• Journal of Korea Foundry Society
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• v.26 no.4
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• pp.180-183
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• 2006

The effects of adding Ni on microstructure and mechanical properties of Nodular Indefinite Chilled Iron (NICI) were studied. Thermal fatigue, hardness, tensile properties, wear resistance, are very important factors for NICI used for hot working roll and wire rod mill. The results show that addition 4% nickel has changed pearlite to bainite. Bainite matrix is superior to pearlite matrix on wear resistance, hardness and strength and will increase performance lifetime of NICI conventional roll material. Based in the bainitic microstructure, hardness and tensile property increase up to 48 HRc and $72\;kg/mm^2$, respectively.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.04a
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• pp.111-114
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• 2009

Production of rolled steel has been growing partly supported by the advancement of rolls and rolling mills. Aiming at the further improvement in roll performance, various new techniques such as centrifugal casting, double poured casting cast steel, special build-up making, etc. have been introduced in the field of roll manufacture in these several years. The present paper describes the development of horizontal cast rolls(sleeve and indefinite chilled roll) made by Hyundai Steel and the results of mill tests. The developed roils are contributing the improvement of final products.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.08a
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• pp.223-230
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• 2004

In order to improve the productivity and quality of the hot rolled products, many morden mills have continuously required advanced roll materials. The introduction of HSS rolls in early stands of the Hot Strip Mill brought the excellent performance in wear resistance and surface roughness. Ni-grain rolls used in the later stands was needed to improve the roll performance. Therefore, the carbide reinforced Ni-grain roll was developed. The present paper will describe the development of carbide reinforced rolls made by INI STEEL and the results of mill tests. The wear resistance was increased upto $40\%$ and the anti-accident ablility was remarkably improved compared to the normal Ni-rain roll.