EFFECT OF GRAIN SIZE ON THE DRAWABILITY OF THE NIOBIUM-STABILIZED FERRITIC STAINLESS STEEL ASTM 430

Typical applications of ferritic stainless steels require good formability of a steel that is highly dependent on the processing route. In this study, the effects of heating rate and peak temperature on the texture and formability of a 78% cold-rolled unstabilized 17%Cr (AISI 430) ferritic stainless steel were studied. The cold-rolled sheet pieces were heated in a Gleeble 3800 simulator at the heating rates of 25 °C/s and 500 °C/s up to various peak temperatures below 950 °C for 10 s holding before the final cooling at 35 °C/s to room temperature. Microstructures were characterized and the texture of the annealed samples determined by the electron backscatter diffraction method. The R-value in various directions was determined by tensile straining to 15%. It was established that the high heating rate of 500 °C/s tends to promote the nucleation of grains with the {111}<uvw> orientations during the early state of the recrystallization. The higher heating rate led to a slightly finer grain size and to a marginal improvement in the intensity of the gamma-fibre texture. A coarser grain size would be beneficial for the formability, but the grain growth was suppressed due to low peak temperatures and a short soaking time. Anyhow, the fast annealing resulted in an enhanced R-value in the transverse to rolling direction. The results indicate that even a short annealing cycle is plausible for producing ferritic stainless steels with the formability properties comparable to those of commercial counterparts.

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Influence of Nb content on grain size and mechanical properties of 18wt% Cr ferritic stainless steel

Materials Science and Engineering A ◽

10.1016/j.msea.2016.09.080 ◽

2016 ◽

Vol 677 ◽

pp. 453-464 ◽

Cited By ~ 19

Author(s):

Y. Kang ◽

W.M. Mao ◽

Y.J. Chen ◽

J. Jing ◽

M. Cheng

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Stainless Steel ◽

Ferritic Stainless Steel ◽

Nb Content

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The effect of grain size and initial texture on microstructure, texture, and formability of Nb stabilized ferritic stainless steel manufactured by two-step cold rolling

Journal of Materials Research and Technology ◽

10.1016/j.jmrt.2019.07.024 ◽

2019 ◽

Vol 8 (5) ◽

pp. 4151-4162 ◽

Cited By ~ 8

Author(s):

Daniella Gomes Rodrigues ◽

Cláudio Moreira de Alcântara ◽

Tarcísio Reis de Oliveira ◽

Berenice Mendonça Gonzalez

Keyword(s):

Grain Size ◽

Stainless Steel ◽

Cold Rolling ◽

Ferritic Stainless Steel ◽

Initial Texture

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Grain size distribution after similar and dissimilar gas tungsten arc welding of a ferritic stainless steel

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb120521001r ◽

2015 ◽

Vol 51 (1) ◽

pp. 61-66

Author(s):

E. Ranjbarnodeh ◽

S. Serajzadeh ◽

A.H. Kokabi ◽

A. Fischer

Keyword(s):

Grain Size ◽

Stainless Steel ◽

Size Distribution ◽

Grain Growth ◽

Grain Size Distribution ◽

Ferritic Stainless Steel ◽

Arc Welding ◽

Gas Tungsten Arc Welding ◽

Gas Tungsten Arc ◽

Gas Tungsten

In this study, gas tungsten arc welding of ferritic stainless steel and grain size distribution in heat affected zone of the welded samples were investigated. Both similar and dissimilar arc welding operations were considered where in dissimilar welding joining of stainless steel to mild steel was examined. In the first stage, a three-dimensional model was developed to evaluate temperature field during and after arc welding while the model was performed using finite element software, ANSYS. Then, the effects of welding heat input and dissimilarity of the joint on the weld pool shape and grain growth in HAZ of stainless steel was investigated by means of model predictions and experimental observations. The results show that the similar joint produces wider HAZ and considerably larger grain size structure while in the dissimilar welds, the low carbon part acts as an effective heat sink and prevents the grain growth in the stainless steel side as well reduces the welding maximum temperature.

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Effect of Previous Grain Size on Recystallization Texture and the Formability of the Nb Ferritic Stainless Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.1594 ◽

2016 ◽

Vol 879 ◽

pp. 1594-1599

Author(s):

Daniella Gomes Rodrigues ◽

Cláudio Moreira Alcântara ◽

Dagoberto Brandão Santos ◽

Tarcísio Reis de Oliveira ◽

Berenice Mendonça Gonzalez

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Stainless Steel ◽

Ferritic Stainless Steel ◽

Longitudinal Section ◽

Tensile Tests ◽

Mechanical Tests ◽

Planar Anisotropy ◽

Electron Backscattered Diffraction ◽

R Value

The ferritic stainless steels are materials used in several segments due to the excellent combination of mechanical properties and corrosion resistance. The mechanical properties of these alloys are strongly dependent on the microstructural characteristics and crystallography texture. The aim of this experimental study is to investigate the roles of the grain size of the hot rolled sample on the development of the microstructure, texture and formability of ferritic stainless steel. The main elements of chemical composition of the steel under investigation were 16.0 %Cr, 0.021 %C, 0.024 %N and 0.35 %Nb. Coarse and fine grains samples were cold rolled up to 90% thickness reduction and annealed at 880°C with soaking time of the 24 s. The texture measurements were performed by Electron Backscattered Diffraction (EBSD) in the longitudinal section. The formability was evaluated by the R-value and planar anisotropy (Δr) in tensile tests. The final microstructure after annealed was more homogenous for smaller initial grain size sample. This condition was favorable to develop γ-fiber, with sharpness intensity in 111121 components. The highest R-value and smallest planar anisotropy was obtained for a {111}/{001} ratio around 5.37. On the other hand, coarser initial grain size sample had showed a heterogeneous microstructure and texture, performing badly in mechanical tests (anisotropy).

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Effect of Grain Size on the Anodic Dissolution of Lean Duplex UNS S32202 Austenitic-Ferritic Stainless Steel

CORROSION ◽

10.5006/3218 ◽

2019 ◽

Vol 75 (12) ◽

pp. 1450-1460

Author(s):

Charles David ◽

Fiona Ruel ◽

Florent Krajcarz ◽

Clément Boissy ◽

Saghi Saedlou ◽

...

Keyword(s):

Grain Size ◽

Stainless Steel ◽

Grain Boundary ◽

Ferritic Stainless Steel ◽

Anodic Dissolution ◽

Size Control ◽

Dissolution Behavior ◽

Boundary Density ◽

Electrochemical Testing ◽

Grain Size Control

The effect of grain size on the anodic dissolution of lean duplex UNS S32202 dual-phase austenitic-ferritic stainless steel was evaluated. Grain coarsening was achieved by heat treatment, and grain size and grain boundary densities determined by automatic image analysis after etching. Potentiodynamic electrochemical testing in acidic chloride medium allowed isolating the anodic dissolution behavior of the crystallographic phases of the material. A relationship between grain boundary density (for grain sizes in the micrometer range) and dissolution rate has been found, showing that reducing grain size enhances active corrosion rates in environments that promote active behavior. This leads to new possibilities of industrial adjustment of the corrosion behavior of duplex stainless steels via grain size control.

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Titanium Nitride and Niobium Carbide in the Ferritic Stainless Steel and the Influence to Casting Macrostructure

Materials Science Forum ◽

10.4028/www.scientific.net/msf.944.322 ◽

2019 ◽

Vol 944 ◽

pp. 322-328

Author(s):

Heng Ke Du ◽

Dian Xiu Xia ◽

Cheng Jia Shang ◽

Kun Chen

Keyword(s):

Grain Size ◽

Stainless Steel ◽

Titanium Nitride ◽

Ferritic Stainless Steel ◽

Niobium Carbide ◽

Equiaxed Crystal ◽

Corrosion Performance ◽

Solidification Processing ◽

Different Content

Titanium and niobium were applied to stable the carbon or nitrogen which dissolved ferritic stainless steel for improving the anti-corrosion performance. The titanium nitride and niobium carbide had been formed during solidification processing. For understanding those precipitates how to influence the casting macrostructure, three steels that had different content of niobium and the fixed content of titanium had been designed. The result showed the casting macrostructure of ingot and the grain size of the centre-equiaxed crystal zones had different tendency. And the titanium nitride and niobium carbide had interacted.

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Influence of Cold Working and Grain Size on Pitting Corrosion Resistance of Ferritic Stainless Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.217-218.1180 ◽

2011 ◽

Vol 217-218 ◽

pp. 1180-1184 ◽

Cited By ~ 4

Author(s):

Hua Bing Li ◽

Zhou Hua Jiang ◽

Qi Feng Ma ◽

Zhen Li

Keyword(s):

Grain Size ◽

Stainless Steel ◽

Corrosion Resistance ◽

Cold Rolling ◽

Ferritic Stainless Steel ◽

Pitting Corrosion ◽

Cold Working ◽

Rolling Reduction ◽

Pitting Corrosion Resistance ◽

Cold Rolling Reduction

The influence of cold working and grain size on the pitting corrosion resistance of Fe-Cr-Nb-Mo ferritic stainless steel is investigated using optical microscope and electrochemical methods. The pitting corrosion resistance firstly decreases with increasing the cold-rolling reduction from 0% to 30% due to the number of nucleation site increasing. With increasing the cold-rolling reduction from 40% to 60%, the disappearance of grain boundaries, stacked dislocation and uniform microstructure results in the pitting corrosion resistance of the steel. With prolonging the annealing time, the grain size of the steel grows, and the pitting potential of the steel decrease. The smaller grain size promotes the formation of compact passive film and improves the pitting corrosion resistance.

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