Transformation plasticity and kinetic during bainite transformation on a 22MnB5~{s}teel grade
D. S. Schicchi, M. Hunkel,
Volume: 47. Pages: 771--779
DOI: 10.1002/mawe.201600611
Published: 2016
Abstract
The use of press hardening components has widely increased in the
last decades in the automotive industry due to the possibility to
obtain high strength parts with ductile zones for energy absorption.
Conventional and partial press hardening are used depending on the
needed properties of the final components. Quenching, and thus phase
transformation, are performed within the tool under an applied load,
making plausible to assume for the transformation plasticity effect
to play a main role, leading to a minimized spring-back effect. The
influence of stresses, especially larger than austenite yield strength
(high stresses), and pre-strain on the bainite transformation kinetics
are discussed for a 22MnB5 steel grade. Experimental evidence of
the strong nonlinearity of the transformation plasticity of bainite
regarding the applied stresses and differences between tensile and
compression cases are here introduced.