EFFECT OF FINISH COOLING TEMPERATURE ON MICROSTRUCTURE AND LOW TEMPERATURE TOUGHNESS OF Mn-SERIES ULTRA-LOW CARBON HIGH STRENGTH LOW ALLOYED STEEL

doi:10.11900/0412.1961.2014.00329

Acta Metall Sin

2015, Vol. 51

Issue (1): 21-30 DOI: 10.11900/0412.1961.2014.00329

Current Issue | Archive | Adv Search

EFFECT OF FINISH COOLING TEMPERATURE ON MICROSTRUCTURE AND LOW TEMPERATURE TOUGHNESS OF Mn-SERIES ULTRA-LOW CARBON HIGH STRENGTH LOW ALLOYED STEEL

GAO Guhui¹, GUI Xiaolu¹, AN Baifeng¹, TAN Zhunli¹, BAI Bingzhe²(

), WENG Yuqing²

1 Material Science and Engineering Research Center, School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044
2 Key Laboratory of Advanced Material, School of Materials Science and Engineering, Tsinghua University, Beijing 100084

Cite this article:

GAO Guhui, GUI Xiaolu, AN Baifeng, TAN Zhunli, BAI Bingzhe, WENG Yuqing. EFFECT OF FINISH COOLING TEMPERATURE ON MICROSTRUCTURE AND LOW TEMPERATURE TOUGHNESS OF Mn-SERIES ULTRA-LOW CARBON HIGH STRENGTH LOW ALLOYED STEEL. Acta Metall Sin, 2015, 51(1): 21-30.

Download:

HTML

PDF(9888KB)
Export: BibTeX | EndNote (RIS)

Abstract

Recently, the steel plates used in the ship, pipeline and bridge generally required not only high strength but also excellent low temperature toughness. As a competitive candidate, the ultra-low carbon high strength low alloyed (HSLA) steel has been developed widely. The low temperature toughness depends on the microstructure of the steels. Therefore, the relationship of low temperature toughness and microstructure should be studied in detail. In the present work, the steel plates with 25 mm thickness after hot rolling were immediately water quenched to 550, 450 and 350 ℃(finish cooling temperature), respectively, and subsequently air cooled to room temperature. The effect of finish cooling temperature on the microstructure and low temperature toughness of Mn-series ultra-low carbon HSLA steel was investigated by SEM, TEM and crystallographic analysis. The results show that the granular bainite, lath bainite and martensite were obtained with finish cooling temperatures decreasing. There are three blocks with different orientations in a single packet for lath bainite microstructure in the sample with finish cooling temperature of 450 ℃, leading to the refinement of effective grain size and large amount of high-angle grain boundaries. Electron backscattered diffraction analyses of the cleavage crack path show that the bainite block boundaries can strongly hinder fracture propagation, and thus the refinement of bainite blocks can improve the low temperature toughness of Mn-series ultra-low carbon HSLA steel. Finally, the yield strength of 775 MPa and ductile-brittle transition temperature of -55 ℃can be achieved when the finish cooling temperature is 450 ℃.

Key words: ultra-low carbon HSLA steel bainite microstructure low temperature toughness block crystallographic feature

ZTFLH:

TG146.2

Fund: Supported by Fundamental Research Funds for the Central Universities (No.2014JBM101

	Service

	E-mail this article
	Add to citation manager
	E-mail Alert
	RSS
	（）
	Articles by authors
	Guhui GAO
	Xiaolu GUI
	Baifeng AN
	Zhunli TAN
	Bingzhe BAI
	Yuqing WENG

URL:

https://www.ams.org.cn/EN/10.11900/0412.1961.2014.00329 OR https://www.ams.org.cn/EN/Y2015/V51/I1/21

Fig.1 Ductile-brittle transition curves of the ULC-HSLA steel under different finish cooling temperatures

Table 1 Tensile properties of the ultra-low carbon high strength low alloyed (ULC-HSLA) steel under different finish cooling temperatures

Fig.2 SEM (a, c, e) and TEM (b, d, f) images of the ULC-HSLA steel with the finish cooling temperatures of 550 ℃ (a, b), 450 ℃ (c, d) and 350 ℃ (e, f) (M/A—martensite/austenite island, LB—lath bainite, M—martensite)

Table 2 Twenty-four variants in K-S relationship^[15]

Fig.3 EBSD analysis of the sample with finish cooling temperature of 550 ℃

Fig.4 Boundary map of the sample with finish cooling temperature of 550 ℃(The white, yellow, blue and red lines indicate the prior austenite grain boundaries and the boundaries with misorientations of 2°~10°, 10°~15° and higher than 15°, respectively) (a), point-to-origin A misorientation of A-B line (b) and point-to-point misorientation of A-B line (c)

Fig.5 EBSD analysis of the sample with finish cooling temperature of 450 ℃

Fig.6 Boundary map of the sample with finish cooling temperature of 450 ℃(The white, yellow, blue and red lines indicate the prior austenite grain boundaries and the boundaries with misorientations of 2°~10°, 10°~15° and higher than 15°, respectively) (a), point-to-origin A misorientation of A-B line (b) and point-to-point misorientation of A-B line (c)

Fig.7 SEM image and EBSD analysis of the sample with finish cooling temperature of 450 ℃

Fig.8 EBSD analysis of the sample with finish cooling temperature of 350 ℃

Fig.9 SEM images of cross-sectional area beneath cleavage fracture surface of Charpy impact specimen fractured at -80 ℃for the samples with finish cooling temperatures of 550 ℃(a) and 350 ℃(b) (AGB—prior austenite grain boundary)

Fig.10 SEM image (a) and corresponding orientation image obtained by EBSD analysis (b) of cross-sectional area beneath cleavage fracture surface of Charpy impact specimen fractured at -80 ℃ for the samples with finish cooling temperature of 450 ℃(The arrows indicate the propagation of cleavage cracks, the misorientations between adjacent zones are 53.03°, 50.06°, 58.30°, 57.8°, 56.02°, 60.00° and 47.40°, respectively)

[1]	Ghosh A, Das S, Chatterjee S, Rao Ramachandra P. Mater Charact, 2006; 56: 59
[2]	Dong H. Sci China Technol Sci, 2012; 55: 1774
[3]	Wang W, Shan Y Y, Yang K. Acta Metall Sin, 2007; 43: 578
	(王伟, 单以银, 杨柯. 金属学报, 2007; 43: 578)
[4]	You Y, Wang X M, Shang C J. Acta Metall Sin, 2012; 48: 1290
	(由洋, 王学敏, 尚成嘉. 金属学报, 2012; 48: 1290)
[5]	Wang X Y, Pan T, Wang H, Su H, Li X Y, Cao X Z. Acta Metall Sin, 2012; 48: 401
	(王小勇, 潘涛, 王华, 苏航, 李向阳, 曹兴忠. 金属学报, 2012; 48: 401)
[6]	Liu D S, Cheng B G, Luo M. Acta Metall Sin, 2011; 47: 1233
	(刘东升, 程丙贵, 罗咪. 金属学报, 2011; 47: 1233)
[7]	Di G B, Liu Z Y, Hao L Q, Liu X H. Mater Mech Eng, 2008; 32(8): 1
	(狄国标, 刘振宇, 郝利强, 刘相华. 机械工程材料, 2008; 32(8): 1)
[8]	Zhou T, Yu H, Hu J, Wang S. Mater Sci Eng, 2014; A615: 436
[9]	Xie Z, Fang Y, Han G, Guo H, Misra R D K, Shang C. Mater Sci Eng, 2014; A618: 112
[10]	Wang C F, Wang M Q, Shi J, Hui W J, Dong H. Scr Mater, 2008; 58: 492
[11]	Schino D A, Guarnschelli C. Mater Lett, 2009; 63: 1968
[12]	Chen J, Tang S, Liu Z Y, Wang G D. Mater Sci Eng, 2013; A559: 241
[13]	Sung H K, Shin S Y, Hwang B, Lee C G, Lee S. Metall Mater Trans, 2013; 44A: 294
[14]	Nie W J, Shang C J, You Y, Zhang X B, Sundaresa S. Acta Metall Sin, 2012; 48: 797
	(聂文金, 尚成嘉, 由洋, 张晓兵, Sundaresa S. 金属学报, 2012; 48: 797)
[15]	Morito S, Tanaka H, Konishi R, Furuhara T, Maki T. Acta Mater, 2003; 51: 1789
[16]	Davis C L, King J E. Metall Mater Trans, 1994; 25A: 563
[17]	Tomita Y, Okabayashi K. Metall Trans, 1986; 17A: 1203
[18]	Naylor J P. Metall Trans, 1979; 10A: 861
[19]	Morito S, Huang X, Furuhara T, Maki T, Hansen N. Acta Mater, 2006; 54: 5323
[20]	Furuhara T, Kawata H, Morito S, Maki T. Mater Sci Eng, 2006; A431: 228
[21]	Kitahara H, Ueji R, Tsuji N, Minamino Y. Acta Mater, 2006; 54: 1279
[22]	Kawata H, Sakamoto K, Moritani T, Morito S, Furuhara T, Maki T. Mater Sci Eng, 2006; A438: 140
[23]	Han S Y, Shin S Y, Seo C H, Lee H, Bae J H, Kim K, Lee S, Kim N J. Metall Mater Trans, 2009; 40A: 1851
[24]	Shin S, Hwang B, Lee S, Kim N J, Ahn S. Mater Sci Eng, 2007; A458: 281
[25]	Pickering F B, Gladman T. ISI Spec Rep, 1961; 81: 10

[1]	Xiuliang MA, Xiaobing HU. High-Resolution Transmission Electron Microscopic Study of Various Borides Precipitated in Superalloys[J]. 金属学报, 2018, 54(11): 1503-1524.
[2]	Liming DONG,Li YANG,Jun DAI,Yu ZHANG,Xuelin WANG,Chengjia SHANG. Effect of Mn, Ni, Mo Contents on Microstructure Transition and Low Temperature Toughness of Weld Metal for K65 Hot Bending Pipe[J]. 金属学报, 2017, 53(6): 657-668.
[3]	Changjun WANG,Jianxiong LIANG,Zhenbao LIU,Zhiyong YANG,Xinjun SUN,Qilong YONG. EFFECT OF METASTABLE AUSTENITE ON MECHANI-CAL PROPERTY AND MECHANISM IN CRYOGENICSTEEL APPLIED IN OCEANEERING[J]. 金属学报, 2016, 52(4): 385-393.
[4]	Zhenjia XIE,Chengjia SHANG,Wenhao ZHOU,Binbin WU. EFFECT OF RETAINED AUSTENITE ON DUCTILITY AND TOUGHNESS OF A LOW ALLOYED MULTI-PHASE STEEL[J]. 金属学报, 2016, 52(2): 224-232.
[5]	ZHANG Hang, XU Qingyan, SUN Changbo, QI Xiang,TANG Ning, LIU Baicheng. SIMULATION AND EXPERIMENTAL STUDIES ON GRAIN SELECTION BEHAVIOR OF SINGLE CRYSTAL SUPERALLOY ：I. Starter Block[J]. 金属学报, 2013, 49(12): 1508-1520.
[6]	LIU Dongsheng CHENG Binggui LUO Mi. MICROSTRUCTURE AND IMPACT FRACTURE BEHAVIOUR OF HAZ OF F460 HEAVY SHIP PLATE WITH HIGH STRENGTH AND TOUGHNESS[J]. 金属学报, 2011, 47(10): 1233-1240.
[7]	YANG Yinhui CHAI Feng YAN Biao SU Hang YANG Caifu. STUDY ON LOW TEMPERATURE TOUGHNESS IMPROVEMENT OF WELDING COARSE GRAIN ZONE OF HULL STEELS BY Ti TREATMENT[J]. 金属学报, 2010, 46(1): 62-70.
[8]	HU Xiaojun (Department of Physicochemistry; University of Science and Technology; Beijing 100083)XUE Xiangxin; DUAN Peining (School of Materials and Metallurgy; Northeastern University; Shenyang 110006)HUANG Xiaoyu(Ironmaking Work; Anshan Iron & Steel Company; Anshan 114021). PERMEATION PROCESS OF MOLTEN IRON IN A SELF-BAKING CARBON BLOCK[J]. 金属学报, 1998, 34(4): 384-387.
[9]	XUE Xiangxin; CHE Yinchang (Northeastern University; Shenyang 110006)DU Yingmin (Institute of Metal Research; Chinese Academy of Sciences; Shenyang 110015)HUANG Hiaoyu (Ironmaking Works; Anshan Iron and Steel Company; Anshan 114012). DETERMINATION OF ENTHALPY AND MASSIC HEAT CAPACITY OF SELF-BAKING CARBON BLOCK[J]. 金属学报, 1996, 32(6): 669-672.
[10]	XUE Xiangxin (Northeastern University; Shenyang 110006); HUANG Xiaoyu (Ironmaking Works; Anshan Iron and Steel Complex; Anshan 114021); DU Yingmin(Institute of Metal Research; Chinese Academy of Sciences; Shenyang 110015); ZHANG Dianyou(Ironmaking Works; Anshan Iron and Steel Complex;Anshan 114021). THERMAL DIFFUSIVITY OF SELF-BAKING CARBON BLOCK WITH DIFFERENT GRAPHITIZATION DEGREES[J]. 金属学报, 1996, 32(11): 1227-1232.

No Suggested Reading articles found!

Viewed

Full text

Abstract

Cited

Shared

Discussed