Grain refinement and strengthening of austenitic stainless steels during large strain cold rolling

Austenitic chromium-nickel steels are one of the most important and frequently. The article discusses the issues of cold rolling for grinding grai

Effect of warm rolling on grain refinement and mechanical properties of austenitic stainless steel

The deformation microstructures of a 316L - type austenitic stainless steel subjected to warm plate rolling at temperature of 300°C to different total true strains (ε) of 0.5, 1, 2 or 3 and their effect on the mechanical properties were studie

Microstructure evolution in a 316L stainless steel subjected to multidirectional forging and unidirectional bar rolling

The formation of ultrafine-grained structures was studied in a 316L stainless steel during severe plastic deformation. The steel samples were processed up to a total amount of strain of 4 at ambient temperature using two different methods, i.e., multidirectional forging and unidirectional bar rolling. The large strain developed upon cold working resulted mechanical twinning and partial martensitic transformation. The latter was readily developed during multidirectional forging. After straining to the total amount of strain of 4, the austenite fractions comprised approximately- 0.45 as well as 0.15 in the rolled and forged samples, respectively. Both the multidirectional forging and bar rolling led to extensive grain refinement. The uniform microstructures consisting of austenite and ferrite crystallites with the transverse size of 60 nm and 30 nm were evolved at a total amount of strain of 4 in the rolled and forged samples, respectively. The grain refinement by severe plastic deformation was accompanied by an increase for the microhardness to 5380 and 4970 MPa for the forged and rolled samples, respectivel

Development of ultrafine grained austenitic stainless steels by large strain deformation and annealing

The development of ultrafine grained structures in 316L and 304-type austenitic stainless steels subjected to large strain cold working and subsequent annealing and their effect on mechanical properties were studied. The cold rolling was accompanied by a mechanical twinning and a partial martensitic transformation and resulted in the development of elongated austenite/ferrite grains with the transverse size of about 50 nm at a strain of 4. The grain refinement by large strain cold working resulted in an increase of tensile strength above 2000 MPa in the both steels. Annealing at temperatures above 500°C resulted in ferrite-austenite reversion. However, the transverse grain/subgrain size remained on the level of about 100-150 nm after annealing at temperatures up to 700°

Nanocrystalline structures and tensile properties of stainless steels processed by severe plastic deformation

The development of nanocrystalline structures in austenitic stainless steels during large strain cold rolling and their tensile behavior were studied. The cold rolling to total equivalent strains above 2 was accompanied by the evolution of nanocrystalline structures with the transverse grain size of about 100 nm. The development of deformation twinning and martensitic transformation during cold working promoted the fast kinetics of structural changes. The development of nanocrystalline structures resulted in significant strengthening. More than fourfold increase in the yield strength was achieved. The strengthening of nanocrystalline steels after severe plastic deformation was considered as a concurrent operation of two strengthening mechanisms, which were attributed to grain size and internal stres

Effect of rolling temperature and thickness reduction on the strength of a 316L steel

The relationship between the microstructural changes and the yield strength of a 316L austenitic stainless steel subjected to plate rolling at temperatures of 200 and 300°C with 40, 65, 85 and 95% rolling reductions was studie

Microtexture evolutions in 304L and 316L stainless steels during rolling at 200°C and annealing

The deformation and annealed microtextures were studied in 304L and 316L stainless steels subjected to plate rolling at temperature of 200°C followed by annealing at 700°C for 30-480 min. The evolution of the microstructure and microtexture during rolling at 200°C is associated with the development of deformation twinning and micro-shear bandin

Microstructure and crystallographic texture of silicon iron modified by torsion under quasihydrostatic pressure

The electron backscatter diffraction, X-ray diffraction analysis, electromotive force instantaneous measurement, microhardness and coercive force measurement techniques are used to explore the development of the microstructure, crystallographic texture and physico-mechanical properties of silicon iron (Fe-3% Si) alloy under quasi-hydrostatic pressure in a Bridgman anvil. It is found that the alloy deformation is accompanied by its significant hardenin