Mathematical model of the electrocontact heating of a steel bar in the region of current-conducting electrodes

When conducting modal analysis to the structure with crack defect using ansys finite element, we usually adopt the method of cutting a rectangular notch to simulate the crack on the model structure. As a result, the different crack simulation requires repeated modeling, which is a waste of time, and we cannot guarantee the accuracy of the calculation. In this paper, mathematical model between the local stiffness and crack size is established based on the finite element simulation of a diameter of 8mm steel bar. Thus, we can simulate varisized crack defects through a fixed crack notch by the method of modifying local stiffness. The method we used is more simple and accurate than the traditionary one by cutting a rectangular notch to form cracks, and reduces the workload, and has certain research significances.

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Developing 1-D MM of Transient Industrial Quenched Chromium Steel-5147H to Study the Effect of Radius on Temperature History

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.711.115 ◽

2013 ◽

Vol 711 ◽

pp. 115-127

Author(s):

Badrul Omar ◽

Abdlmanam S.A. Elmaryami

Keyword(s):

Mechanical Properties ◽

Mathematical Model ◽

Finite Element ◽

Chromium Steel ◽

Temperature History ◽

Finite Element Software ◽

Steel Bar ◽

Proposed Model ◽

History Of ◽

The Impact

Mathematical modeling of an axisymmetric transient industrial quenched chromium steel bar AISI-SAE 5147H, water cooled based on finite element method has been produced to investigate the impact of process history on metallurgical and material properties. Mathematical modelling of 1-D line (radius) element axisymmetric model has been adopted to predict temperature history of the quenched chromium steel bar at any point (node). The temperature history of four different radii cylindrical geometry chromium steel 5147H is determined. The temperature history needs to be properly understood in order to efficiently produce high quality components. The model can be employed as a guideline to design cooling approach to achieve desired microstructure and mechanical properties such as hardness. The developed mathematical model converted to a computer program. This program can be used independently or incorporated into a temperature history calculator to continuously calculate and display temperature history of the industrial quenched chromium steel bar and thereby calculate the mechanical properties. The developed program from the mathematical model has been verified and validated by comparing its temperature simulation results with commercial finite element software results. The comparison indicates reliability of the proposed model.

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Developing 1D MM of Axisymmetric Transient Quenched Chromium Steel to Determine LHP

Journal of Metallurgy ◽

10.1155/2012/539823 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

Abdlmanam S. A. Elmaryami ◽

Badrul Omar

Keyword(s):

Mathematical Model ◽

Finite Element ◽

Chromium Steel ◽

Temperature History ◽

Finite Element Software ◽

Steel Bar ◽

History Of ◽

Quenched Steel ◽

The Impact ◽

The Mathematical Model

The modelling of an axisymmetric industrial quenched chromium steel bar AISI-SAE 8650H based on finite element method has been produced to investigate the impact of process history on metallurgical and material properties. Mathematical modelling of 1-dimensional line (radius) element axisymmetric model has been adopted to predict temperature history and consequently the hardness of the quenched steel bar at any point (node). The lowest hardness point (LHP) is determined. In this paper hardness in specimen points was calculated by the conversion of calculated characteristic cooling time for phase transformation t8/5 to hardness. The model can be employed as a guideline to design cooling approach to achieve desired microstructure and mechanical properties such as hardness. The developed mathematical model is converted to a computer program. This program can be used independently or incorporated into a temperature history calculator to continuously calculate and display temperature history of the industrial quenched steel bar and thereby calculate LHP. The developed program from the mathematical model has been verified and validated by comparing its hardness results with commercial finite element software results.

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Modelling of Heat Flow in Bundles of Round Steel Bars Including the Formation of Scale Layer

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.223.89 ◽

2014 ◽

Vol 223 ◽

pp. 89-99 ◽

Cited By ~ 1

Author(s):

Agnieszka Benduch ◽

Rafał Wyczółkowski ◽

Jan Jowsa

Keyword(s):

Heat Transfer ◽

Thermal Conductivity ◽

Mathematical Model ◽

Heat Flow ◽

Thermal Conduction ◽

Solid Phase ◽

Granular Structure ◽

Scale Layer ◽

Steel Bar ◽

Steel Bars

The article presents a proposal of a mathematical model describing the complex heat flow within the area of steel bar bundles. The model is based on an analysis of the thermal resistances defined for mechanisms of heat transfer present in the discussed medium. A bundle is considered a porous medium with a granular structure. Taking into account the modes of heat flow, we consider the following: thermal conduction in a solid phase (steel and scale), thermal conduction in a liquid phase (gas), and thermal radiation and the contact conduction in the areas of bar contact. The essence of the discussed model is the consideration of the phenomenon of scale, which is formed on the surface of the heated bars. The final result of the described calculation procedure is the value of the effective thermal conductivity kef. This parameter quantitatively expresses the heat flow in the area of the bars bundle and constitutes its basic thermal property. The value of kef is necessary for the optimization of heating a bundle of bars.

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