The objectives of the NGV (Next Generation Vehicle) Project were to demonstrate that stainless steel can be used to reduce weight and costs, and to improve safety and sustainability in structural automotive systems. The deliverables include enabling technologies, virtual technology for design and development, processing and testing. The compilation of the results as well as aspects such as new ...

A systematic study of the influence of plastic deformation and low temperature ageing on the carbon Dislocation Enhanced Finkelshtain Rosin Effect (DEFREIC) in austenitic alloys of Fe-Ni, Fe-Ni-MO, Fe-Mn-A1 and Fe-Cr-Ni systems with different carbon content is reported. The experiments prove that after plastic deformation at room temperature the FR effect is transformed into DEFREIC. nith both ...

A novel variable temperature rolling (VTR) and annealing process was conducted on a metastable austenitic stainless steel. Strain softening occurred during tensile straining in both cold rolled cryogenic rolled-annealed steels, leading to low uniform elongations of only 2-3%. In contrast, thanks the dual-phase heterogeneous lamellar structure achieved via VTR process, ultra-high strength over 1...

In real conditions, austenitic stainless steels solidify in non equilibrium and a two phases microstructure of austenite and ferrite is formed 1 . The aim of this work was to investigate the behaviour of both phases at tensile testing, especially to find out an eventual difference in the relaxation of the deformation energy and the effect of the two phases microstructure in workability. To achi...

Very often, in order to optimized welded constructions, some of their parts are made of heterogeneous steels. For example, microalloyed steels are in use for cars chassis making and high alloyed steels for different constructions making. From that reason, it’s not rare to find welded joints between ferrite microalloyed and austenitic highalloyed steels. As a rule, these joints are welded by usi...

We report the results of magnetic measurements on austenitic stainless steels and duplex stainless steels using a magnetic hysteresis scaling technique. Unlike saturation hysteresis loops, this scaling technique, which uses a set of minor hysteresis loops, can be used in low measurement fields. We show that there is a universal scaling power law between minor-loop parameters, which is independe...

Mature passive films (age > 10 s) were grown in aerated saturated calcium hydroxide solution, at the open circuit, on plain steel and alloys with 9% and 22% Cr, as well as austenitic stainless steels. The materials were commercially produced concrete reinforcing steels. Differences in the polarization of the oxygen reduction reaction were evidenced. Oxygen reduction rates at moderate cathodic p...

The effects of C and N on the work-hardening behaviors were compared in metastable austenitic steels which varied amounts separately added (Fe-18%Cr-8%Ni-(C,N) alloys). Although both suppressed deformation-induced martensitic transformation during tensile deformation due to their austenite-stabilizing effect, they enhanced work hardening steels. Comparison C-added N-added revealed that addition...

The stability of austenite against strain induced martensitic transformation (SIMT) strongly depends on the grain size of the austenite. This is observed in austenitic steels with grain sizes from several pm up to several hundred pm and for much smaller austenitic grains (three orders of magnitude) that are embedded in a non austenitic matrix. fcc Fe-precipitates may be formed in dilute Cu-Fe a...