaps between the blades.
For titanium blisk machining we have been testing different tool geometries and shapes. One of our most recent developments was to use tapered ball end mills and barrel tools from Schwegler to reduce the number of passes for finishing.
This allowed us to reduce the cutting paths from 63 to 38, a reduction of 40% in the number of passes and almost 50% in cycle time.