Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching-Partitioning-Tempering Steels

doi:10.1007/s40195-017-0683-3

Abstract

Abstract:

The orientation relationships (ORs) between the martensite and the retained austenite in low- and medium-carbon steels after quenching-partitioning-tempering process were studied in this work. The ORs in the studied steels are identified by selected-area electron diffraction (SAED) as either K-S or N-W ORs. Meanwhile, the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto. The simulated K-S and N-W ORs in the low-index directions generally do not well coincide with the experimental pole figure, which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions. However, the simulated results coincide well with experimental pole figures in the high-index directions {123}_bcc. A modified method with simplicity based on Miyamoto’s work was proposed. The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’ method, that is, the OR is near K-S OR for the low-carbon Q-P-T steel, and with the increase of carbon content, the OR is closer to N-W OR in medium-carbon Q-P-T steel.

Key words: Martensite, steels, Martensite, transformation, Retained, austenite, Orientation, relationship, Electron, backscattered, diffraction

Ke Zhang, Ping Liu, Wei Li, Feng-Cang Ma, Yong-Hua Rong. Quantitative Analysis of the Crystallographic Orientation Relationship Between the Martensite and Austenite in Quenching-Partitioning-Tempering Steels[J]. Acta Metallurgica Sinica (English Letters), 2018, 31(6): 659-667.

Figures/Tables 8

Table 1 Chemical compositions of experimental Q-P-T steels (wt%)

Sample	C	Mn	Si	Nb	Ac₃ (°C)	M _s (°C)	M _f (°C)
Low-carbon steel	0.19	1.52	1.57	0.029	911 ± 5	395 ± 5	171 ± 3
Medium-carbon steel	0.42	1.46	1.58	0.028	797 ± 5	289 ± 5	84 ± 3

Fig. 1 TEM images show the martensite and retained austenite in the Q-P-T samples: a bright field image of the retained austenite in low-carbon steel; b dark field image of the retained austenite in low-carbon steel; c SAED pattern from low-carbon steel; d bright field image of the medium-carbon steel; e dark field image of the retained austenite of the medium-carbon steel; f SAED pattern from the medium-carbon steel

Fig. 2 Orientation imaging maps of low-carbon a, b and medium-carbon c, d steels after Q-P-T process. Martensite and retained austenite are simultaneously shown in a, c, while only retained austenite is shown in b, d as red. The white line indicates the prior austenite grain boundaries

Fig. 3 a OIM of low-carbon steel corresponds to the area surrounded by the white line in Fig. 2a. b Experimental {001}bcc pole figure of lath martensite and retained austenite corresponds to a. c K-S, d N-W ORs simulated from experimental {001}bcc pole figure. The symbols and numbers represent the variant numbers, and the symbol A represents retained austenite

Fig. 4 a Experimental {001}bcc pole figure of lath martensite and retained austenite corresponds to the area surrounded by the white line in Fig. 2c. b K-S, c N-W ORs simulated from {001}bcc pole figure. The symbol A in a represents the retained austenite

Fig. 5 Experimental {123}bcc pole figures of the lath martensite and retained austenite in low-carbon a-c and medium-carbon d-f steels after Q-P-T process. a, d Are patterns measured, while b, e K-S, c, f N-W ORs simulated from {123}bccpole figures, respectively

Fig. 6 Research area (in black rectangle) of low-carbon steel a and medium-carbon steel b after Q-P-T process corresponds to the partial magnification of Fig. 2a, c, respectively. The symbol A represents the retained austenite

Table 2 Euler angle of retained austenite obtained by simulation and EBSD measurement

Sample	Euler angle
Sample	\(\varphi_{1}\)	\(\varPhi\)	\(\varphi_{2}\)
Low-carbon Q-P-T steel (simulation)	216.55	12.85	9.40
Low-carbon Q-P-T steel (measurement)	217.39	12.79	9.42
Medium-carbon Q-P-T steel (simulation)	79.80	45.60	40.30
Medium-carbon Q-P-T steel (measurement)	79.71	45.59	40.38

References

[1]	T.Y. Hsu, Mater. Sci. Forum 561-565, 2283(2007)
[2]	J.G. Speer, D.K. Matlock, B.C.De Cooman, J.G. Schroth, Acta Mater. 51, 2611(2003)
[3]	X.D. Wang, B.X. Huang, Y.H. Rong, L. Wang, Mater. Sci. Eng., A 438, 300 (2006)
[4]	A.J. Clarke, J.G. Speer, M.K. Miller, R.E. Hackenberg, Acta Mater. 56, 16(2008)
[5]	N. Zhong, X.D. Wang, L. Wang, Y.H. Rong, Mater. Sci. Eng., A 506, 111 (2009)
[6]	X.D. Wang, N. Zhong, Y.H. Rong, T.Y. Hsu, L. Wang, J. Mater. Res. 24, 260(2009)
[7]	K. Zhang, P. Liu, W. Li, Z.H. Guo, Y.H. Rong, Mater. Sci. Eng., A 619, 205 (2014)
[8]	S. Morito, H. Tanaka, R. Konishi, T. Furuhara, T. Maki, Acta Mater. 51, 1789(2003)
[9]	C.P. Luo, J. Liu, Mater. Sci. Eng., A 438, 149 (2006)
[10]	H. Kitahare, R. Ueji, N. Tsuji, Y. Minamino, Acta Mater. 54, 1279(2006)
[11]	S. Morito, X. Huang, T. Furuhara, T. Maki, N. Hansen, Acta Mater. 54, 5323(2006)
[12]	S. Morito, H. Yoshida, T. Maki, X. Huang, Mater. Sci. Eng., A 438, 237 (2006)
[13]	G. Miyamoto, N. Iwata, N. Takayama, T. Furuhara, Acta Mater. 60, 1139(2012)
[14]	A. Stormvinter, G. Miyamoto, T. Furuhara, P. Hedstrom, A. Borgenstam, Acta Mater. 60, 7265(2012)
[15]	G. Miyamoto, N. Iwata, N. Takayama, T. Furuhara, J. Alloys Compd. 577, 528(2013)
[16]	F. Maresca, V.G. Kouznetsova, M.G.D.Geers, J. Mech. Phys. Solids 73, 69 (2014)
[17]	P.M. Kelly, A. Jostsons, R.G. Blake, Acta Metall.Mater. 38, 1075(1990)
[18]	M.X. Zhang, P.M. Kelly, Mater. Sci. Eng., A 438, 272 (2006)
[19]	P.P. Suikkanen, C. Cayron, A.J.De Ardo, P. Karjalainen, J. Mater. Sci. Technol. 27, 920(2011)
[20]	G. Nolze, Cryst. Res. Technol. 41, 72(2006)
[21]	G. Miyamoto, N. Takayama, T. Furuhara, Scr. Mater. 60, 1113(2009)
[22]	Y. Wang, K. Zhang, Z.H. Guo, N.L. Chen, Y.H. Rong, Acta Metall.Sin. 48, 641(2012)
[23]	K. Zhang, M.H. Zhang, Z.H. Guo, N.L. Chen, Y.H. Rong, Mater. Sci. Eng., A 528, 8486 (2011)
[24]	S.W. Qin, Y. Liu, Q.G. Hao, Y. Wang, N.L. Chen, X.W. Zuo, Y.H. Rong, Mater. Sci. Eng., A 663, 151 (2016)
[25]	M. Santofimia, L. Zhao, R. Petrov, J. Sietsma, Mater. Charact. 59, 1758(2008)
[26]	G. Thomas, J.G. Speer, D.K. Matlock, J. Michael, Microsc. Microanal. 17, 368(2011)
[27]	F. Barcelo, Y. De Carlan, J.L. Be′chade, B. Fournier, Phase Transit. 82, 808(2009)