Electrochemical hydrogen permeation measurement through high-strength steel under uniaxial tensile stress in plastic range

Anisotropic plastic behavior of advanced high strength steel sheet of grade TRIP780 (Transformation Induced Plasticity) was investigated using three different yield functions, namely, the von Mises’s isotropic, Hill’s anisotropic (Hill’48), and Barlat’s anisotropic (Yld2000-2d) criterion. Uniaxial tensile and balanced biaxial test were conducted for the examined steel in order to characterize flow behavior and plastic anisotropy for different stress states. Especially, disk compression test was performed for obtaining balanced r-value. All these data were used to determine the anisotropic coefficients. As a result, yield stresses and r-values for different directions were calculated according to these yield criteria. The results were compared with experimental data. To verify the modelling accuracy, tensile tests of various notched samples were carried out and stress-strain distributions in the critical area were characterized. By this manner, the effect of stress triaxiality due to different notched shapes on the strain localization calculated by the investigated yield criteria could be studied.

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Studying the Effect of Manganese Content on TRIP Advanced High Strength Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.950.50 ◽

2019 ◽

Vol 950 ◽

pp. 50-54 ◽

Cited By ~ 1

Author(s):

Ahmed El-Sherbiny ◽

Ahmed Y. Shash ◽

Mohamed Kamal El-Fawkhry ◽

Tarek M. El-Hossainy ◽

Taha Mattar

Keyword(s):

High Strength Steel ◽

Retained Austenite ◽

Manganese Content ◽

High Strength ◽

Uniaxial Tensile ◽

Strain Hardening Exponent ◽

Uniaxial Tensile Test ◽

Advanced High Strength Steel ◽

High Manganese ◽

The Matrix

TRIP effect containing steel was well reputed by its high mechanical properties among the 1st generation of Advanced High Strength Steel. High Silicon content was well established as an inhibitor for cementite precipitation at para-equilibrium condition. However, the effect of manganese as a powerful stabilizer for retained austenite was not much studied in TRIP-Steel. Thereby, the effect of high manganese content on the TRIP containing steel is studied in this research. As been observed from OM, and XRD results, it was found that as long as increasing Manganese content, the fraction of retained austenite increases. No doubt that enrichment of retained austenite throughout the matrix, beers a great impact on the plastic deformation character of the investigated steels, which was proved by using a uniaxial tensile test and determining the strain hardening exponent.

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Mechanical behaviour and structure of snow under uniaxial tensile stress

Journal of Glaciology ◽

10.1017/s0022143000010819 ◽

1980 ◽

Vol 26 (94) ◽

pp. 275-282 ◽

Cited By ~ 62

Author(s):

Hidek Narita

Keyword(s):

Tensile Stress ◽

Strain Rate ◽

Mechanical Behaviour ◽

Maximum Strength ◽

Ductile Deformation ◽

Uniaxial Tensile ◽

Strain Rates ◽

Thin Sections ◽

Uniaxial Tensile Stress ◽

Small Cracks

AbstractThe mechanical behaviour of snow was studied at — 10°C under uniaxial tensile stress in a range of cross-head speed 6.8 × 10–8to 3.1 × 10–4ms–1and snow density 240-470 kg m–3.It was found from the resisting force-deformation curves that the snow was deformed in two different ways: namely, brittle and ductile deformation at high and low strain-rates, respectively. The critical strain-rate dividing the two deformation modes was found to depend on the density of snow. In ductile deformation, many small cracks appeared throughout the entire specimen. Their features were observed by making thin sections and they were compared with small cracks formed in natural snow on a mountain slope.The maximum strength of snow was found to depend on strain-rate: at strain-rates above about 10–5s–1, the maximum strength increased with decreasing strain-rate but below 10–5s–1it decreased with decreasing strain-rate.

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Mechanical behaviour and structure of snow under uniaxial tensile stress

Journal of Glaciology ◽

10.3189/s0022143000010819 ◽

1980 ◽

Vol 26 (94) ◽

pp. 275-282 ◽

Cited By ~ 3

Author(s):

Hidek Narita

Keyword(s):

Tensile Stress ◽

Strain Rate ◽

Mechanical Behaviour ◽

Maximum Strength ◽

Ductile Deformation ◽

Uniaxial Tensile ◽

Strain Rates ◽

Thin Sections ◽

Uniaxial Tensile Stress ◽

Small Cracks

AbstractThe mechanical behaviour of snow was studied at — 10°C under uniaxial tensile stress in a range of cross-head speed 6.8 × 10–8 to 3.1 × 10–4 ms–1 and snow density 240-470 kg m–3.It was found from the resisting force-deformation curves that the snow was deformed in two different ways: namely, brittle and ductile deformation at high and low strain-rates, respectively. The critical strain-rate dividing the two deformation modes was found to depend on the density of snow. In ductile deformation, many small cracks appeared throughout the entire specimen. Their features were observed by making thin sections and they were compared with small cracks formed in natural snow on a mountain slope.The maximum strength of snow was found to depend on strain-rate: at strain-rates above about 10–5 s –1, the maximum strength increased with decreasing strain-rate but below 10–5 s–1 it decreased with decreasing strain-rate.

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