How to search?
advanced search

Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 4
items per page: 25 50 75
Sort by:

The cartographic development of the decision charts technique

Ireneusz Wyczałek
Geodesy and Cartography | 2001 | vol. 50 | No 3 | 149-157
Download PDF Download RIS Download Bibtex

Abstract

Among methods of solving decision matters the technique of decision charts has been presented in this paper and the idea of their cartographic development has been proposed. The problem has been described on the base of real application that concern of choosing a place on water intake for new arisen housing estate. The technique of colour scale for visualization of choice criteria and logical operations on colour images has been proposed in order to find the place which meet earlier formulated conditions in the best way. The results has been colected in modified decision chart. Next possibilities of development of the method have been indicated
Go to article

Authors and Affiliations

Ireneusz Wyczałek

Numerical analysis of SiGeSn/GeSn interband quantum well infrared photodetector

P. Pareek M.K. Das S. Kumar
Opto-Electronics Review | 2018 | vol. 26 | No 2 | 149-157
Keywords GeSn QWIP Strain balanced Sn composition Bandwidth Responsivity
Download PDF Download RIS Download Bibtex

Abstract

In this paper, detailed theoretical investigation on the frequency response and responsivity of a strain balanced SiGeSn/GeSn quantum well infrared photodetector (QWIP) is made. Rate equation and continuity equation in the well are solved simultaneously to obtain photo generated current. Quantum mechanical carrier transport like carrier capture in QW, escape of carrier from the well due to thermionic emission and tunneling are considered in this calculation. Impact of Sn composition in the GeSn well on the frequency response, bandwidth and responsivity are studied. Results show that Sn concentration in the GeSn active layer and applied bias have important role on the performance of the device. Significant bandwidth is obtained at low reverse bias voltage, e.g., 200 GHz is obtained at 0.28 V bias for a single Ge0.83Sn0.17 layer. Whereas, the maximum responsivity is of 8.6 mA/W at 0.5 V bias for the same structure. However, this can be enhanced by using MQW structure.

Go to article

Authors and Affiliations

P. Pareek
M.K. Das
S. Kumar

The Effect of Carbide Concentration at Grain Boundaries on Thermal Stresses in Castings for Heat Treatment Furnace Tooling

A. Bajwoluk P. Gutowski
Archives of Foundry Engineering | 2024 | vol. 24 | No 1 | 149-157 | DOI: 10.24425/afe.2024.149263
Keywords Cast grates thermal stresses Heat treatment equipment Thermal shock
Download PDF Download RIS Download Bibtex

Abstract

Austenitic Fe-Ni-Cr alloys are commonly used for the production of castings intended for high-temperature applications. One area where Fe-Ni-Cr castings are widely used is the equipment for heat treatment furnaces. Despite the good heat resistance properties of the materials used for the castings, they tend to develop cracks and deformations over time due to cyclic temperature changes experienced under high temperature operating conditions. In the case of carburizing furnace equipment, thermal stresses induced by the temperature gradient in each operating cycle on rapidly cooled elements have a significant influence on the progressive fatigue changes. In the carburized subsurface zone, also the different thermal expansion of the matrix and non-metallic precipitates plays a significant role in stress distribution. This article presents the results of analyses of thermal stresses in the surface and subsurface layer of carburized alloy during cooling, taking into account the simultaneous effect of both mentioned stress sources. The basis for the stress analyzes were the temperature distribution in the cross-section of the cooled element as a function cooling time, determined numerically using FEM. These distributions were taken as the thermal load of the element. The study presents the results of analyses on the influence of carbide concentration increase on stress distribution changes caused by the temperature gradient. The simultaneous consideration of both thermal stress sources, i.e. temperature gradient and different thermal expansions of phases, allowed for obtaining qualitatively closer results than analyzing the stress sources independently
Go to article

Bibliography

[1] Lai, G.Y. (2007). High-Temperature Corrosion and Materials Applications. ASM International.
[2] Davis, J.R. (1997). Industrial applications of heat-resistant materials. In Heat Resistant Materials. 67-85.
[3] Piekarski, B. (2012). Creep-resistant castings used in heat treatment furnaces. Szczecin: West Pomeranian University of Technology Publishing House. (in Polish).
[4] Lo, K.H., Shek, C. H., & Lai, J. K. L. (2009). Recent developments in stainless steels. Materials Science and Engineering R: Reports. 65(4-6), 39-104.
[5] Carreon, M., Ramos Azpeitia, M. O., Hernandez Rivera, J. L., Bedolla Jacuinde, A., Garcia Lopez, C. J., Ruiz Ochoa, J. A., & Gonzalez Castillo, A. C. (2023). Development of a novel heat-resistant austenitic cast steel with an improved thermal fatigue resistance. International Journal of Metalcasting. 17(2), 1114-1127. DOI: 10.1007/s40962-022-00838-1.
[6] Drotlew, A., Garbiak, M. & Piekarski, B. (2012). Cast steels for creep-resistant parts used in heat-treatment plants. Archives of Foundry Engineering, 12(4), 31-38. DOI: 10.2478/v10266-012-0103-0.
[7] Lekakh, S. N., Buchely, M., Li, M., & Godlewski, L. (2023). Effect of Cr and Ni concentrations on resilience of cast Nb-alloyed heat resistant austenitic steels at extreme high temperatures. Materials Science and Engineering: A. 873, 145027. DOI: doi.org/10.1016/j.msea.2023.145027.
[8] Piekarski, B. & Drotlew A. (2019). Cast grates used in heat treatment furnaces. Archives of Foundry Engineering, 19(3), 49-54. DOI: 10.24425/afe.2019.127138.
[9] Nandwana, D., Bhupendra, N. K., Bhargava, T., Nandwana, K., & Jawale, G. (2010). Design, Finite Element analysis and optimization of HRC trays used in heat treatment process. Proceedings of the World Congress on Engineering WCE 2010, (II), (pp. 1149-1154).
[10] Ul-Hamid, A., Tawancy, H. M., Mohammed, A. R. I., & Abbas, N. M. (2006). Failure analysis of furnace tubes exposed to excessive temperature. Engineering Failure Analysis. 13(6), 1005-1021. DOI: 10.1016/j.engfailanal. 2005.04.003.
[11] Piekarski, B. (2010). Damage of heat-resistant castings in a carburizing furnace. Engineering Failure Analysis. 17(1), 143-149. DOI: 10.1016/j.engfailanal.2009.04.011.
[12] Reihani, A., Razavi, S. A., Abbasi, E., & Etemadi, A. R. (2013). Failure analysis of welded radiant tubes made of cast heat-resisting steel. Journal of failure Analysis and Prevention. 13(6), 658-665. DOI: 10.1007/s11668-013-9741-y.
[13] Bochnakowski, W., Szyller, Ł. & Osetek, M. (2019). Damage characterization of belt conveyor made of the 330Nb alloy after service in a carburizing atmosphere in a continuous heat treatment furnace. Engineering Failure Analysis. 103, 173-183. DOI: 10.1016/j.engfailanal.2019.04.058.
[14] González-Ciordia, B., Fernández, B., Artola, G., Muro, M., Sanz, Á., & López de Lacalle, L. N. (2019). Failure-analysis based redesign of furnace conveyor system components: a case study. Metals. 9(8), 816, 1-12. DOI: 10.3390/met9080816.
[15] Srikanth, S., Saravanan, P., Khalkho, B., & Banerjee, P. (2021). Failure analysis of inconel 601 radiant tubes in continuous annealing furnace of hot dip galvanizing line. Journal of Failure Analysis and Preven-tion, 21. 747-758. DOI: 10.1007/s11668-021-01148-0.
[16] Gutowski, P. (1989). Analysis of cracking causes in grates used in carburising furnaces. Szczecin: Diss., Politechnika Szczecińska. (in Polish).
[17] Schnaas, A., Grabke, H.J. (1978). High-Temperature Corrosion and Creep of Ni-Cr-Fe Alloys in Carburizing and Oxidizing Environments. Oxidation of Metals. 12(5), 387-404. https://doi.org/10.1007/BF00612086.
[18] Zatorski, Z. & Tuleja, J. (2017). Numerical modelling of micro-stresses in carbonised austenitic cast steel under rapid cooling conditions. Archives of Metallurgy and Materials. 62(2), 635-641. DOI: 10.1515/amm-2017-0093.
[19] Bajwoluk, A. & Gutowski, P. (2019). Stress and crack propagation in the surface layer of carburized stable austenitic alloys during cooling. Materials at High Temperatures. 36(1), 9-18. DOI: 10.1080/09603409.2018144 8528.
[20] Bajwoluk, A. & Gutowski, P. (2017). The effect of cooling agent on stress and deformation of charge-loaded cast pallets. Archives of Foundry Engineering. 17(4), 13-18. DOI: 10.1515/afe-2017-0123.
[21] Bajwoluk, A. & Gutowski, P. (2018). Design options to decrease the thermal stresses in cast accessories for heat and chemical treatment furnaces. Archives of Foundry Engineering. 18(4), 125-130. DOI:10.24425/afe.2018. 125181.
[22] Bajwoluk, A. & Gutowski, P. (2019). Thermal stresses in the accessories of heat treatment furnaces vs cooling kinetics. Archives of Foundry Engineering. 19(3), 88-93. DOI: 10.24425/afe.2019.127146.
[23] Bajwoluk, A. & Gutowski, P. (2021). Effect of thermal nodes reduction in wall connections of the charge-handling furnace grates on thermal stresses. Archives of Foundry Engineering. 21(3), 53-58. DOI: 10.24425/afe.2021.138665.
[24] Tuleja, J., Kędzierska, K. & Sowa, M. (2022). The use of the finite element method to locate the places of damage occurrence in elements of technological equipment in carburizing furnaces. Procedia Computer Science. 207, 3931-3937. DOI: 10.1016/j.procs.2022.09.455.
[25] Bajwoluk, A. & Gutowski, P. (2023). Analysis of thermal stresses synergy in surface layer of carburised creep-resistant casts during rapid cooling processes. Materials at High Temperatures. 40(1), 64-76. DOI: 10.1080/09603409.2022. 2162684.
[26] Zienkiewicz, O.C. (1971). Finite element method in engineering science. London: McGraw-Hill.
[27] Midas NFX 2017: Analysis Manual, 2017.
[28] Standard PN-EN 10295: 2004. Heat resistant steel castings.
[29] Church, B. C., Sanders, T. H., Speyer, R. F., & Cochran, J. K. (2007). Thermal expansion matching and oxidation resistance of Fe–Ni–Cr interconnect alloys. Material Science and Engineering A. 452-453. https://doi.org/10.1016/j.msea.2006.10.149.
[30] Guo, X., Liu, Z., Li, L., Cheng, J., Su, H., & Zhang, L. (2022). Revealing the long-term oxidation and carburization mechanism of 310S SS and Alloy 800H exposed to supercritical carbon dioxide. Materials Chararacterization. 183, 111603. DOI: 10.1016/j.matchar.2021.111603.
[31] Shaffer, P.T.B.(1964). Plenum Press Handbooks Of High-Temperature Materials, Springer Science + Business Media.
[32] Schutze, M. (1997). Protective oxide scales and their breakdown. Ed. by D. R. Holmes, Institute of Corrosion, John Wiley & Sons.
[33] Huntz, A.M. (1995). Stresses in NiO, Cr2O3, and A2O3, oxide, Mater Science and Engineering A. 201 (1-2), 211-228. https://doi.org/10.1007/BF02648633.
[34] Richard, C. S., Béranger, G., & Decomps, F. (1995). Study of Cr203 coatings Part I: Microstructures and modulus. Journal of Thermal Spray Technology. 4(4), 342-346. https://doi.org/10.1007/BF02648633.
[35] Pang, X., Gao, K., & Volinsky, A. A. (2007). Microstructure and mechanical properties of chromium oxide coatings. Journal of Materials Research. 22(12), 3531-3537.
[36] Ji, A. L., Wang, W., Song, G. H., Wang, Q. M., Sun, C., & Wen, L. S. (2004). Microstructures and mechanical properties of chromium oxide films by arc ion plating. Materials Letters. 58(14), 1993-1998. https://doi.org/10.1016/j.matlet. 2003.12.029.
[37] Barshilia, H.C. & Rajam, K.S. (2008). Growth and characterization of chromium oxide coatings prepared by pulsed-direct current reactive unbalanced magnetron sputtering. Applied Surface Science. 255(9), 2925-2931. https://doi.org/10.1016/j.apsusc.2008.08.057.
[38] Gaillac, R., Pullumbi, P., & Coudert, F. X. (2016). ELATE: an open-source online application for analysis and visualization of elastic tensors. Journal of Physics: Condensed Matter. 28(27), 275201.
Go to article

Authors and Affiliations

A. Bajwoluk
1
ORCID: ORCID
P. Gutowski
1
ORCID: ORCID
  1. Mechanical Engineering Faculty, West Pomeranian University of Technology, Szczecin Al. Piastów 19, 70-310 Szczecin, Poland

Biographical sketch of Jerzy Ignacy Skowroński

Krystian Leonard Chrzan
Nauka | 2021 | No 1 | 149-157 | DOI: 10.24425/nauka.2021.136310
Keywords Jerzy Ignacy Skowroński electrical engineering high voltage insulation
Download PDF Download RIS Download Bibtex

Abstract

The life of Jerzy Ignacy Skowronski, Professor of High Voltages, Dean of the Faculty of Mechanical and Electrical Engineering and the first Dean of the Electrical Faculty of the Wrocław University of Science and Technology, member of the real Polish Academy of Sciences and President of the Wrocław Scientific Society, founder of the Wrocław Scientific School of Electrical Materials, was described. Documents contained in the Archives of the Wrocław University of Science and Technology, works published by Jerzy I. Skowronski, previously published publications on his scientific merits written by his former Ph.D. students and information from his grandson Jan Paweł Skowronski were used. The author's intention was to show unknown facts from the life of the Professor and his works unknown until now.
Go to article

Authors and Affiliations

Krystian Leonard Chrzan
1
  1. Politechnika Wrocławska

This page uses 'cookies'. Learn more