3D FEM Simulation to Predict the Heat Affected Zone during Laser Machining on Stainless Steel 304

This study addresses the effect of process parameters viz., loading ratio (mass of explosive/mass of flyer plate) and preset angle on dynamic bend angle, collision velocity and flyer plate velocity in dissimilar explosive cladding. In addition, the variation in interfacial microstructure and mechanical strength of aluminium 5052-stainless steel 304 explosive clads is reported. The interface exhibits a characteristic undulating interface with a continuous molten layer formation. The interfacial amplitude increases with the loading ratio and preset angle. Maximum hardness is observed at regions closer to the interface

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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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Evaluation of the residual stress in stainless steel 304L hydraulically expanded joints

Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering ◽

10.1177/0954408920964019 ◽

2020 ◽

pp. 095440892096401

Author(s):

Ying Hong ◽

Xuesheng Wang ◽

Yan Wang ◽

Zhao Zhang ◽

Yong Han

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Yield Strength ◽

Residual Stresses ◽

Heat Exchangers ◽

Nuclear Power ◽

The Finite Element Method ◽

Power Stations ◽

Stainless Steel 304 ◽

Initial Clearance

Stainless steel 304 L tubes are commonly used in the fabrication of heat exchangers for nuclear power stations. The stress corrosion cracking (SCC) of 304 L tubes in hydraulically expanded tube-to-tubesheet joints is the main reason for the failure of heat exchangers. In this study, 304 L hydraulically expanded joint specimens were prepared and the residual stresses of a tube were evaluated with both an experimental method and the finite element method (FEM). The residual stresses in the outer and inner surfaces of the tube were measured by strain gauges. The expanding and unloading processes of the tube-to-tubesheet joints were simulated by the FEM. Furthermore, an SCC test was carried out to verify the results of the experimental measurement and the FEM. There was good agreement between the FEM and the experimental results. The distribution of the residual stress of the tube in the expanded joint was revealed by the FEM. The effects of the expansion pressure, initial tube-to-hole clearance, and yield strength of the tube on the residual stress in the transition zone that lay between the expanded and unexpanded region of the tube were investigated. The results showed that the residual stress of the expanded joint reached the maximum value when the initial clearance was eliminated. The residual stress level decreased with the decrease of the initial tube-to-hole clearance and yield strength. Finally, an effective method that would reduce the residual stress without losing tightness was proposed.

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3D-FEM simulation model of the Earth-ionosphere cavity

Journal of Electromagnetic Waves and Applications ◽

10.1080/09205071.2019.1575289 ◽

2019 ◽

Vol 33 (6) ◽

pp. 734-742 ◽

Cited By ~ 2

Author(s):

E. S. Goncharov ◽

A. N. Lyakhov ◽

T. V. Loseva

Keyword(s):

Simulation Model ◽

Fem Simulation ◽

3D Fem ◽

The Earth

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Microstructure and Mechanical Properties of Heat-Affected Zone of Repeated Welding AISI 304N Austenitic Stainless Steel by Gleeble Simulator

Metals ◽

10.3390/met8100773 ◽

2018 ◽

Vol 8 (10) ◽

pp. 773

Author(s):

Y.H. Guo ◽

Li Lin ◽

Donghui Zhang ◽

Lili Liu ◽

M.K. Lei

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Austenitic Stainless Steel ◽

Impact Energy ◽

Heat Affected Zone ◽

Ferrite Content ◽

Equipment Safety ◽

Microstructure And Mechanical Properties ◽

Δ Ferrite ◽

The Impact

Heat-affected zone (HAZ) of welding joints critical to the equipment safety service are commonly repeatedly welded in industries. Thus, the effects of repeated welding up to six times on the microstructure and mechanical properties of HAZ for AISI 304N austenitic stainless steel specimens were investigated by a Gleeble simulator. The temperature field of HAZ was measured by in situ thermocouples. The as-welded and one to five times repeated welding were assigned as-welded (AW) and repeated welding 1–5 times (RW1–RW5), respectively. The austenitic matrices with the δ-ferrite were observed in all specimens by the metallography. The δ-ferrite content was also determined using magnetic and metallography methods. The δ-ferrite had a lathy structure with a content of 0.69–3.13 vol.%. The austenitic grains were equiaxial with an average size of 41.4–47.3 μm. The ultimate tensile strength (UTS) and yield strength (YS) mainly depended on the δ-ferrite content; otherwise, the impact energy mainly depended on both the austenitic grain size and the δ-ferrite content. The UTS of the RW1–RW3 specimens was above 550 MPa following the American Society of Mechanical Engineers (ASME) standard. The impact energy of all specimens was higher than that in ASME standard at about 56 J. The repeated welding up to three times could still meet the requirements for strength and toughness of welding specifications.

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