Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-27T12:12:07.440Z Has data issue: false hasContentIssue false
  • English
  • Français

Tensile testing of Al6061-T6 microspecimens with ultrafine grained structure derived from machining-based SPD process

Published online by Cambridge University Press:  25 June 2014

Paresh S. Ghangrekar ,
Ramprakash Banjare ,
Balkrishna C. Rao  and
H. Murthy
Paresh S. Ghangrekar
Affiliation:
Department of Aerospace Engineering, Indian Institute of Technology Madras, Chennai 600036, India
Ramprakash Banjare
Affiliation:
Department of Aerospace Engineering, Indian Institute of Technology Madras, Chennai 600036, India
Balkrishna C. Rao
Affiliation:
Department of Engineering Design, Indian Institute of Technology Madras, Chennai 600036, India
H. Murthy*
Affiliation:
Department of Aerospace Engineering, Indian Institute of Technology Madras, Chennai 600036, India
*
a) Address all correspondence to this author. e-mail: mhsn@ae.iitm.ac.in
Get access

Abstract

This paper discusses tensile testing of small samples of nanocrystalline Al6061-T6 alloy obtained from an unusual application of machining as a severe plastic deformation process. Ultrafine grained (UFG) shavings obtained from plane-strain cutting show higher hardness than the bulk material in agreement with existing literature. Application of restricted contact tools and extrusion-machining was explored to obtain shavings with minimum curvature to aid in tensile test specimen preparation. A novel method to prepare small tensile test specimens from these shavings has been described. During the tensile testing of UFG material, strains were measured using digital image correlation of natural speckles on the specimen. Specimens made from the UFG material had higher tensile strength and yield stress than the bulk, while ductility was lower. Lower values of Young's modulus were observed during the tensile testing of small specimens made from UFG as well as bulk material.

Keywords

severe plastic deformation (SPD)Al6061machiningultrafine grainedstraight chipstensile strength
Type
Articles
Information
Journal of Materials Research , Volume 29 , Issue 11 , 14 June 2014 , pp. 1278 - 1287
Copyright
Copyright © Materials Research Society 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Gleiter, H.: Nanocrystalline materials. Prog. Mater. Sci. 33, 223–315 (1989).Google Scholar
Siegel, R.: Creating nanophase materials. Sci. Am. 275, 74–79 (1996).Google Scholar
Valiev, R.Z., Korznikov, A.V., and Mulyukov, R.R.: Structure and properties of ultra-fine grained materials produced by severe plastic deformation. Mater. Sci. Eng., A 168, 141–148 (1993).Google Scholar
Embury, J. and Fisher, R.: The structure and properties of drawn pearlite. Acta Metall. 14, 147–159 (1966).Google Scholar
Langford, G. and Cohen, M.: Strain hardening of iron by severe plastic deformation. Trans. ASME 62, 623–638 (1969).Google Scholar
Valiev, R., Islamgaliev, R., and Alexandrov, I.: Bulk nanostructured materials from severe plastic deformation. Prog. Mater. Sci. 45,103–189 (2000).Google Scholar
Iwahashi, Y., Wang, J., Horita, Z., Nemoto, M., and Langdon, T.G.: Principle of equal-channel angular pressing for the processing of ultra-grained materials. Scr. Mater. 35(2), 143–146 (1996).Google Scholar
Segal, V.M.: Materials processing by simple shear. Mater. Sci. Eng., A 197, 157–164 (1995).Google Scholar
Ferrasse, S., Segal, V.M., Hartwig, K.T., and Goforth, R.E.: Development of a submicrometer-grained microstructure in aluminum 6061 using equal channel angular extrusion. J. Mater. Res. 12(5), 1253–1261 (1997).Google Scholar
Tham, Y.W., Fu, M.W., Hng, H.H., Pei, Q.X., and Lim, K.B.: Microstructure and properties of Al-6061 Alloy by equal channel angular extrusion for 16 passes. Mater. Manuf. Processes 22, 819–824 (2007).Google Scholar
Kim, J.K., Jeong, H.G., Hong, S.I., Kim, Y.S., and Kim, W.J.: The effect of aging treatment on heavily deformed microstructure of 6061 aluminum alloy after equal channel angular pressing. Scr. Mater. 45, 901–907 (2001).Google Scholar
Kim, J., Kim, H., Park, J., and Kim, W.: Large enhancement in mechanical properties of the 6061 Al alloys after a single pressing by ECAP. Scr. Mater. 53, 1207–1211 (2005).Google Scholar
Zhilyaev, A.P., Nurislamova, G.V., Kim, B-K., Baro, M.D., Szpunar, J.A., and Langdon, T.G.: Experimental parameters influencing the grain refinement and microstructural evolution during high-pressure torsion. Acta Mater. 51, 753–765 (2003).Google Scholar
Loucif, A., Figueiredo, R.B., Baudin, T., Brisset, F., and Langdon, T.G.: Microstructural evolution in an Al-6061 alloy processed by high-pressure torsion. Mater. Sci. Eng., A 527, 4864–4869 (2010).Google Scholar
Xu, C., Dobatkin, S.V., Horita, Z., and Langdon, T.G.: Superplastic flow in a nanostructured aluminum alloy produced using high-pressure torsion. Mater. Sci. Eng., A 500, 170–175 (2009).Google Scholar
Saito, Y., Tsuji, N., Utsunomiya, H., Sakai, T., and Hong, R.G.: Ultra-fine grained bulk aluminum produced by accumulative roll-bonding (ARB) process. Scr. Mater. 39(9), 1221–1227 (1998).Google Scholar
Kamikawa, N., Tsuji, N., Huang, X., and Hansen, N.: Quantification of annealed microstructures in ARB processed aluminum. Acta Mater. 54, 3055–3066 (2006).Google Scholar
Swaminathan, S., Ravi Shankar, M., Lee, S., Hwang, J., King, A.H., Kezara, R.F., Rao, B.C., Brown, T.L., Chandrasekar, S., Compton, W.D., and Trumble, K.P.: Large strain deformation and ultrafine grained materials by machining. Mater. Sci. Eng., A 410–411, 358–363 (2005).Google Scholar
Swaminathan, S., Ravi Shankar, M., Rao, B.C., Compton, W.D., Chandrasekar, S., King, A.H., and Trumble, K.P.: Severe plastic deformation (SPD) and nanostructured materials by machining. J. Mater. Sci. 42, 1529–1541 (2007).Google Scholar
Briesen, H., Fuhrmann, A., and Pratsinis, S.: Electrically assisted aerosol reactors using ring electrodes. Mater. Res. Soc. Symp. Proc. 520, 3–14 (1998).Google Scholar
Shaw, M.C.: Metal Cutting Principles, 2nd ed. (Oxford University Press, Clarendon, 1984).Google Scholar
Shankar, M.R., Chandrasekar, S., Compton, W.D., and King, A.H.: Characteristics of aluminum 6061-T6 deformed to large plastic strains by machining. Mater. Sci. Eng., A 410–411, 364–368 (2005).Google Scholar
Worthington, B. and Redford, A.: Chip curl and the action of the groove type chip former. Int. J. Mach. Tool Des. Res. 13, 257–270 (1973).Google Scholar
Jawahir, I.: The tool restricted contact effect as a major influencing factor in chip breaking: An experimental analysis. CIRP Ann.-Manuf. Technol. 37, 121–126 (1988).Google Scholar
Saldana, C., Swaminathan, S., Brown, T.L., Moscoso, W., Mann, J.B., Compton, W.D., and Chandrasekar, S.: Unusual applications of machining: Controlled nanostructuring of materials and surfaces. J. Manuf. Sci. Eng.-Trans. ASME 132, (2010).Google Scholar
ASTM Standard E407: ASTM International: West Conshohocken, PA, 2007.Google Scholar
Sergueeva, A., Zhou, J., Meacham, B., and Branagan, D.: Gage length and sample size effect on measured properties during tensile testing. Mater. Sci. Eng., A 526, 79–83 (2009).Google Scholar
Kammers, A.D. and Daly, S.: Small-scale patterning methods for digital image correlation under scanning electron microscopy. Meas. Sci. Technol. 22(12), 125501 (2011).Google Scholar