Effect of ultrasonic surface rolling on surface characteristic of Mn13 high-Mn steel

The International Maritime Organization has recently updated the ship emission standards to reduce atmospheric contamination. One technique for reducing emissions involves using liquefied natural gas (LNG). The tanks used for the transport and storage of LNG must have very low thermal expansion and high cryogenic toughness. For excellent cryogenic properties, high-Mn steel with a complete austenitic structure is used to design these tanks. We aim to determine the optimum welding conditions for performing Laser-MIG (Metal Inert Gas) hybrid welding through the MIG leading and laser following processes. A welding speed of 100 cm/min was used for welding a 15 mm thick high-Mn steel plate. The welding performance was evaluated through mechanical property tests (tensile and yield strength, low-temperature impact, hardness) of the welded joints after performing the experiment. As a result, it was confirmed that the tensile strength was slightly less than 818.4 MPa, and the yield strength was 30% higher than base material. The low-temperature impact values were equal to or greater than 58 J at all locations in the weld zone. The hardness test confirmed that the hardness did not exceed 292 HV. The results of this study indicate that it is possible to use laser-MIG hybrid welding on thick high-Mn steel plates.

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3D-FEM Simulation of Hot Rolling Process and Characterization of the Resultant Microstructure of a Light-Weight Mn Steel

Crystals ◽

10.3390/cryst11050569 ◽

2021 ◽

Vol 11 (5) ◽

pp. 569

Author(s):

Ana Claudia González-Castillo ◽

José de Jesús Cruz-Rivera ◽

Mitsuo Osvaldo Ramos-Azpeitia ◽

Pedro Garnica-González ◽

Carlos Gamaliel Garay-Reyes ◽

...

Keyword(s):

Hot Rolling ◽

Thermomechanical Processing ◽

Computational Simulation ◽

Effective Strain ◽

Fem Simulation ◽

Rolling Process ◽

3D Fem ◽

Hot Rolling Process ◽

Mn Steel

Computational simulation has become more important in the design of thermomechanical processing since it allows the optimization of associated parameters such as temperature, stresses, strains and phase transformations. This work presents the results of the three-dimensional Finite Element Method (FEM) simulation of the hot rolling process of a medium Mn steel using DEFORM-3D software. Temperature and effective strain distribution in the surface and center of the sheet were analyzed for different rolling passes; also the change in damage factor was evaluated. According to the hot rolling simulation results, experimental hot rolling parameters were established in order to obtain the desired microstructure avoiding the presence of ferrite precipitation during the process. The microstructural characterization of the hot rolled steel was carried out using optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). It was found that the phases present in the steel after hot rolling are austenite and α′-martensite. Additionally, to understand the mechanical behavior, tensile tests were performed and concluded that this new steel can be catalogued in the third automotive generation.

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Competing deformation mechanisms in an austenite-ferrite medium-Mn steel at different strain rates

Materials Science and Engineering A ◽

10.1016/j.msea.2021.141357 ◽

2021 ◽

pp. 141357

Author(s):

Z.H. Cai ◽

D.L. Zhang ◽

L.F. Ma ◽

H. Ding ◽

Y. Feng ◽

...

Keyword(s):

Deformation Mechanisms ◽

Strain Rates ◽

Medium Mn Steel ◽

Mn Steel

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Surface Characteristic of Pure Titanium Sandblasted with Irregular Zirconia Particles and Acid-Etched

MATERIALS TRANSACTIONS ◽

10.2320/matertrans.m2011291 ◽

2012 ◽

Vol 53 (5) ◽

pp. 913-919 ◽

Cited By ~ 5

Author(s):

Shaobing Li ◽

Jia Ni ◽

Xiangning Liu ◽

Haibin Lu ◽

Shiheng Yin ◽

...

Keyword(s):

Pure Titanium ◽

Surface Characteristic

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High Efficiency Fluorinated Oligo(ethylenesuccinamide) Coating for Stone

Coatings ◽

10.3390/coatings11040452 ◽

2021 ◽

Vol 11 (4) ◽

pp. 452

Author(s):

Mara Camaiti ◽

Villiam Bortolotti ◽

Yijian Cao ◽

Alessandra Papacchini ◽

Antonella Salvini ◽

...

Keyword(s):

Porous Structure ◽

High Efficiency ◽

Surface Characteristic ◽

Surface Wettability ◽

Structure Evolution ◽

Potential Candidate ◽

Protective Agent ◽

Irradiation Test ◽

Improved Performance ◽

Photo Stability

The protection of stone cultural assets is related to the transformation of the surface characteristic from hydrophilic to hydrophobic/superhydrophobic through the application of a coating. The suitability of a coating depends not only on its capability to dramatically change the surface wettability, but also on other parameters such as the modification of kinetics of water absorption, the permanence of vapor diffusivity, the resistance of the coating to aging and the low volatile organic compound emissions during its application. In this work, an oligo(ethylensuccinamide) containing low molecular pendant perfluoropolyether segments (SC2-PFPE) and soluble in environmentally friendly solvents was tested as a protective agent for historic stone artifacts. Magnetic resonance imaging and relaxometry were employed to evaluate the effects of the surface wettability change, to follow the water diffusion inside the rock and to study the porous structure evolution after the application of SC2-PFPE. A sun-like irradiation test was used to investigate the photo-stability of the product. The results demonstrate that the highly photo-stable SC2-PFPE minimizes the surface wettability of the stone by modifying the water sorptivity without significantly affecting its porous structure and vapor diffusivity. The improved performance of SC2-PFPE in comparison to other traditional coatings makes it a potential candidate as an advanced coating for stone cultural heritage protection.

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Hot ductility behavior of a Fe-0.3C-9Mn-2Al medium Mn steel

International Journal of Minerals Metallurgy and Materials ◽

10.1007/s12613-020-2206-x ◽

2021 ◽

Vol 28 (3) ◽

pp. 422-429

Author(s):

Yong-jin Wang ◽

Shuai Zhao ◽

Ren-bo Song ◽

Bin Hu

Keyword(s):

Hot Ductility ◽

Medium Mn Steel ◽

Mn Steel

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Modelling of non-proportional hardening by dislocation based latent effects for SA333 Grade-6 C-Mn Steel

Materials Research Express ◽

10.1088/2053-1591/ab197d ◽

2019 ◽

Vol 6 (8) ◽

pp. 086562

Author(s):

S Bhattacharjee ◽

S Dhar ◽

S K Acharyya ◽

S K Gupta

Keyword(s):

Latent Effects ◽

Mn Steel

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Dynamic Transformation of Austenite at Temperatures above the Ae3

Materials Science Forum ◽

10.4028/www.scientific.net/msf.941.633 ◽

2018 ◽

Vol 941 ◽

pp. 633-638

Author(s):

John Joseph Jonas ◽

Clodualdo Aranas Jr. ◽

Samuel F. Rodrigues

Keyword(s):

Electron Microscopy ◽

Driving Force ◽

Energy Difference ◽

Accelerated Cooling ◽

Free Energy Difference ◽

Dynamic Transformation ◽

Plate Rolling ◽

Temperature Transformation ◽

Mn Steel ◽

Kinetics Of

Under loading above the Ae3 temperature, austenite transforms displacively into Widmanstätten ferrite. Here the driving force for transformation is the net softening during the phase change while the obstacle consists of the free energy difference between austenite and ferrite as well as the work of shear accommodation and dilatation during the transformation. Once the driving force is higher than the obstacle, phase transformation occurs. This phenomenon was explored here by means of the optical and electron microscopy of a C-Mn steel deformed above their transformation temperatures. Strain-temperature-transformation (STT) curves are presented that accurately quantify the amount of dynamically formed ferrite; the kinetics of retransformation are also specified in the form of appropriate TTRT diagrams. This technique can be used to improve the models for transformation on accelerated cooling in strip and plate rolling.

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