ELEMENT ABSORBING ENERGY DURING COLLISION OF VEHICLES WITH DIFFERENT ENERGY ABSORPTION CHARACTERISTICS, AND METHOD OF ITS MANUFACTURING

摘要

FIELD: metallurgy.;SUBSTANCE: invention relates to metallurgy, namely to manufacturing of elements absorbing energy of the vehicles collision. Element is made out of high-strength steel sheet with fracture strength at least 980 MPa, and having the following chemical composition, wt %: C: from 0.14 to 0.30, Si: from 0.01 to 1.6, Mn: from 3.5 to 10, N: 0.0060 or less, Nb: from 0.01 to 0.10, P: 0.06 or less; S: 0.005 or less; Al: from 0.1 to 1.5, iron and inevitable admixture - rest. The sheet has microstructure with ferrite phase from 30 to 70% of volume of entire microstructure, and secondary phase that is different from the ferrite phase, at that average grain size of the ferrite phase is 1.0 mcm or below, secondary phase contains at least residual austenite phase covering at least 10% of volume of entire microstructure, and average interplane distance of the residual austenite phase is 1.5 mcm or below. Index of strain hardening and limit bend radius Rc comply with equation: Rc/t ≤ 1.31×ln(n)+5.21, where t is sheet thickness (mm).;EFFECT: manufactured elements have high characteristics of collision energy absorption during crush action in axial direction.;6 cl, 5 dwg, 5 tbl, 2 ex