Effect of Deformation Temperature and Strain Rate on Evolution of Ultrafine Grained Structure through Single-Pass Large-Strain Warm Deformation in a Low Carbon Steel

The present work deals with grain refinement in low carbon steel (AISI 1010) by severe plastic deformation (SPD). The effect of structure modification was evaluated with respect to thermomechanical (TM) treatment of steel prior to SPD. The grain refinement was accomplished during warm angular channel pressing (ECAP) at 300°C. The evolution of microstructure during equal channel angular pressing (ECAP) was studied using SEM and TEM of thin foils. Ultrafine-grained structure development is described in relation to strainintroduced. At lower strain applied, the subgrain and/or polygonized structure was frequently found. Due to increased deformation temperature, the dynamic recovery contributed to structure refinement in both structural states. The amount of high angle boundaries increased with higher ECAP strain and was higher in TM-processed steel. There was only an indistinctive difference in structure refinement, considering different initial structures of the steel.The deformation behaviour of UFG steel in dependence on processing conditions was evaluated by a tensile test and correlated with structural characteristics.

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Computational Analysis of Compressive Strain Hardening Exponents of Bimetal with Pearlitic Steel and Low Carbon Steel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.553.71 ◽

2014 ◽

Vol 553 ◽

pp. 71-75 ◽

Cited By ~ 1

Author(s):

Xing Jian Gao ◽

Zheng Yi Jiang ◽

Dong Bin Wei ◽

Si Hai Jiao ◽

Jing Tao Han

Keyword(s):

Carbon Steel ◽

Strain Rate ◽

Strain Hardening ◽

Deformation Temperature ◽

Computational Analysis ◽

Compressive Strain ◽

Low Carbon Steel ◽

Pearlitic Steel ◽

Low Carbon ◽

Wide Range

The compressive strain hardening behaviour of a novel bimetal with pearlitic steel and low carbon steel was investigated by computational analysis based on the isothermal compression tests in a wide range of deformation temperature and strain rate. The Hollomon’s equation was employed to calculate the strain hardening exponent (SHE) with the assistance of mathematical manipulation. The result shows that the logarithmic relationship between the flow stress and plastic strain of the bimetal is highly non-linear, which results in the variation of the SHE of the bimetal. This variation reflects the dynamic competition between the strain hardening and softening mechanism by the varying value of the SHE in the range of 0.4 to-0.4. Furthermore, the influences of deformation temperature and strain rate on the SHE are significant. With decreasing temperature and increasing strain rate, the strain hardening of the bimetal was enhanced, while the dynamic recrystallisation was activated under the opposite conditions with the evidence of negative SHE value.

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Strength and impact toughness of low-carbon steel with fibrous ultrafine-grained structure

The Physics of Metals and Metallography ◽

10.1134/s0031918x14030107 ◽

2014 ◽

Vol 115 (3) ◽

pp. 295-302 ◽

Cited By ~ 11

Author(s):

I. M. Safarov ◽

A. V. Korznikov ◽

R. M. Galeev ◽

S. N. Sergeev ◽

S. V. Gladkovskii ◽

...

Keyword(s):

Carbon Steel ◽

Impact Toughness ◽

Low Carbon Steel ◽

Low Carbon ◽

Ultrafine Grained Structure ◽

Ultrafine Grained

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Effect of rolling reduction on ultrafine grained structure and mechanical properties of low-carbon steel thermomechanically processed from martensite starting structure

Science and Technology of Advanced Materials ◽

10.1016/j.stam.2003.10.017 ◽

2004 ◽

Vol 5 (1-2) ◽

pp. 153-162 ◽

Cited By ~ 75

Author(s):

Rintaro Ueji ◽

Nobuhiro Tsuji ◽

Yoritoshi Minamino ◽

Yuichiro Koizumi

Keyword(s):

Mechanical Properties ◽

Carbon Steel ◽

Low Carbon Steel ◽

Rolling Reduction ◽

Low Carbon ◽

Ultrafine Grained Structure ◽

Ultrafine Grained

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Microstructural Evolution during Simple Heavy Warm Deformation of a Low-Carbon Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.512.49 ◽

2006 ◽

Vol 512 ◽

pp. 49-54

Author(s):

S.V.S. Narayana Murty ◽

Shiro Torizuka ◽

Kotobu Nagai

Keyword(s):

Carbon Steel ◽

Strain Rate ◽

Compressive Strain ◽

Low Carbon Steel ◽

Processing Parameters ◽

Critical Conditions ◽

Low Carbon ◽

Compression Tests ◽

Warm Deformation ◽

Hollomon Parameter

We examined the microstructure development in low carbon steel (0.15% C) during heavy warm deformation (HWD) using field emission scanning electron microscopy (FESEM) and electron back-scattering diffraction (EBSD). Plane strain compression tests have been conducted in the temperature range of 773-923 K at strain rates of 0.01 s-1 and 1 s-1 with the specimens deformed to 25% of their original thickness. We summarize the strain rate and temperature into the Zener-Hollomon parameter and investigate its variation with plastic strain on the basis of the evolved microstructures and grain boundary character with a view to understanding the critical conditions for forming ultrafine grains and classifying them. Once established, these compressive strain-Z parameter plots simplify the selection of processing parameters (such as strain, strain rate, and temperature), towards achieving tailor-made microstructures in industrial components.

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