Improvement in Mechanical Properties of Titanium Deformed by ECAE Process

Document Type : Original Research Paper


1 Mechanical Engineering Department, Faculty of Engineering, Bu-Ali Sina University, Hamadan, Iran.

2 Department of Mechanical and Manufacturing Engineering, University Putra Malaysia, Malaysia.

3 School of Mechanical Engineering, Islamic Azad University, Takestan Branch, Takestan, Iran.


In this study, annealed CP-Ti (Grade 2) was processed by Equal Channel Angular Extrusion (ECAE) up to 2 passes at a temperature of 400C following route A with a constant ram speed of 30 mm/min through a die angle of 90◦ between the die channels. Mechanical properties of the extruded materials were obtained at different strain rates. The results indicated that the tensile yield stress and ultimate tensile strength of the extruded specimens increased significantly after 2 passes of ECAE process. The maximum increase for yield stress was around 90% which occurred at the pulling rate of 0.5 mm/min. The bending fatigue life of the extruded specimens improved significantly so that in low cycle fatigue regime a 700% increase in fatigue life was observed after two ECAE passes. The improvement was lower in high cycle fatigue regime. The microhardness measurement of the specimens indicated that the average microhardness of the samples increased about 140% after 2 passes. The fracture mechanism of the ECAE specimens was also studied by fractography of the fracture surface of specimens. Microstructure of the extruded specimens was also examined by optical microscopy.


[1] ASME I. Properties and Selection: Nonferrous Alloys and Special-Purpose Materials, ASME Handbook, 2 (1990) 592-593.
[2] R. Chaudhari, R. Bauri, Microstructure and Mechanical Properties of Titanium Processed by Spark Plasma Sintering (SPS), Metallurgic Microstructure anu. 3 (2014) 30-35.
[3] G. Purcek, O. Saray, O. Kul, I. Karaman, G.G. Yapici, M. Haouaoui, H.J. Maier, Mechanical and wear properties of ultrane-grained pure Ti produced by multi-pass equal-channel angular extrusion, Mater. Sci. Eng. A. 517 (2009) 97-104.
[4] V.P. Basavaraj, U. Chakkingal, T.S.P. Kumar, Study of channel, angle inuence on material ow and strain inhomogeneity in equal channel angular pressing using 3D nite element simulation, J. Mater. Process. Tech. 209 (2009) 89-95.
[5] I. Kim, J. Kim, D.H. Shin, C.S. Lee, S.K. Hwang, Effects of equal channel angular pressing temperature on deformation structures of pure Ti, Mater. Sci. Eng. 342 (2003) 302-310.
[6] Y.W. Tham, M.W. Fu, H.H. Hng, M.S. Yong, Lim KB, Study of deformation homogeneity in the multi-pass equal channel angular extrusion process, J. Mater. Process. Tech. 192 (2007) 121-127.
[7] V.M. Segal, Materials processing by simple shear. Mater. Sci. Eng. 197 (1995) 157-164.
[8] E. Cerri, P.P. De Marco, P. Leo, FEM and metallurgical analysis of modied 6082 aluminium alloys processed by multi pass ECAP: Inuence of material properties and different process settings on induced plastic strain, J. Mater. Process. Tech. 209 (2009) 1550-1564.
[9] R. Luri, C.J. Luis Prez, D. Salcedo, I. Puertas, J. Len, I. Prez, J.P. Fuertes, Evolution of damage in AA-5083 processed by equal channel angular extrusion using different die geometries, Mater. Des. 211 (2011) 48-56.
[10] Q. Jianhui, M. Takuya, W. Xueli, K. Masayoshi, Plastic deformation mechanism of crystalline polymer materials in the equal channel angular extrusion process, J. Mater. Process. Tech. 212 (2012) 1528-1536.
[11] J. Jiang, Y. Wang, Z. Du, J. Qu, Y. Sun, L. Shoujing, Enhancing room temperature mechanical properties of Mg-9Al-Zn alloy by multi-pass equal channel angular extrusion, J. Mater. Process. Tech. 210 (2010) 751-758.
[12] M.H. Shaeri, F. Djavanroodi, M. Sedighi, S. Ahmadi, M.T. Salehi, SH. Seyyedein, Effect of copper tube casing on strain distribution and mechanical properties of Al-7075 alloy processed by equal channel angular pressing, J. Strain. Anal. Eng. Des. 48
(2013) 512-521.
[13] M. Ebrahimi, B. Rajabifar, F. Djavanroodi, New approaches to optimize strain behavior of Al6082 during equal channel angular pressing, J. Strain. Anal. Eng. Des. 48 (2013) 395-404.
[14] D.H. Kang, T.W. Kim, Mechanical behavior and microstructural evolution of commercially pure titanium in enhanced multi-pass equal channel angular pressing and cold extrusion, Mater. Des. 31 (2010) S54-S60.
[15] F. Zhiguo, J. Hong, S. Xiaogang, S. Jie, Z. Xiaoning, C. Xie, Microstructures and mechanical deformation behaviors of ultrane-grained commercial pure (Grade 3) Ti processed by two-step severe plastic deformation, Mater. Sci. Eng. 527 (2009)
[16] J. Hong, F. Zhiguo, C. Xie, 3D Finite element simulation of deformation behavior of CP-Ti and working load during multi-pass equal channel angular extrusion, Mater. Sci. Eng. 485 (2008) 409-414.
[17] J. Hong, F. Zhiguo, C. Xie, Finite element analysis of temperature rise in CP-Ti during equal channel angular extrusion, Mater. Sci. Eng. 513 (2009) 109-114.
[18] A.Yu. Vinogradov, V.V. Stolyarov, S. Hashimoto, R.Z. Valiev, Cyclic behavior of ultrane-grain titanium produced by severe plastic deformation, Mater. Sci. Eng. 318 (2001) 163-173.
[19] A.V. Nagasekhar, U. Chakkingal, P. Venugopal, Candidature of equal channel angular pressing for processing of tubular commercial purity-titanium, J. Mater. Process. Tech. 173(1) (2006) 53-60.
[20] J. Nemati, G.H. Majzoobi, S. Sulaiman, B.T.H.T. Baharudin, M.A.A. Hanim, Finite element and metallurgical study of properties of deformed pure copper by ECAE at various strain rates, J. Mech. Eng. Sci. 228(9) (2014) 1461-1473.
[21] J. Nemati, G.H. Majzoobi, S. Sulaiman, B.T.H.T. Baharudin, M.A. Azmah Hanim, Improvements in the microstructure and fatigue behavior of pure copper using equal channel angular extrusion, Int. J. Miner. Metall. Mater. 21(6) (2014) 569-576.
[22] W. Zhang, L. Jiang, N. Li, W. Yuhua, Improvement of shape memory effect in an Fe-Mn-Si-Cr-Ni alloy fabricated by equal channel angular pressing, J. Mater. Process. Tech. 208 (2008) 130-134.
[23] A.S.M. Agena, A study of ow characteristics of nanostructured Al-6082 alloy produced by ECAP under upsetting test, J. Mater. Process. Tech. 209 (2009) 856-863.
[24] J. Nemati, G.H. Majzoobi, S. Sulaiman, B.T.H.T. Baharudin, M.A. Azmah Hanim, Improvements in the microstructure and fatigue behavior of pure copper using equal channel angular extrusion, Int. J. Miner. Metall. Mater. 22(4) (2015) 395-404.
[25] S. Sulaiman, J. Nemati, M. Hani Mizhir, B.T.H.T. Baharudin, G.H. Majzoobi, M.A.A. Hanim, Experimental Study of IMPact Strength of Al-6063 Alloy Processed by Equal Channel Angular Extrusion, Adv. Mater. Res. 911 (2014) 158-162.