The difference between AlTiSiN (Aluminum Titanium Silicon Nitride) and TiSiN (Titanium Silicon Nitride) coatings

• AlTiSiN

  • Elements: Al, Ti, Si, N

  • Aluminum → forms a dense Al₂O₃ protective layer at high temperatures, enhancing oxidation resistance.

  • Silicon → refines the grain structure, improving hardness and wear resistance.

• TiSiN

  • Elements: Ti, Si, N

  • No aluminum → lacks the protective Al₂O₃ film at high temperature.

  • Relies on TiN’s wear resistance + Si grain refinement for hardness and heat resistance.

• AlTiSiN: 3500–3800 HV

• TiSiN: 3200–3400 HV
   AlTiSiN is slightly harder.

• AlTiSiN

  • Oxidation temperature: 1100–1200℃

  • Suitable for dry cutting and high-speed machining.

• TiSiN

  • Oxidation temperature: 800–900℃

  • Weaker at high temperature compared with AlTiSiN.

• Both are lower than traditional TiN.

• AlTiSiN → better for high-speed, high-temperature operations.

• TiSiN → good for medium temperature and high-hardness steels.

• AlTiSiN-coated tools

  • High-speed milling, dry cutting, stainless steel, nickel-based alloys, titanium alloys, other difficult-to-machine materials.

  • Molds: hot-work molds, stamping dies.

• TiSiN-coated tools

  • General steel machining (HRC ≤ 55).

  • Drill bits, end mills, taps, and general-purpose cutting tools.

  • Good balance of hardness and cost for standard applications.

AlTiSiN = with Al → better at high temperature → best for high-speed & difficult materials
TiSiN = without Al → weaker at high temp → good for standard machining