• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.60-61
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• 2016

Performance has been developed in terms of structural strength. Especially, in a structural steels, it is regarded as a common design process that an yield stress of thicker plate than 40mm uses that of below 40mm in thickness. This can be done using TMCP(Thermo mechanical control process). In this study, the structural stabilities such as deflection, maximum load carrying capacity would be calculated in high temperatures.

• Nuclear Engineering and Technology
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• v.54 no.6
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• pp.2173-2187
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• 2022

A 3D thermo-elasto-hydrodynamic model is developed to analyze the sealing performance of a notched mechanical seal applied in the reactor coolant pump. In the model, the generalized Reynolds equation, the energy equation coupled with notch heat balance equation, the heat conduction equations, and the deformation equations of the sealing rings are iteratively solved by the finite element method. The film pressure and temperature distribution are obtained, and the deformation of the sealing rings is revealed to study the mechanism of the notched mechanical seals. A parameterized study is conducted to analyze the sealing performance under different operating conditions. As a comparison, the sealing performance of non-notched seals is also studied. The results show that the hydrostatic effect is dominant in the load-carrying capacity of the fluid film due to the radial mechanical and thermal deformations. The notch can cool the fluid film and influence the thermal deformation of seal rings. The sealing performance is sensitive to the pressure difference, ambient temperature, and rotational speed. It is suggested to set the notches on the softer sealing rings to acquire the greater hydrodynamic effect. Compared with the non-notched, the notched end face holds a better lubrication performance, especially under lower rotational speed.

• Fire Science and Engineering
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• v.27 no.6
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• pp.21-25
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• 2013

Fire resistance steel, grading 490 MPa, had developed by using Thermo-mechanical control process (TMCP) and it has better performance at welding, seismic resistance than those of the ordinary structural steel, But the fire resistance performance is required to verify against the ordinary fire resistance, FR 490. Therefore this study was done to make database of mechanical properties at high temperature and to evaluate the structural stability at high temperature in terms of materials and structural member such as H-section from that of FR 490. The result of this study was that the structural stability of TMCP was lower than that of ordinary FR 490 at the range up about $700^{\circ}C$.

• Proceedings of the KWS Conference
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• 1990.04a
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• pp.135-136
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• 1990

• Journal of Korean Society of Steel Construction
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• v.15 no.3
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• pp.331-339
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• 2003

The study discussed in this paper investigated the material characteristics for the Thermo-Mechanical Control Process(TMCP) plates, which are controlled by several factors such as rolling, cold-stripping, cooling rate, and fixed carbon quantity. The suitability of thick TMCP steel plates as structural steel was also estimated through several experiments and with the us of a statistical method to analyze mill certificate sheets provided by the manufacturer. The results of this study are as follows: the TMCP steel plates showed stable values of the composition parameter ($P_cm$) and the carbon equivalents ($C_eq$ ) with satisfied yield strength, ultimate strength, and low-yield ratio.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.08a
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• pp.175-183
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• 2004

In hot strip rolling, a capability for precisely predicting roll force is crucial for sound process control. In the past, on-line prediction models have been developed mostly on the basis of Orowan's theory and its variation. However, the range of process conditions in which desired prediction accuracy could be achieved was rather limited, mainly due to many simplifying assumptions inherent to Orowan's theory. As far as the prediction accuracy is concerned, a rigorously formulated finite element(FE) process model is perhaps the best choice. However, a FE process model in general requires a large CPU time, rendering itself inadequate for on-line purpose. In this report, we present a FE-based on-line prediction model applicable to precision process control in a finishing mill(FM). Described was an integrated FE process model capable of revealing the detailed aspects of the thermo-mechanical behavior of the roll-strip system. Using the FE process model, a series of process simulation was conducted to investigate the effect of diverse process variables on some selected non-dimensional parameters characterizing the thermo-mechanical behavior of the strip. Then, it was shown that an on-line model for the prediction of roll force could be derived on the basis of these parameters. The prediction accuracy of the proposed model was examined through comparison with measurements from the hot strip mill.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.4
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• pp.53-60
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• 2003

Large sized marine structures are used under corrosion environment of seawater and applied by severe service loading such as an ocean current, a billow and a tempest. Marine structures are usually constructed by lots of thick wall steel pipes joining welded joints. The thickness of such as steel pipes is usually more than 40mm. The such as steels are called "Thermo-Mechanical Control Process steel (TMCP steel)" strengthened by a heat treatment in process of steel manufactures. The failure, especially crack initiation, of marine structures was starting at weld joints under service condition. Then they should be designed by basis of the fatigue strength under seawater corrosion environment of weld joints. To clarity the fatigue crack initiation behavior is important more than to clarify the crack propagation behavior on the strength design of marine structures, because it is very difficult to find out the crack initiation and propagation phenomena and then even if it will be able to find out, it is considered that the refit of the damaged parts of welded joints have a technical difficulty under the sea. Therefore, it is most important to clarify the corrosion fatigue crack initiation behavior under the seawater condition. But, there is one big difficulty to make a test for thick plate specimen, for example thicker than 40mm. Because, it is need large capacity loading apparatus to test such as thick plate specimen. In this research, the new configuration specimen for fatigue crack initiation tests was proposed. Using this new specimen, it is easy to carry out the fatigue clack initiation tests with relatively low cyclic loading and to observe a fatigue crack initiation behavior.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.1
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• pp.87-94
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• 2023

TMCP(Thermo Mechanical Control Process) steel was continuously cast (CC) by varying the argon gas flow rate and vacuum time in the Ruhrstahl Heraeus (RH) refining process. Using the CC specimens, the distribution of the inclusions and the mechanical properties were evaluated. A lot of oxides and Al-O type inclusions were observed. The average Vickers hardness did not show a constant, but showed dispersion in a certain range. The shape and scale parameters of the CC specimen with an argon gas flow rate of 160Nm³ and a vacuum time of 12 minutes was the best. Mechanical properties (tensile strength, yield strength and elongation) were consistent with the Weibull probability distribution analysis results. The impact resistance was the best for CC specimens with an argon flow rate of 140 Nm³ and a vacuum time of 12 minutes. Although the inclusions and mechanical properties of the CC specimens were evaluated according to the argon gas flow rate and vacuum time, these values were no significant difference.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.1
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• pp.45-50
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• 2011

Hot-Press-Forming (HPF), an advanced sheet metal forming method using stamping at a high temperature of about $900^{\circ}C$ and quenching in an internally cooled die set, is one of the most successful forming process in producing crash-resistant parts such as pillars and bumpers with complex shape, ultrahigh strength, and minimum springback. To optimize conditions of a forming quality in HPF process and secure a safe product without any failures, such as fractures and wrinkling, the simulations based on the coupled thermo-mechanical analysis for a hot-press-formed lower control arm are applied with Taguchi's orthogonal array experiment. Three factor variables - the friction coefficient, blank shape, and hole location for burring - are selected to be optimized. The most effective condition of a forming quality for a hot-press-formed lower control arm is suggested. The simulation results are confirmed with experimental ones.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.05a
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• pp.136-142
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• 2001

Recently, a much amount of attention has been paid not only to produce products with precise dimensional accuracy, but also to predict and control the microstructural evolution and mechanical properties of parts. Especially, to do the latter through computer simulation, the history of states factors influencing on these evolution such as temperature, strain, strain rate etc., should be calculated and a appropriate mathematical models for the prediction of microstructural evolution must be developed. Thus, in this study thermo-viscoplastic finite element program including the model for predicting microstructural has been developed. Also for the verification of developed program warm forging process for the rotor pole was simulated and the comparison between the results calculated and ones in the literature was made.