Effects of microstructure and notches on the mechanical properties of dual-phase steels

Journal Article · Fri Oct 01 04:00:00 EDT 1999 · Materials Characterization

DOI:https://doi.org/10.1016/S1044-5803(99)00044-3· OSTI ID:20006441

Bayram, A; Uguz, A; Ula, M

A low-carbon (0.1%) steel has been subjected to three different heat treatments to obtain dual-phase steels with different microstructures. The steel with the intercriticality annealed microstructure of equiaxed ferrite-martensite exhibited the highest tensile strength, the lowest ductility, and intermediate fracture toughness properties. Step quenching also produced an equiaxed ferrite-martensite structure, but the material had the worst mechanical properties of the three different heat-treatment conditions. In contrast to the other two heat-treatment conditions, step annealing produced a fibrous (fine, needle-like) ferrite-plus-martensite structure. This gave rise to a material of intermediate tensile strength but with the highest ductility, notch strength, and fracture toughness. It is argued that optimum mechanical properties in a dual phase steel can best be achieved by obtaining a microstructure containing fine, fibrous needle-like, martensite.

• Research Organization: Uludag Univ., Goeruekle-Bursa (TR)
• OSTI ID: 20006441
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Journal Issue: 4 Vol. 43; ISSN 1044-5803; ISSN MACHEX
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CORRELATIONS
FERRITE
HEAT TREATMENTS
MARTENSITE
MECHANICAL PROPERTIES
MICROSTRUCTURE
NOTCHES
QUENCHING
STEELS