Enhanced Surface Mechanical Properties and Microstructure Evolution of Commercial Pure Titanium Under Electropulsing-Assisted Ultrasonic Surface Rolling Process

doi:10.1007/s40195-018-0738-0

Abstract

Abstract:

The effects of electropulsing-assisted ultrasonic surface rolling process on surface mechanical properties and microstructure evolution of commercial pure titanium were investigated. It was found that the surface mechanical properties were significantly enhanced compared to traditional ultrasonic surface rolling process (USRP), leading to smaller surface roughness and smoother morphology with fewer cracks and defects. Moreover, surface strengthened layer was remarkably enhanced with deeper severe plastic deformation layer and higher surface hardness. Remarkable enhancements of surface mechanical properties may be related to the gradient refined microstructure, the enhanced severe plastic deformation layer and the accelerated formation of sub-boundaries and twins induced by coupling effects of USRP and electropulsing. The primary intrinsic reasons for these improvements may be attributed to the thermal and athermal effects caused by electropulsing treatment, which would accelerate dislocation mobility and atom diffusion.

Key words: Electropulsing-assisted ultrasonic surface rolling process (EP-USRP), Commercial pure titanium, Roughness, Hardness, Microstructure evolution

Yong-Da Ye, Xiao-Pei Li, Zhi-Yan Sun, Hai-Bo Wang, Guo-Yi Tang. Enhanced Surface Mechanical Properties and Microstructure Evolution of Commercial Pure Titanium Under Electropulsing-Assisted Ultrasonic Surface Rolling Process[J]. Acta Metallurgica Sinica (English Letters), 2018, 31(12): 1272-1280.

Figures/Tables 10

Table 1 Chemical composition of commercial pure titanium (wt%)

Ti	H	O	Fe	C	N
Bal.	0.006	0.12	0.14	0.02	0.03

Fig. 1 Schematic diagram of the EP-USRP process and installation [25]

Table 2 Processing parameters of USRP

Rolling line speed (m/min)	Feeding rate (mm/min)	Frequency (kHz)	Static force (N)	Amplitude (μm)
12.1	13	27	1030	6

Table 3 Processing parameters of EPT

Frequency (Hz)	Root-mean-square current (A/mm²)	Amplitude current (A/mm²)	Duration (μs)	Temperature (°C)
500	0.95	5.0	135	104

Fig. 2 Axial surface roughness and morphology of specimens after USRP and EP-USRP: a and a’ turning; b and b’ USRP; c and c’ EP-USRP

Fig. 3 Cross-sectional micro-hardness distribution within the strengthened layer: a nano-hardness at the depth of 50 μm; b induced by USRP and EP-USRP

Fig. 4 Microstructure of strengthened layer induced by USRP and EP-USRP: a turning; b USRP; c EP-USRP

Fig. 5 Microstructure of plastic deformation layer at top surface and 50 μm below the surface induced by USRP and EP-USRP: a turning at the surface; a’ turning at 50 μm below the surface; b USRP at the surface; b’ USRP at 50 μm below the surface; c EP-USRP at the surface; c’ EP-USRP at 50 μm below the surface

Fig. 6 EBSD maps at 250 μm depth below the surface induced by a USRP; b EP-USRP

Fig. 7 Distribution of twins induced by a USRP; b EP-USRP at 400-500 μm depth below the surface

References

[1]	H. Wang, G. Song, G. Tang, J. Alloys Compd. 681, 146(2016)
[2]	C. Ye, A. Telang, A.S. Gill, S. Suslov, Y. Idell, Z. Kai, J.M.K. Wiezorek， Z. Zhou， D. Qian， S.R. Mannava, Mater. Sci. Eng. A 11-12, 613(2014)
[3]	A. Amanov, I.S. Cho, D.E. Kim, Y.S. Pyun, Surf. Coat. Technol. 21, 207(2012)
[4]	B. Wu, P. Wang, Y.S. Pyoun, J. Zhang, R.I. Murakami, Surf. Coat. Technol. 12, 213(2012)
[5]	X.J. Cao, Y.S. Pyoun, R. Murakami, Appl. Surf. Sci. 21, 256(2010)
[6]	G. Li, S.G. Qu, Y.X. Pan, X.Q. Li, Appl. Surf. Sci. 389, 324(2016)
[7]	T. Liu, H. Wang, G. Tang, G. Song, Mater. Sci. Technol. 12, 33(2017)
[8]	A. Amanov, J.H. Kim, Y.S. Pyun, T. Hirayama, M. Hino, Wear 332-333, 891(2015)
[9]	A. Amanov, Y.S. Pyun, S. Sasaki, Tribol. Int. 4, 72(2014)
[10]	A. Amanov, I.S. Cho, Y.S. Pyun, Appl. Surf. Sci. 388, 185(2016)
[11]	H. Huang, Z. Wang, J. Lu, K. Lu, Acta Mater. 87, 150(2015)
[12]	H. Wang, G. Song, G. Tang, Mater. Sci. Eng. A 662, 456 (2016)
[13]	X. Yang, J. Zhou, X. Ling, Mater. Des. 36, 477(2012)
[14]	A.V. Panin, M.S. Kazachenok, A.I. Kozelskaya, R.R. Hairullin,E.A. Sinyakova, Mater. Sci. Eng. A 647, 43 (2015)
[15]	Y. Jiang, G. Tang, C. Shek, Y. Zhu, Z. Xu, Acta Mater. 16, 57(2009)
[16]	J. Kuang, X. Du, X. Li, Y. Yang, A.A. Luo, G. Tang, Scr. Mater.114, 151(2016)
[17]	X. Li, G. Tang, J. Kuang, X. Li, J. Zhu, Mater. Sci. Eng. A 9,612 (2014)
[18]	Y. Jiang, G. Tang, C. Shek, Y. Zhu, Appl. Phys. A 3, 97 (2009)
[19]	R. Zhu, G. Tang, S. Shi, M. Fu, J. Mater. Process.Technol. 1,213(2013)
[20]	R.S. Qin, A. Rahnama, W.J. Lu, X.F. Zhang, B. Elliottbowman,Mater. Sci. Technol.Lond. 9, 30(2014)
[21]	Q. Xu, L. Guan, Y. Jiang, G. Tang, S. Wang, Mater. Lett. 9, 64(2010)
[22]	V.E. Gromov, Y.F. Ivanov, V.V. Sizov, S.V. Vorob’Ev， S.V. Konovalov, J. Surf. Investig. X-Ray Synchrotron Neutron Tech.1, 7(2013)
[23]	R. Qin, S. Su, J. Mater. Res. 8, 17(2002)
[24]	H. Wang, G. Song, G. Tang, Surf. Coat. Technol. 282, 149(2015)
[25]	Y. Ye, H. Wang, G. Tang, G. Song, J. Mater. Eng. Perform., ed.by R. Asthana (2018 in press)
[26]	X. Liu, H. Zhang, K. Lu, Science 6156, 342 (2013)
[27]	R. Zhu, G. Tang, S. Shi, M. Fu, Mater. Des. 44, 606(2013)
[28]	Y. Jiang, G. Tang, C. Shek, J. Xie, Z. Xu, Z. Zhang, J. Alloys Compd. 536, 94(2012)
[29]	N.R. Tao, Z.B. Wang, W.P. Tong, M.L. Sui, J. Lu, K. Lu, Acta Mater. 18, 50(2002)
[30]	M. Wen, G. Liu, J.F. Gu, W.M. Guan, J. Lu, Appl. Surf. Sci. 12, 255(2009)
[31]	Q. Xu, G. Tang, Y. Jiang, Mater. Sci. Eng. A 13-14, 528(2011)
[32]	Y.H. Zhu, S. To, W.B. Lee, X.M. Liu, Y.B. Jiang, G.Y. Tang,Mater. Sci. Eng. A 1, 501 (2009)
[33]	R.F. Zhu, G.Y. Tang, S.Q. Shi, M.W. Fu, V.E. Gromov, Appl.Phys. A 4, 111 (2013)
[34]	Z. Xu, G. Tang, S. Tian, F. Ding, H. Tian, J. Mater. Process.Technol. 1, 182(2007)
[35]	G. Tang, J. Zhang, M. Zheng, J. Zhang, W. Fang, Q. Li, Mater.Sci. Eng. A 1-2, 281(2000)
[36]	Y.G. Liu, M.Q. Li, Mater. Lett. 185, 488(2016)
[37]	S. Nemat-Nasser, W.G. Guo, J.Y. Cheng, Acta Mater. 13, 47(1999)
[38]	K.Y. Zhu, A. Vassel, F. Brisset, K. Lu, J. Lu, Acta Mater. 14, 52(2004)