Friction Welding Department

What is friction welding?

Friction welding is technology that metals to be bonded are rubbed against each other at high speed and at high pressure to generate friction heat, which softens and bonds the members by metallurgically fusing atoms.

Comparing with conventional arc welding and gas welding*, this is an environmentally friendly bonding method because no heat source other than friction heat is required, no welding rod or flux is required, and no gas or spatter is produced during the bonding.
Currently this method is widely introduced to various industrial fields (automobiles, railroad vehicles, ships, industrial machines, etc.).

*As for bonding of the automotive rear axle housing, the change from arc welding to friction welding enables reduction of CO2 by about 47%.

Features of friction welding

  • Capable of bonding different types of metals.
  • Capable of bonding deformed materials.
  • High mechanical strength of bonded section.
  • No special machining such as grooving is required prior to bonding.
  • High dimensional accuracy of bonded product.
  • Capable of saving materials and reducing man-hour.
  • Friction welding automatically performed has high reliability and reproducibility.
  • Weight of heavy product can be reduced by adopting hollow structure.
Time of lathe machining from round bar: 13 min
Time for friction welding: 0.7 min (friction welding) + 0.5 min (deburring) = 1.2 min

Difference between friction welding and welding

Comparison itemsFriction weldingWelding
(1)Temperature at bonded sectionJust under the melting point of the material that is lower than that of the other materialMelting point
(2) Phase of bonded sectionSolid phase (Liquid phase + solid phase)Liquid phase
(3) Dispersing conditionAtomic behavior by plastic deformationFusion in molten condition
(4) Intermetallic compoundLow possibility of producing compound that may cause lower strength High possibility of producing compound that may cause lower strength
(5) Bonding of different types of materialsCapable of applying to many types of materialsAlmost applying to the same type material
(6) Shape of section to be bondedurface to be allowed to receive pressing force requiredEven complicated shape acceptable
(7) Medium and atmospheric shieldingNot requiredWelding rod and gas such as CO2 required
(8) Ambient temperatureNot affectedAffected
(9) Bonding quality Good reproducibility and high qualityDifficult to completely eliminate pin holes etc.
(10) Bonding strengthEquivalent to or more than base material (entire surfaces to be bonded).Dependent on strength of only groove section
(11) WorkerNo qualification required (automatically performed by the machine)Qualification required