Effect of Temper Rolling Reduction Ratio on Microhardness and Microstructure of DC04 Grade Sheet Material

Abstract

With temper rolling, which is the final stage of the cold rolling manufacturing process, to the surface of sheet metal materials is transferred roughness with specially roughened rolls. In this study, microhardness and microstructural evolution occurring in the section along the thickness of DC04 grade sheet materials temper rolled with various reduction ratios were investigated. As a result, it was concluded that the microhardness distribution taken from the section along the thickness increases with the increase of reduction ratio and the microhardness distribution from the surface to the center in the section decreases. In the temper rolling process with a reduction ratio of 250 µm and 500 µm an increase of approximately 5% and 15% has occurred, respectively compared to before the temper rolling process. It was also concluded that with the increase in reduction ratio, the grains in the section along the thickness elongated and thinned on the surface and this change in the center compared to the regions close to the surface was less.

Keywords

• Temper Rolling (Skin-Pass Rolling)
• Reduction Ratio
• Microhardness
• Microstructure
• DC04 Grade Sheet Materials

DC04 Kalite Sac Malzemenin Mikrosertlik ve Mikroyapısına Temper Haddeleme Ezme Miktarının Etkisi

Abstract

Soğuk haddeleme imalat prosesinin son aşaması olan temper haddeleme ile metal sac malzemelerin yüzeyine pürüzlülük, özel pürüzlendirilmiş merdaneler ile aktarılır. Bu çalışmada, farklı ezme miktarlarıyla haddelenmiş DC04 kalite sac metal malzemelerin, kalınlıkları boyunca kesitte meydana gelen mikrosertlik ve mikroyapısal değişim incelenmiştir. Sonuç olarak, kalınlık boyunca kesitten alınan mikrosertlik dağılımının ezme miktarının artmasıyla birlikte arttığı ve kesitte yüzeyden merkeze doğru mikrosertlik dağılımının azaldığı sonucuna varılmıştır. 250 µm ve 500 µm küçültme oranına sahip temper haddeleme işleminde, temper haddeleme işlemi öncesine göre sırasıyla yaklaşık %5 ve %15'lik bir artış meydana gelmiştir. Ayrıca ezme miktarının artmasıyla birlikte kalınlık boyunca kesitteki tanelerin yüzeyde uzayıp inceldiği ve merkezdeki bu değişimin yüzeye yakın bölgelere göre daha az olduğu sonucuna ulaşılmıştır.

Keywords

• Temper Haddeleme
• Ezme Miktarı
• Mikrosertlik
• Mikroyapı
• DC04 Kalite Sac Malzemeler

References

1. Kocańda A., Jasiński C. 2016. Extended evaluation of Erichsen cupping test results by means of laser speckle. Archives of Civil and Mechanical Engineering, 16: 211-216.
2. Mulay A., Ben B.S., Ismail S., Kocanda A., Jasiński C. 2018. Performance evaluation of high-speed incremental sheet forming technology for AA5754 H22 aluminum and DC04 steel sheets. Archives of Civil and Mechanical Engineering, 18: 1275-1287.
3. Aspinwall D.K., Wise M.L.H., Stout K.J., Goh T.H.A., Zhao F.L., El-Menshawy M.F. 1992. Electrical discharge texturing. International Journal of Machine Tools and Manufacture, 32 (1-2): 183-193.
4. Hilgenberg K., Steinhoff K. 2015. Texturing of skin-pass rolls by pulsed laser dispersing. Journal of Materials Processing Technology, 225: 84-92.
5. Xia C., Zhang X., Zhang J., Li H., Jia, S. 2017. Evolution on topography of textured work rolls and steel strips during cold rolling and temper rolling. Steel Research International, 88 (9): 1600469.
6. Burdek M. 2015. The change of work roll surface topography during skin pass rolling of steel sheets. Industrial Lubrication and Tribology, 67: 606-611.
7. Çolak B., Kurgan N. 2018. An experimental investigation into roughness transfer in skin-pass rolling of steel strips. The International Journal of Advanced Manufacturing Technology, 96 (9-12): 3321-3330.
8. Wu C., Zhang L., Qu P., Li S., Jiang Z. 2019. A new method for predicting the three-dimensional surface texture transfer in the skin pass rolling of metal strips. Wear, 426: 1246-1264.

9. Wu C., Zhang L., Qu P., Li S., Jiang Z. 2018. A simple approach for analysing the surface texture transfer in cold rolling of metal strips. The International Journal of Advanced Manufacturing Technology, 95 (1-4): 597-608.
10. Ma B., Tieu A.K., Lu C., Jiang Z. 2002. An experimental investigation of steel surface characteristic transfer by cold rolling. Journal of Materials Processing Technology, 125: 657-663.
11. Yu H., Lu C., Tieu K., Li H., Godbole A., Liu X., Kong C. 2019. Microstructure and mechanical properties of large-volume gradient-structure aluminium sheets fabricated by cyclic skin-pass rolling. Philosophical Magazine, 99 (18): 2265-2284.
12. Kijima H. 2013. Influence of roll radius on contact condition and material deformation in skin-pass rolling of steel strip. Journal of Materials Processing Technology, 213 (10): 1764-1771.
13. Grassino J., Vedani M., Vimercati G., Zanella G. 2012. Effects of skin pass rolling parameters on mechanical properties of steels. International Journal of Precision Engineering and Manufacturing, 13 (11): 2017-2026.
14. Koh Y.H., Lee M.H., Kim S.K. 2010. Texture evolution in low-C flat rolled steels on the physical properties. International Journal of Precision Engineering and Manufacturing, 11 (3): 445-452.
15. Ko Y.G., Chaudry U.M., Hamad K. 2020. Microstructure and mechanical properties of AA6061 alloy deformed by differential speed rolling. Materials Letters, 259: 126870.
16. Fuloria D., Kumar N., Goel S., Jayaganthan R., Jha S., Srivastava D. 2016. Tensile properties and microstructural evolution of Zircaloy-4 processed through rolling at different temperatures. Materials & Design, 103: 40-51.
17. Komerla K., Naumov A., Mertin C., Prahl U., Bleck W. 2018. Investigation of microstructure and mechanical properties of friction stir welded AA6016-T4 and DC04 alloy joints. The International Journal of Advanced Manufacturing Technology, 94 (9): 4209-4219.
18. Engler O. 1996. Nucleation and growth during recrystallisation of aluminium alloys investigated by local texture analysis. Materials Science and Technology, 12 (10): 859-872.