980 MPa Grade Low-Alloy Carbide-Free Bainitic Steel Obtained by Dynamic Continuous Cooling Transformation

Strong Bainitic Steels by Continuous Cooling Transformation

Using metallurgical models, three steels were designed to obtain carbide-free bainitic structures in the as-rolled condition. Experimental castings were hot-rolled in a pilot mill and their austenite decomposition kinetics were measured using dilatometry. Tensile and Charpy impact properties were measured and the microstructures were characterised using X-ray diffractometry, optical and scannin...

Nanostructured bainitic steel obtained by powder metallurgy approach: structure, transformation kinetics and mechanical properties

A PM approach is investigated in the context of extremely fine low temperature bainitic steels with a reasonable combination of ultimate tensile strength and uniform elongation. The strategy consists of three steps. First, ball milling is used for mechanical alloying and to create a large density of interfaces prior to sintering. In the second step, spark plasma sintering is used as a rapid con...

Hot Deformation and Processing Window Optimization of a 70MnSiCrMo Carbide-Free Bainitic Steel

The hot deformation behavior of a high carbon carbide-free bainitic steel was studied through isothermal compression tests that were performed on a Gleeble-1500D thermal mechanical simulator at temperatures of 1223-1423 K and strain rates of 0.01-5 s-1. The flow behavior, constitutive equations, dynamic recrystallization (DRX) characteristics, and processing map were respectively analyzed in de...

Exploring Carbide-Free Bainitic Structures for Hot Dip Galvanizing Products

Low–Alloy Duplex, Directly–Quenched Transformation–Induced Plasticity Steel

A duplex microstructure consisting of allotriomorphic ferrite and austenite at ambient temperature, has been produced in a low–alloy steel, by a simple heat treatment which involves intercritical annealing followed by quenching. The tensile properties obtained are good, with a total elongation of some 28% at an ultimate tensile strength approaching 900MPa. The form of the stress versus strain c...