AVALIAÇÃO TRIBOLÓGICA DO CROMO DURO E TEXTURIZAÇÃO APLICADAS EM AÇOS PARA A FABRICAÇÃO DE CILINDROS DE LAMINAÇÃO A FRIO
TRIBOLOGICAL EVALUATION OF SURFACE TEXTURING AND HARD CHROMIUM COATING APPLIED TO COLD ROLLING MILLS ROLLS STEELS
Mello, José Daniel Biasoli; Gonçalves Junior, José Lucio
http://dx.doi.org/10.4322/tmm.2012.039
Tecnol. Metal. Mater. Min., vol.9, n4, p.336-344, 2012
Resumo
O presente trabalho analisa o comportamento tribológico de modificações superficiais geralmente utilizadas em cilindros para laminação a frio. Amostras provenientes de cilindros reais foram tratadas termicamente, retificadas e modificadas superficialmente (cromagem, texturização, cromagem com posterior texturização e texturização com posterior cromagem). Os testes tribológicos foram realizados em modo alternado de deslizamento, utilizando a configuração de esfera (Aço SAE 52100) – plano utilizando-se carga de 9,8 N. Observa-se que não há alteração significativa do coeficiente de atrito, em função das modificações superficiais, e que a texturização promove um aumento significativo no desgaste do contracorpo, enquanto o revestimento de cromo duro promove uma redução do mesmo. A adição do revestimento de cromo duro promove a formação de uma tribocamada no contracorpo constituída de cromo e oxigênio. Em contrapartida, em corpos sem o recobrimento de cromo duro, ocorre a formação de uma tribocamada constituída de ferro e oxigênio no corpo.
Palavras-chave
Tribologia, Laminação a frio, Cromo duro, Texturização
Abstract
The present work analyzes the tribological behavior of surface modifications often used in cold rolling mill rolls. Different surface modifications were carried out on samples produced from a fragment of the rolling mill roll: i) texturing; ii) chromium plating; iii) texturing with subsequent hard chrome plating; iv) and hard chrome plating with subsequent texturing. Before the surface modifications the samples were heat treated and ground on both faces. Wear tests were performed using a reciprocating movement of a ball over flat configuration under a load of 9.8 N. It is observed that there is no significant change in the coefficient of friction as a function of surface modification. Surface texturing increases the wear of the counter body, while the hard chromium coating reduces it. The addition of hard chromium coating promotes the formation of a tribolayer on the counter body consisting of chromium and oxygen. On the other hand, for the samples without hard chrome coating, the tribolayer consists of iron and oxygen.
Keywords
Tribology, Cold rolling mill roll, Hard chrome, Surface texturing
Referências
1 MENDES, J. L. T. Influência de parâmetros microestruturais no comportamento tribológico de ligas ferrosas
multicomponentes. 2007. 160 p. Tese (Doutorado em Engenharia Mecânica) – Faculdade da Universidade Federal de
Uberlândia, Uberlândia, 2007.
2 ELKOCA, O. A study on the characteristics of electrical discharge textured skin pass mill work roll. Surface and Coatings Technology, v. 202, n. 12, p. 2765-74, Mar. 2008. http://dx.doi.org/10.1016/j.surfcoat.2007.10.004
3 UTSCH, M.; VINKE, P. EDT: roll texturing technology as a base of modern surfaces in automotive cold mill flat products. Iron and Steel Techonology, v. 2, n. 9, p. 50-5, Apr. 2005.
4 SIMÃO, J.; ASPINWALL, D. K. Hard chromium plating of EDT mill work rolls. Journal of Materials Processing Technology, v. 92-93, p. 281-7, Aug. 1999. http://dx.doi.org/10.1016/S0924-0136(99)00124-7
5 CHIU, L. H. et al. Effect of contact pressure on wear resistance of AISI H13 tool steels with chromium nitride and hard chromium coatings. Surface and Coatings Technology, v. 154, n. 2-3, p. 282-8, May 2002. http://dx.doi. org/10.1016/S0257-8972(02)00011-7
6 KOVALCHENKO, A. et al. Friction and wear behavior of laser textured surface under lubricated initial point contact. Wear, v. 271, n. 9-10, p. 1719-1725, July 2011. http://dx.doi.org/10.1016/j.wear.2010.12.049
7 AHN, H.-S.; KWON, O.-K. Tribological behaviour of plasma-sprayed chromium oxide coating. Wear, v. 225-229, Part 2, p. 814-24, Apr. 1999. http://dx.doi.org/10.1016/S0043-1648(98)00390-1
8 ZUM GAHR, K. H.; MATHIEU, M.; BRYLKA, B. Friction control by surface engineering of ceramic sliding pairs in water. Wear, v. 263, n. 7-12, p. 920-9, Sep. 2007.
9 MILAN, J. C. G. et al. Effect of temperature, normal load and pre-oxidation on the sliding wear of multi-component ferrous alloys. Wear, v. 259, n. 1-6, p. 412-23, July-Aug. 2005.
2 ELKOCA, O. A study on the characteristics of electrical discharge textured skin pass mill work roll. Surface and Coatings Technology, v. 202, n. 12, p. 2765-74, Mar. 2008. http://dx.doi.org/10.1016/j.surfcoat.2007.10.004
3 UTSCH, M.; VINKE, P. EDT: roll texturing technology as a base of modern surfaces in automotive cold mill flat products. Iron and Steel Techonology, v. 2, n. 9, p. 50-5, Apr. 2005.
4 SIMÃO, J.; ASPINWALL, D. K. Hard chromium plating of EDT mill work rolls. Journal of Materials Processing Technology, v. 92-93, p. 281-7, Aug. 1999. http://dx.doi.org/10.1016/S0924-0136(99)00124-7
5 CHIU, L. H. et al. Effect of contact pressure on wear resistance of AISI H13 tool steels with chromium nitride and hard chromium coatings. Surface and Coatings Technology, v. 154, n. 2-3, p. 282-8, May 2002. http://dx.doi. org/10.1016/S0257-8972(02)00011-7
6 KOVALCHENKO, A. et al. Friction and wear behavior of laser textured surface under lubricated initial point contact. Wear, v. 271, n. 9-10, p. 1719-1725, July 2011. http://dx.doi.org/10.1016/j.wear.2010.12.049
7 AHN, H.-S.; KWON, O.-K. Tribological behaviour of plasma-sprayed chromium oxide coating. Wear, v. 225-229, Part 2, p. 814-24, Apr. 1999. http://dx.doi.org/10.1016/S0043-1648(98)00390-1
8 ZUM GAHR, K. H.; MATHIEU, M.; BRYLKA, B. Friction control by surface engineering of ceramic sliding pairs in water. Wear, v. 263, n. 7-12, p. 920-9, Sep. 2007.
9 MILAN, J. C. G. et al. Effect of temperature, normal load and pre-oxidation on the sliding wear of multi-component ferrous alloys. Wear, v. 259, n. 1-6, p. 412-23, July-Aug. 2005.
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