Purpose: of this paper is the effect of the soft annealing of initial microstructure of the 6Mn16 steel on the kinetics of the austenite formation during next intercritical annealing. Design/methodology/approach: Analytical TEM point analysis with EDAX system attached to Philips CM20 was used to evaluate the concentration of Mn, Ni and Cr in the microstructure constituents of the multiphase ste...

This paper reports on the precipitation behaviour and microstructural evolution in ~20% cold rolled NbMoV and V single microalloyed low carbon steels during intercritical annealing. The microstructure and precipitation behaviour were studied by optical and scanning/transmission electron microscopy and microanalysis, X-ray diffraction technique and Vickers hardness testing. After intercritical a...

this paper provides an overview on obtaining low-carbon ultra-fine grained dual-phase steels through rapid intercritical annealing of cold-rolled sheet as improved materials for automotive applications. a laboratory processing route was designed that involves cold-rolling of a tempered martensite structure followed by a second tempering step to produce a fine grained aggregate of ferrite and ca...

The effect of the initial microstructure and intercritical annealing on mechanical properties and work-hardening response of a high-formability low carbon steel were studied. The work-hardening analysis was based on the modified Crussard–Jaoul method. The ferritic-pearlitic sheets showed low strength and high total elongation with the appearance of the yield point phenomenon. The occurrence of ...

This paper provides an overview on obtaining low-carbon ultra-fine grained dual-phase steels through rapid intercritical annealing of cold-rolled sheet as improved materials for automotive applications. A laboratory processing route was designed that involves cold-rolling of a tempered martensite structure followed by a second tempering step to produce a fine grained aggregate of ferrite and ca...

The effect of microstructural refinement and intercritical annealing on the mechanical properties and work-hardening response of a low carbon St12 steel was studied. It was revealed that intercritical annealing of the ferritic-pearlitic sheet results in the formation of a coarse-grained DP microstructure with discrete martensite islands normally formed in place of pearlitic colonies, which resu...

An ultrafine grained dual phase (UFG DP) steel containing niobium was produced by a new route utilizing simple cold-rolling and subsequent intercritical annealing of ferrite/martensite duplex starting structures. The effects of intercritical holding time on the microstructural evolutions and mechanical properties were studied. The results showed that increasing intercritical holding time enhnac...

an ultrafine grained dual phase (ufg dp) steel containing niobium was produced by a new routeutilizing simple cold-rolling and subsequent intercritical annealing of ferrite/martensite duplex startingstructures. the effects of intercritical holding time on the microstructural evolutions and mechanicalproperties were studied. the results showed that increasing intercritical holding time enhnaced ...

This work deals with the feasibility of obtaining Austempered Ductile Iron with Dual Phase structures (DPADI) through heat treatment, starting from different as-cast microstructures. The mechanical properties on these microstructures were evaluated. DPADI microstructures were obtained by adding different tenors of silicon (2.4% to 4.2%) to the melts and keeping the other alloying elements const...

A microstructure consisting of ultrafine grained (UFG) ferrite with average grain size of ~ 0.7 µm and dispersed nano-sized carbides was produced by cold-rolling and tempering of the martensite starting microstructure in a low carbon steel. Subsequently, fine grained dual phase (DP) steel consisting of equiaxed ferrite grains with average size of ~ 5 µm and martensite islands with average size ...