Electron Microscope Studies of the 01Cr17Ni13Mo3 Austenitic Steel Structure after Cold Rolling Combined with Hydrogen Alloying with Varying Degrees of Deformation

2022 ◽  
Vol 1049 ◽  
pp. 45-52
Author(s):  
Tatiana Kozlova
Keyword(s):  
Cold Rolling ◽  
Austenitic Steel ◽  
Large Angle ◽  
Steel Structure ◽  
Strength Properties ◽  
Martensite Phase ◽  
Rolling Temperature ◽  
Subgrain Structure ◽  
Twin Boundaries ◽  
Hydrogen Alloying

In this paper, we consider the effect of cold rolling and hydrogen alloying on the formation of twin boundaries of the corrosion resistance of austenitic steel 01Cr17Ni13Mo3. Using the method of transmission electronic microscopy, microdiffraction patterns were obtained. The analysis of microdiffraction patterns indicates the formation of a developed grain-subgrain structure with small-angle and large-angle misorientation. The structure has a high dislocation density, deformation twins and localized shift bands. It was established that plastic deformation by flat rolling to ε = 90 % at room temperature does not contribute to the appearance of a noticeable amount of α' and ε-martensite. At the temperature of liquid nitrogen, the samples were found to form a small fraction of the α'-martensite phase. Such a small amount of martensite can contribute to steel strengthening, and a decrease in the rolling temperature will lead to an increase in the strength properties of steel. It was detected that the density of twin boundaries under the decrease in the rolling temperature but with the same intensity of hydrogen saturation is significantly higher. A noticeable reduction in the width of the twin lamellas was revealed.

scholarly journals Microstructure and Mechanical Properties of an Austenitic CrMnNiMoN Spring Steel Strip with a Reduced Ni Content

Crystals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 392
Author(s):  
Christina Schröder ◽  
Marco Wendler ◽  
Olena Volkova ◽  
Andreas Weiß
Keyword(s):  
Mechanical Properties ◽  
Cold Rolling ◽  
Rolling Force ◽  
Steel Strip ◽  
Total Elongation ◽  
Strength Properties ◽  
Spring Steel ◽  
Rolling Temperature ◽  
Rolled Strip ◽  
Initial State

The article presents the mechanical properties of the austenitic stainless steel X5CrMnNiMoN16-4-4 after deformation by cold rolling and subsequent short-term tempering (deformation and partitioning (D&P) treatment). Tensile strengths of 1700–900 MPa and beyond were achieved both after work hardening and in the D&P-treated strip. The initial state of austenite in terms of grain size and pre-strengthening, as well as the selected cold rolling temperature significantly influenced the deformation-induced formation of α’ martensite and thus the flow and hardening behavior of the steel. The usage of two different rolling temperature regimes showed that the strength properties in the cold strip can be specifically adjusted. Lower deformation-induced martensite fractions enabled a larger thickness reduction of the strip without increasing the rolling force, while high deformation-induced martensite fractions led to strong hardening at low deformation levels. The D&P-treatment permits the strength of the cold-rolled strip with a predominantly austenitic microstructure to be increased to the required level. The total elongation of such a D&P strip was well over 2%. The D&P treatment of the spring steel strip is a cost-effective alternative to conventional tempering treatment.

scholarly journals Structural Transformations and Mechanical Properties of Metastable Austenitic Steel under High Temperature Thermomechanical Treatment

Metals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 645
Author(s):  
Igor Litovchenko ◽  
Sergey Akkuzin ◽  
Nadezhda Polekhina ◽  
Kseniya Almaeva ◽  
Evgeny Moskvichev
Keyword(s):  
Plastic Deformation ◽  
Grain Size ◽  
High Temperature ◽  
Austenitic Steel ◽  
Structural Transformations ◽  
Initial State ◽  
Twin Boundaries ◽  
Metastable Austenitic Steel ◽  
Average Grain Size ◽  
Heating Up

The effect of high-temperature thermomechanical treatment on the structural transformations and mechanical properties of metastable austenitic steel of the AISI 321 type is investigated. The features of the grain and defect microstructure of steel were studied by scanning electron microscopy with electron back-scatter diffraction (SEM EBSD) and transmission electron microscopy (TEM). It is shown that in the initial state after solution treatment the average grain size is 18 μm. A high (≈50%) fraction of twin boundaries (annealing twins) was found. In the course of hot (with heating up to 1100 °C) plastic deformation by rolling to moderate strain (e = 1.6, where e is true strain) the grain structure undergoes fragmentation, which gives rise to grain refining (the average grain size is 8 μm). Partial recovery and recrystallization also occur. The fraction of low-angle misorientation boundaries increases up to ≈46%, and that of twin boundaries decreases to ≈25%, compared to the initial state. The yield strength after this treatment reaches up to 477 MPa with elongation-to-failure of 26%. The combination of plastic deformation with heating up to 1100 °C (e = 0.8) and subsequent deformation with heating up to 600 °C (e = 0.7) reduces the average grain size to 1.4 μm and forms submicrocrystalline fragments. The fraction of low-angle misorientation boundaries is ≈60%, and that of twin boundaries is ≈3%. The structural states formed after this treatment provide an increase in the strength properties of steel (yield strength reaches up to 677 MPa) with ductility values of 12%. The mechanisms of plastic deformation and strengthening of metastable austenitic steel under the above high-temperature thermomechanical treatments are discussed.

scholarly journals Superelasticity Evaluation of the Biocompatible Ti-17Nb-6Ta Alloy

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Alaa Keshtta ◽  
Mohamed A.-H. Gepreel
Keyword(s):  
Fracture Surface ◽  
Cold Rolling ◽  
Shape Memory ◽  
Tensile Testing ◽  
Martensite Phase ◽  
Healthcare Applications ◽  
Ti Alloys ◽  
Alloy Microstructure ◽  
Two Phases ◽  
Rolling Deformation

Recently, studying the shape memory effect of the biocompatible Ti alloys takes much attention in the biomedical and healthcare applications. This study concerns about characterizing the superelasticity of the new biocompatible Ti-17Nb-6Ta (TNT) alloy. Microstructure of TNT was observed using optical and confocal microscopes. The alloy consists of two phases: β (predominant phase) and α″ martensite phase. The influence of cold rolling deformation on the microstructure was illustrated in which the martensitic-induced transformation appeared by cold rolling. The alloy is ductile as only the fracture dimples appeared in its fracture surface. Multicyclic loading and deloading tensile testing was applied to TNT specimens (flat and wire shapes) in order to evaluate the superelasticity. A superelastic strain as high as 3.5% was recorded for this TNT alloy. Therefore, TNT alloy has high potential for many biomedical and healthcare applications.

scholarly journals Microstructure and Mechanical Properties of 4Al Alumina-Forming Austenitic Steel after Cold-Rolling Deformation and Annealing

Materials ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 2767 ◽  
Author(s):  
Chenchen Jiang ◽  
Qiuzhi Gao ◽  
Hailian Zhang ◽  
Ziyun Liu ◽  
Huijun Li
Keyword(s):  
Grain Size ◽  
Cold Rolling ◽  
Grain Boundaries ◽  
Austenitic Steel ◽  
Rolling Reduction ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Cold Rolling Reduction ◽  
Average Grain Size ◽  
Cold Rolled

Microstructural evolutions of the 4Al alumina-forming austenitic steel after cold rolling with different reductions from 5% to 30% and then annealing were investigated using electron backscattering diffraction (EBSD), X-ray diffraction (XRD) and transmission electron microscopy (TEM). Tensile properties and hardness were also measured. The results show that the average grain size gradually decreases with an increase in the cold-rolling reduction. The low angle grain boundaries (LAGBs) are dominant in the cold-rolled samples, but high angle grain boundaries (HAGBs) form in the annealed samples, indicating that the grains are refined under the action of dislocations. During cold rolling, high-density dislocations are initially introduced in the samples, which contributes to a large number of dislocations remaining after annealing. With the sustaining increase in cold-rolled deformation, the samples exhibit more excellent tensile strength and hardness due to the decrease in grain size and increase in dislocation density, especially for the samples subjected to 30% cold-rolling reduction. The contribution of dislocations on yield strength is more than 60%.

Effect of Rolling Temperature, Reduction and Alloying Additions on the Texture of Warm Rolled Steels

2005 ◽  
Vol 495-497 ◽  
pp. 501-506 ◽  
Author(s):  
M. Sánchez-Araiza ◽  
Stéphane Godet ◽  
John J. Jonas
Keyword(s):  
Cold Rolling ◽  
Heating Rate ◽  
Warm Rolling ◽  
Carbon Steels ◽  
Rolling Temperature ◽  
Rolling Reduction ◽  
Low Carbon ◽  
Cold Rolling Reduction ◽  
Noticeable Improvement ◽  
Rolling Temperatures

The effect of warm and cold rolling parameters on the development of annealing textures was studied in two low carbon steels containing additions of chromium. Two warm rolling temperatures (640 and 700°C) were employed together with a reduction of 65%. The effects of an additional cold rolling reduction of 40% and of decreasing the heating rate during annealing were also studied. The ND fiber, <111>//ND, of the recrystallization texture was strengthened as the warm rolling temperature was decreased. However, all the warm rolled steels contained a retained RD fiber, <110>//RD. A noticeable improvement in both the continuity and intensity of the ND fiber was obtained when the sample was submitted to an additional 40% cold rolling reduction. The ND fiber was even more continuous and intense when a low heating rate was utilized, yielding r-values of 1.1 and 1.3 for the warm rolled and warm plus cold rolled samples, respectively.

Simulation Analysis and Structure Optimization of Steel Structure Climbing Formwork with Material Properties Used in the Large Angle Leaning Bridge Tower

2014 ◽  
Vol 540 ◽  
pp. 201-204
Author(s):  
Jian Ping Li ◽  
Jie Ruan ◽  
Pin Tan ◽  
Xian Jun Wang
Keyword(s):  
Maximum Stress ◽  
Simulation Analysis ◽  
Large Angle ◽  
Steel Structure ◽  
Angle Deviation ◽  
Uniform Cross Section ◽  
Strength And Stiffness ◽  
Stress And Deformation ◽  
And Control ◽  
Bridge Tower

Steel structure climbing formwork has been widely used in bridge pier and bridge tower, etc. But the design of 30 degrees slope climbing formwork design is rarely involved. The climbing formwork which in the upper surface of leaning bridge tower is affected by concrete buoyancy and the downside is affected by concrete gravity .That cause insufficient stiffness,deformation of the template,non-uniform cross-section of the bridge and large angle deviation which have great harm to the bridge quality .This paper which combined the construction project of Huaibei Xiangwang Bridge establish the mode of climbing formwork, then, import the mode to the Workbench14.5 proceeding simulation analysis. Getting the stress and deformation of the climbing formwork, check the strength and stiffness .Then optimize the structure of climbing formwork to ensure the stiffness and control the deformation of the template. The stress of downside climbing formwork after optimization is uniform and maximum stress is reduced about 30% .This paper provide a reference to the design of the climbing formwork used in the large angle leaning bridge tower.

scholarly journals EFFECT OF FRICTION ON THE MICROMECHANICAL PROPERTIES OF AISI 316L AUSTENITIC STEEL

2021 ◽  
Vol XXVIII (2) ◽  
pp. 34-43
Author(s):  
Daria Grabco ◽  
◽  
Constantin Pyrtsac ◽  
Daria Topal ◽  
Olga Shikimaka ◽  
...  
Keyword(s):  
Austenitic Steel ◽  
Resistance Index ◽  
Steel Structure ◽  
Aisi 316L ◽  
Near Surface ◽  
Fine Grained ◽  
316L Steel ◽  
Micromechanical Characteristics ◽  
Friction Method ◽  
Potential Use

In this paper, we investigate the possibility of using the friction method for modifying the microstructure and mechanical properties in the near-surface regions of AISI 316L austenitic steel specimens for the purpose of its practical application. It is shown that a region of severe plastic deformation arises near the friction surface, which transforms the initial fine-grained polycrystalline steel structure into a homogenized zone consisting of a deformed structure with plastic slip bands and weakly pronounced grain boundaries. The change in the microscopic structure results in an increase in this zone of values of micromechanical characteristics, such as microhardness (H), Young's modulus (E), plasticity index (H/E) and resistance index (H3/E2). The obtained results are of interest for the potential use of AISI 316L steel in medicine.

Effect of Mesostructural Elements on Radiation-Induced Porosity in 16Cr-19Ni-2Mo-2Mn-Nb-Ti-V-P-B Austenitic Steel

2019 ◽  
Vol 946 ◽  
pp. 357-361
Author(s):  
Vladimir I. Pastukhov ◽  
Irina A. Portnykh ◽  
Mikhail L. Lobanov
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Boundaries ◽  
Austenitic Steel ◽  
Neutron Irradiation ◽  
Steel Structure ◽  
Void Size ◽  
Orientation Microscopy ◽  
Radiation Induced ◽  
Scanning Electron

Different mesostructural elements of 16Cr-19Ni-2Mo-2Mn-Nb-Ti-B austenitic steel have been examined after neutron irradiation to damage dose up to 82 dpa by scanning electron microscopy using orientation microscopy (EBSD). Radiation porosity with maximum void size up to 200 nm was observed in austenitic steel structure after neutron irradiation. Nonuniformity, related to mesostructural elements, such as general grain boundaries, special CSL boundaries Σ3 (twins), areas with high density of low-angle boundaries, is typical for radiation porosity.

Laboratory Controlled Rolling of Microalloyed Steel for Production of Seamless Tubes

2016 ◽  
Vol 258 ◽  
pp. 611-614 ◽  
Author(s):  
Petr Kawulok ◽  
Radek Jurča ◽  
Ivo Schindler ◽  
Stanislav Rusz ◽  
Rostislav Turoň ◽  
...  
Keyword(s):  
Wall Thickness ◽  
Hsla Steel ◽  
Tensile Tests ◽  
Strength Properties ◽  
Controlled Rolling ◽  
Rolling Temperature ◽  
Plastic Properties ◽  
Finish Rolling Temperature ◽  
Finish Rolling ◽  
Rolling Temperatures

Using the laboratory rolling mill with smooth rolls, piercing, as well as rolling in a pilger mill of the seamless tubes with diameter 273 mm from the HSLA steel microalloyed with vanadium steel was simulated. Influence of the wall thickness (6.3 – 40 mm) and finish rolling temperature on the final structural and mechanical properties was investigated. Necessary temperatures of the phase transformations in the course of cooling were determined by dilatometric tests. Based on the dilatometry results, finish rolling temperatures were reduced. Lower rolling temperatures yielded in a relative grain refinement. Effect of the finish rolling temperature did not have any marked impact on the tensile tests results. Strength properties decreased only slightly with the increasing wall thickness and the plastic properties were not influenced significantly by this parameter. The positive effect of the reduced finishing temperature appeared markedly in the results of impact tests performed at room temperature only. Notch toughness was increased by approx. 25 % in the case of the wall thickness of not less than 20 mm.

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