Impact Absorbed Energy of Hat Square Column in High Strength Steels

In order to improve the capability of frontal or rear automotive members to absorb impact energy, a basic study was performed to evaluate the effect of strength, micro-structure, and plate thickness on dynamic deformation phenomena using tensile specimens and hat square columns.

Tensile strengths of the materials were selected from 340 to 1180 MPa class steels. Five kinds of micro-structure, Ferrite, Ferrite + Bainite, Ferrite + Martensite, Ferrite + Pearlite, Ferrite + Bainite + γ, and Martensite, were investigated. Tensile tests were carried out under strain rates from 10^-1 to 10³ /sec. and crash tests of hat square columns were conducted under test speeds from 0.1 to 14.0 m/sec.