Friction Stir Welding Calculator

Calculate FSW parameters for solid-state joining of metals.

Leave blank to auto-calculate

Leave blank to auto-calculate

Typical FSW Parameters by Material

Material RPM Range Traverse (mm/min)
Al 6xxx800-1500100-500
Al 2xxx/7xxx600-120080-400
Copper400-80050-200
Steel200-60050-200
Titanium100-40025-100

Understanding Friction Stir Welding

Key Process Parameters

FSW quality depends on the balance between rotation speed (heat input), traverse rate (weld time), and axial force (material flow). The "hot" vs "cold" weld concept refers to this balance.

Tool Design Principles

  • Shoulder: Generates ~80% of heat, contains material, typically 2.5-3x material thickness
  • Pin: Stirs material, creates mixing, typically 0.9x material thickness for full penetration
  • Shoulder/Pin Ratio: Typically 2.5-3.5:1 for optimal material flow
  • Pin Features: Threads, flats, or flutes improve material flow

Defects and Causes

  • Tunnel Defect: Too cold - increase RPM or decrease traverse
  • Surface Galling: Too hot - decrease RPM or increase traverse
  • Root Defect: Insufficient penetration - increase pin length or force
  • Flash: Excessive heat - reduce force or RPM