Role of Strain Gradient and Dynamic Transformation on the Formation of Nanocrystalline Structure Produced by Severe Plastic Deformation

Minoru Umemoto; Yoshikazu Todaka; Jin Guo Li; Koichi Tsuchiya

doi:10.4028/www.scientific.net/MSF.539-543.2787

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HomeMaterials Science ForumMaterials Science Forum Vols. 539-543Role of Strain Gradient and Dynamic Transformation...

Role of Strain Gradient and Dynamic Transformation on the Formation of Nanocrystalline Structure Produced by Severe Plastic Deformation

Abstract:

Formation of nanocrystalline structure by severe plastic deformation has studied extensively. Although ultra fine grained structure (grain size larger than 100 nm) had been obtained in many processes such as heavy cold rolling, equal channel angular pressing (ECAP) or accumulative roll bonding (ARB), the formation of nano grained structure (< 100 nm) is limited to processes such as ball milling, shot peening or drilling. In the present study, high pressure torsion (HPT) deformation and drilling were carried out to understand the conditions necessary to obtain nano grained structure in steels. The results of HPT experiments in pure Fe showed that HPT has superior ability of strengthening and grain refinement probably due to a strain gradient but the saturation of grain refinement occurs before reaching nano grained structure. Drilling experiments in high carbon martensitic steel revelaed that nano grained ferrite forms at the drilled hole surface only when the transformation from ferrite to austenite takes place during drilling. Considering various other processes by which nano grained ferrite was produced, it is proposed that heavy strains with large strain gradients together with dynamic transformation are necessary to reach nano grained ferrite structure.

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Periodical:

Materials Science Forum (Volumes 539-543)

Pages:

2787-2792

DOI:

https://doi.org/10.4028/www.scientific.net/MSF.539-543.2787

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Online since:

March 2007

Authors:

Minoru Umemoto, Yoshikazu Todaka, Jin Guo Li, Koichi Tsuchiya

Keywords:

Deformation, Grain, Nanocrystalline, Plastic, Steel, Structure, Transformation

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References

[1] J. Gil Sevillano : Proc. of 25th Riso International. Symposium on Materials Sciece (2004) p.1.

Google Scholar

[2] G. Sakai, Z, Horita, T. G. Langdon: Materials Science and Engineering A 393(2005) p.344.

Google Scholar

[3] D.R. Lesuer, C.K. Syn, O.D. Sherby: Materials Science and Engineering A 410-411 (2005) p.222.

Google Scholar

[4] Y. Ivanisenko, L. Maclaren, R.Z. Valiev, H.J. Fecht: Advanced Engineering Materials 11 (2005) p.1011.

Google Scholar

[5] Y. Todaka, M. Umemoto, S. Tanaka and K. Tsuchiya: Mater. Trans. 45 (2004) p.2209.

Google Scholar

[6] N. Kamikawa, N. Tsuji, T. Sakai and Y. Minamino: Proc. of the 25th RISO Int. Symp. on Mater. Sci., (2004) p.369.

Google Scholar

[7] H. Lin, C. Xu, B.Q. Han, E.J. Lavernia and T.G. Langdon : Proceeding of Ultrafine Grained Materials III TMS (2004) p.523.

Google Scholar

[8] A. Vorhauer, R. Pippan: Scripta Materialia 51 (2004) pp.921-925.

DOI: 10.1016/j.scriptamat.2004.04.025

Google Scholar

[9] N.A. Fleck, G.M. Muller, M.F. Ashby, J.W. Hutchinson: Acta Metall. Mater. 42(1994) p.475.

Google Scholar

[10] H. Fujiwara, H. Inomoto, R. Sanada and K. Ameyama: Scripta Materialia 44 (2001) pp. (2039).

DOI: 10.1016/s1359-6462(01)00858-2

Google Scholar