Stainless Steel Material Processing

Analysis of Difficulties in Stainless Steel Material Processing

Challenges in Stainless Steel Processing

When drilling, reaming, and boring stainless steel materials such as 1Cr18Ni9Ti and 2Cr13, common issues include:

High Cutting Force and Temperature:
- Stainless steel has high strength and plastic deformation during cutting, resulting in large cutting forces.
- Poor thermal conductivity causes heat concentration near the tool edge, accelerating wear.
Severe Work Hardening:
- Austenitic stainless steels have a strong tendency to work harden, which shortens tool life when cutting through hardened areas.
Tool Sticking:
- The high cutting temperature and tough chips can cause sticking and welding to the tool, affecting surface roughness.
Accelerated Tool Wear:
- High plasticity and cutting temperatures increase tool wear, requiring frequent sharpening and replacement, thus reducing efficiency.

Stainless Steel Material Processing Technology

Drilling

Tool Geometry:
- Increase the top angle to 135°-140° for better durability and narrower chips.
- Sharpen the chisel edge with a bevel angle of 47°-55° and a rake angle of 3°-5°.
- Increase the back angle to 12°-15° to reduce wear and cutting temperature.
Cutting Parameters:
- Cutting speed: 12-15 m/min.
- Feed rate: 0.32-0.50 mm/r.
- Use emulsion as a cooling medium to reduce cutting temperature.

Reaming

Tool Geometry:
- Use carbide reamers with fewer teeth and a rake angle of 8°-12°.
- For high-speed reaming, a rake angle of 0°-5° can be used.
- Back angle: 8°-12°.
- Main deflection angle: 15°-30° for through holes, 45° for non-through holes.
- Blade inclination angle: 10°-20°.
- Back taper for carbide reamers: 0.25-0.5 mm/100 mm, high-speed steel reamers: 0.1-0.25 mm/100 mm.
Cutting Parameters:
- Feed rate: 0.08-0.4 mm/r.
- Cutting speed: 10-20 m/min.
- Rough reaming allowance: 0.2-0.3 mm, fine reaming allowance: 0.1-0.2 mm.
- Use full-loss system oil or molybdenum disulfide as cooling medium.

Boring

Tool Material:
- Use high-strength and high-thermal-conductivity carbide (YW or YG).
- For fine processing, YT14 and YT15 carbide inserts are suitable.
- For batch processing, ceramic tools (Sialon or SiC whisker reinforced ceramics) or CBN (cubic boron nitride) can be used.
Tool Geometry:
- Cemented carbide tools: Rake angle of 10°-30°, back angle of 5°-12°, and main deflection angle of 30°-75°.
- Ceramic tools: Negative rake angle of -5° to -12°, back angle of 5°-12°, and main deflection angle of 30°-75°.
- CBN tools: Rake angle of 0°-10°, back angle of 12°-20°, and main deflection angle of 45°-90°.
Cutting Parameters:
- Use low speed and large feed rate for cutting.
- When using ceramic tools, select cutting amount based on wear durability and tool breakage laws.
- For continuous cutting, the cutting amount can be selected based on tool wear life.
Cutting Fluid:
- Choose fluids with good anti-adhesion and heat dissipation, such as those with high chlorine content or synthetic cutting fluids like H1L-2.

By applying these methods, the processing difficulties of stainless steel can be mitigated, significantly improving tool life and production efficiency while reducing costs and labor intensity.