The role of back-pressure in equal channel angular extrusion
Source abstract
Abstract
Equal Channel Angular Extrusion (ECAE), developed and patented in Russia by Segal in 1977, has become in the last few years a very popular tool for studying the evolution of microstructure and properties under severe plastic deformation. It is believed that the strain-stress characteristics are uniform in a cross-section of the billet and this uniformity of the stress-strain distribution ensures the uniformity of microstructure and mechanical properties in ECAE processed billet. However, some experimental data such as the fracture of the extruded billet, which is initiated at the inner surface of the sample, has caused doubts about uniformity of stress-strain distribution. This non-uniformity has been proved recently by Finite Element Simulation. This paper reviewed our results from over six years of work using a unique machine for ECAE with computer controlled back-pressure and velocity of the backward punch. Theoretically back-pressure has been introduced in the earlier papers of Segal. However, practically back-pressure has not been widely used or often used in a primitive form of the consequent extruded sample and its role has not been understood.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Microstructure and mechanical properties · Metallurgy and Material Forming · Microstructure and Mechanical Properties of Steels
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References (20)
Show source-provided references
1. V. M. Segal, The Method of Material Preparation for Subsequent Working, Patent of the USSR, No. 575892, 1977.
2. ?Investigations and Applications of Severe Plastic Deformation,? edited by T. C. Lowe and R. Z. Valiev (NATO Science Series, Kluwer Academic Publishers, 2000).
3. NANOSPD, Proceedings of the 2nd International Conference on Nanomaterials by Severe Plastic Deformation: Fundamentals?Processing?Applications, Dec. 9?13, 2003, Wien, Austria (J. Wiley, VCH Weinheim, Germany, 2003).
4. V. M. Segal, Mater. Sci. Engng. A 271 (1999) 322.10.1016/S0921-5093(99)00248-8 ↗
5. J. R. Bowen, A. Gholinia, S. M. Roberts and P. B. Prangnell, ibid. A 287 (2000) 87.10.1016/S0921-5093(00)00834-0 ↗
6. R. E. Goforth, K. T. Hartwig and L. R. Cornwell, Severe Plastic Deformation of Material by Equal Channel Angular Extrusion, in ?Investigations and Applications of Severe Plastic Deformation,? edited by T. C. Lowe and R. Z. Valiev (NATO Science Series, Kluwer Academic Publishers, 2000) p. 3.10.1007/978-94-011-4062-1_1 ↗
7. J. Alkotra and J. G. Sevillano, J. Mater. Process. Techn. 141 (2003) 313.10.1016/S0924-0136(03)00282-6 ↗
8. S. J. Oh and S. B. Kang, Mater. Sci. Engng. A 343 (2003) 107.10.1016/S0921-5093(02)00324-6 ↗
9. S. L. Semiatin, D. P. DeLo and E. B. Shell, Acta Mater. 48 (2000) 1841.10.1016/S1359-6454(00)00019-7 ↗
10. D. P. DeLo and S. L. Semiatin, Deformation of Ti-6Al-4V via Equal Channel Angular Extrusion, Ultrafine Grained Materials II, edited by Y. T. Zhu, T. G. Langdon et al., TMS Meeting, 2002, p. 539.10.1002/9781118804537.ch61 ↗
11. V. M. Segal, V. I. Reznikov, A. E. Drobyshevskii and V. I. Kopylov, Izv. Akad. Nauk SSSR, Met. (1) (1981) 115 (in Russian).
12. R. Lapovok, Intern. J. Fract. 115(2) (2002) 159.10.1023/A:1016399111787 ↗
13. R. Ye. Lapovok, P. Wells, K. Raviprasad and P. W. J. McKenzie, ?Removal of Porosity in Cast Aluminium Alloys by ECAE, TERMEC?2003? (Trans. Tech. Publications Ltd., 2003) p. 297.10.4028/www.scientific.net/MSF.426-432.297 ↗
14. R. Lapovok, R. Cottam, G. Stecher, R. Deam and E. Summerville, Investigation of Ductility and Damage Accumulation by two Stage Deformation using ECAE/ECAD and Tensile Test, NATO Science Series Book ?Investigations and Applications of Severe Plastic Deformation,? 2000, p. 303.10.1007/978-94-011-4062-1_39 ↗
15. V. V. Stolyarov, R. Lapovok, I. G. Brodova and P. F. Thomson, Mater. Sci. Engng. A 357 (1/2) (2003) 159.10.1016/S0921-5093(03)00215-6 ↗
16. R. Ye. Lapovok and P. F. Thomson, Densification of Magnesium Particles by ECAP with a Back-Pressure, NANOSPD, in Proceedings of the 2nd International Conference on Nanomaterials by Severe Plastic Deformation: Fundamentals?Processing?Applications, Dec. 9?13, 2003, Wien, Austria (J. Wiley VCH Weinheim, Germany, 2003).
17. Q-Form User?s Guide, Quantor Ltd., 2000.
18. R. Lapovok, S. Smirnov and V. Shveykin, Inter. J. Fract. 103(2) (2000) 111.10.1023/A:1007593623392 ↗
19. R. Lapovok, S. Smirnov and V. Shveykin, Ductility Defined as Critical Local Strain, Proceedings of First Ausralasian Congress on Applied Mechanics, Melbourne, Australia, 1996, p. 181.
20. A. A. Bogatov, O. I. Miziridsky and S. V. Smirnov, Resource of Metal Plasticity in Metal Forming, Metallurgiya, Moskow, 1985 (in Russian).