Hardened Case Properties and Tensile Behaviours of TMT Steel Bars

I.R. Kabir^1, and M.A. Islam¹

¹Materials and Metallurgical Engineering Department, BUET, Dhaka-1000, Bangladesh

Cite this paper:
I.R. Kabir and M.A. Islam. Hardened Case Properties and Tensile Behaviours of TMT Steel Bars. American Journal of Mechanical Engineering. 2014; 2(1):8-14. doi: 10.12691/ajme-2-1-2

Abstract

Nowadays, high strength steels are getting very popular all over the world for various applications such as in auto body making, machine parts manufacturing, steel structure buildings, concrete reinforcement, etc. In Bangladesh, use of high strength TMT steels bars has got a momentum in the construction of flyovers, bridges and high rise buildings because of its good combination of the required mechanical properties. In this research work, locally produced high strength TMT reinforcing steel bars (20 mm dia.) of two different companies have been investigated. As a part of this research work, at first, details microstructural morphologies of hardened case, transition zone and core of both steels were investigated by optical microscope and they were then photographed. After that, Rockwell hardness was measured on different zones. Tensile tests were also carried by a Universal Testing Machine at room temperature. After tensile tests, details of the fracture modes of the steel bars were studied carefully. The fracture modes were then discussed in terms of chemical compositions and carbon equivalents, resulted microstructures, case and core hardness, depths of hardened case and transition zone of the steel bars.

Keywords:
TMT steel hardened case fracture mode martensitic structures shear failure

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References:

[1]	D.L. Doushanov, “Control of Pollution in the Iron and Steel Industry”, Encyclopedia of Life Support Systems (EOLSS), vol.VIII, p.1-5.
[2]	TREBUŇA, P. , FIĽO, M., PEKARČÍKOVÁ, M.(2013), Supply and Distributin Logistics, AMOS Ostrava, 2.
[3]	TAKALA,J., MALINDŽÁK,D., STRAKA,M. (2007), Manufacturing strategy: Applying the logistics models / - Vaasa : Vaasan yliopisto - University of Vaasa.
[4]	Report on “Available and Emerging Technologies for Reducing Greenhouse Gas Emissions from the Iron and Steel Industry” by Office of Air and Radiation, United States Environmental Agency, September 2012.
[5]	Kopczynski, C., “High Strength Rebar Expanding Options in Concrete Towers”, Structure Magazine, vol.31, p.1-2, 2008.
[6]	BUDA,J., FIĽO,M. (2008), Manažment operácií, Prešov.
[7]	MARKOVIČ, J., JAMRICHOVÁ, S. (2008) Prosperujúci podnik v globálnom prostredí, Invent, Žilina.
[8]	Jha, G., Singh, A.K., Bandyopadhyay, N. and Mohanty, O.N., “Seismic Resistant Reinforcing Bars”, Journal of Practical Failure Analysis, ASM International, vol.5, p.53-56, 2001.
[9]	Fazal, S., Kwok, J. and Salah, O., “Application of High-Strength and Corrosion-Resistant ASTM A1035 Steel Reinforcing Bar in Concrete of High-Rise Construction”, The Council on Tall Buildings & Urban Habitat's, 8th World Congress, Dubai, p.1-6, 2008.
[10]	DURKÁČOVÁ, M. (2011), Balanced Scorecard - strategic management tool for company performance measurement. 15th International Student Conference on Electrical Engineering, Prague, ČVUT, P. 1-5.
[11]	BIELEFELDT, K., PAPACZ, W., WALKOWIAK, J. (2011), Environmentally friendly car plastics in automotive engineering. Part 1. Archiwum Motoryzacji = The Archives of Automotive Engineering , nr 2, s. 5-19 : bibliogr., rys., wykr., summ.
[12]	Bari, M.S., “Use of 500 Grade Steel in the Design of Reinforced Concrete Slab”, BSRM Seminar, p.1-19, 2008.
[13]	Noor, M.A. and Ahmed, A.U., “Study on Grade 75 and 60 Reinforcement in RC Design”, BSRM Seminar, p.1-12, 2008.
[14]	IVANKA, J. (2009), Automation systems and safety in intelligent buildings. In: Sborník příspěvků , mezinárodní konference ICMT´09, Brno, IDET, International Conference on Military Technologies, s. 225-234.
[15]	STARK, J.: Product Lifecycle Management, 21 st Century Paradigm for Product Realisation.
[16]	Takashi, M., Kawano, O., Hayashida, T., Okamoto, R. and Taniguchi, H. “High Strength Hot-rolled Steel Sheet for Automobiles”, Nippon Steel Technical Report No. 88, p.1-12, 2003.
[17]	Beynon, D., Jones, T.B. and Fourlaris, G., “Effect of High Strain Rate Deformation on Microstructure of Trip Steels Tested Under Dynamic Tensile Conditions”, Materials Science and Technology, vol.21, no.1, p.103-112, 2005.
[18]	SAAKSVUORI, A.-IMMONEN,A.: Product Lifecycle Management.
[19]	Tomota, Y., Tokuda, H, Adachi, Y., Wakita, M., Minakawa, N., Moriai, A. and Morii, Y., “Tensile Behavior of TRIP-aided Multiphase Steel Studied by In-situ Neutron Diffraction”, Acta Materialia, vol.52, p.5737-5745, 2004.
[20]	Hulka, K., “The Role of Niobium in Cold Rolled TRIP steel”, J. Materials Science Forum, vol.473, p.91-102, 2005.
[21]	Panigrahi, B.K., Srikanth, S. and Sahoo, G., “Effect of Alloying Elements on Tensile Properties, Microstructure and Corrosion Resistance of Reinforcing Bar Steel”, J. Mat. Engg. Perform. ASM International, vol.18, p.1102-1108, 2009.
[22]	Manoharan, R., Jayabalan, P. and Palanisamy, K., “Experimental Study on Corrosion Resistance of TMT Bar in Concrete”, ICCBT, p.239-250, 2008.
[23]	R. Datta, R Veeraraghavan and K.L. Rohira, “Weldability Characteristics of Torr and Corrosion-Resistant TMT Bars Using SMAW Process”, Journal of Materials Engineering and Performance, ASM International, vol.11, p.369-375, 2002.
[24]	P.C. Basu, P. Shylamoni and A.D. Roshan, “Characterization of steel Reinforcement for RC Structures: An Overview and Related Issue”, The Indian Concrete Journal, p.19-30, 2004.
[25]	B.K. Panigrahi, “Microstructure-Related Properties of Some Novel Reinforced Bar Steel”, Journal of Materials Engineering and Performance, ASM International, vol.19, p.287-293, 2010.
[26]	TMT bars manufacturing process: http://www.concretebasics.org/articlesinfo/tmt5.php.
[27]	B.K. Panigrahi and S.K. Jain, “Impact toughness of High Strength Low Alloy TMT Reinforcement Ribbed Bar”, Bulletin of Materials Science, vol.25, no.4, p.319-324, 2002.
[28]	M.A. Islam, “Low Temperature Fracture Toughness of Embrittled 2.25Cr-1Mo Pressure Vessel”, Ph.D Thesis, The University Of Birmingham, UK, 2001.
[29]	J.L. Evins, “Dependence of Strength on Corrosion-fatigue Resistance of AISI4130 Steel” Master Thesis, Georgia Institute of Technology, April 2004.
[30]	O. Kelestemur, M. Aksoy and S. Yildiz, “Corrosion behavior of tempered dual-phase steel embedded in concrete”, International Journal of Minerals, Metallurgy and Materials, vol.16, no.1, p.43-50, 2009.