Optimization of heat treatment of TRIP steels

  • S. S. Nemecek
  • Z. Novy
  • H. Stankov√°


In transformation induced plasticity (TRIP) steels, proper microstructure is essential. The TRIP effect
provides the material with high plasticity owing to high volume fraction of ductile phases (ferrite and
austenite) in microstructure. In consequence, it provides high hardening through deformation and
transformation. The hardening is caused by transformation of retained austenite to martensite. Suitable
microstructure for TRIP effect can be obtained by either thermomechanical or heat treatment. Present
paper describes development of an intercritical annealing technology, which guarantees fine-grained
microstructure formation consisting of appropriate fractions of ferrite, lower bainite and retained
austenite. Such structure is suitable for further cold forming with TRIP effect hardening.