THE HEAT TREATMENT TECHNOLOGIES FOR THIRD GENERATION HIGH-STRENGTH AHSS-STEELS

Abstract

The article provides an overview of modern trends in developing the promising heat treatment technologies for third
generation high-strength AHSS steels (3rd Generation AHSS). It is shown that the formation of a multiphase structure
containing (in various combinations) ferrite, carbide-free bainite, martensite, and an increased volume fraction of metastable
retained austenite, which is prone to deformation martensitic transformation, plays a key role in ensuring the high
mechanical properties at the minimum alloying level. The most promising heat treatment’s directions for third generation
high-strength AHSS-steels are highlighted, namely: a) ART-treatment (Austenite-Reverted-Transformation), used for medium
manganese steels with TRIP-effect (Transformation-Induced Plasticity), b) isothermal quenching for nanostructured
carbidee-free bainite (with the structural components of 30-60 nm in size), c) processing according to the Q&P scheme
(Quenching and Partitioning), d) processing according to the D&P scheme (Deformed and Partitioned).