Tool and Coating Selector
Once the workpiece material and the operation are selected, a flute count, coating and geometry suggestion is given. On mismatches such as AlTiN in aluminium or a diamond coating in steel, the warning engine steps in.
1. Workpiece material
Example: 42CrMo4, 1.7225, 4140
2. Operation
Recommendation
- Flute count (Z)
- 4
- Cutting speed Vc
- 80–150 m/min
- Coating
- TiAlNAlTiN
- Geometry
- Roughing (wavy profile) or a standard 4-flute tool, medium helix
Frequently asked questions
Why are coated end mills not used in aluminium?
Short answer: a TiAlN/AlTiN coating rounds the cutting edge and aluminium sticks to that rounded edge. In aluminium a polished uncoated or DLC-coated tool with 2–3 flutes and a high helix lasts three to five times longer.
Can a diamond coating be used on steel?
No. The issue is not hardness but chemical diffusion: at high temperature carbon atoms diffuse into the iron, the diamond graphitises and disappears within minutes. Diamond and PCD are for non-ferrous materials, graphite and composites only.
How many flutes suit slotting?
Short answer: 2–3 flutes. In a full slot (ae = D) the volume of the chip gullet governs; four or more flutes pack the chips and break the tool. Where higher productivity is needed the strategy moves to trochoidal milling, and a multi-flute tool can be used at ae ≤ 0.1×D.
What is the difference between TiAlN and AlTiN?
The order in the name shows the dominant element by weight: TiAlN is titanium dominant, AlTiN aluminium dominant. As the aluminium share rises, oxidation temperature and hardness increase. In practice TiAlN suits wet, medium-speed steel work, while AlTiN suits dry/MQL and high-speed work.