• Treated layer : 1 - 3 um
• Oxidized coat layer (Fe304)
• Porous with cutting oil held in pores
• Lowered coefficient of friction
• Prevents fusing
• Unsuitable for non-ferrous metals for internal threads

• Stainless steel
• Titanium alloy
• Mild steel such as SS400
  and S15C

• Treated layer: 30 - 50 um
• Surface hardness: 1000 - 1300HV
• Improve wear resistance
• Infiltration into basic materials

• Cast iron
• Silicon alloy
• Heat-hardened resin

• Treated layer: 1 - 3 um
• Surface hardness: 2000 HV
• Improved wear resistance
• Lowered coefficient of friction
• Prevents fusing
• Improved heat resistance

Prevents fusing

Wear resistance

• Mild steel such as SS400 and S15C
• Hard steel such as S45C
• Alloy tool steels
• Heat treated steels

• Treated layer: 3 - 6 um
• Surface hardness: 3000 HV
• Improved wear resistance
• Lowered coefficient of friction
• Prevents fusing
• Improved heat resistance

Prevents fusing

Wear resistance

• Mild steel such as SS400 and S15C
• Hard steel such as S45C
• Alloy tool steels
• Heat treated steels

• Treated layer: 3 - 5 um
• Surface hardness: 1800 HV
• Prevents fusing
• Improved corrosion resistance
• Improved lubrication

Prevents fusing

Lubrication

For internal thread material easily fused to tap materials

• Copper
• Copper alloy

• Treated layer: 2- 4 um
• Surface hardness: 2800 HV
• Improved heat resistance
• Improved wear resistance

For internal thread materials that wear easily

• High speed cutting (helical cutting)