Investigations on Hot Tearing Behavior of Mg-7Zn-xCu-0.6Zr Alloys

doi:10.11900/0412.1961.2016.00476

Acta Metall Sin

2017, Vol. 53

Issue (7): 851-860 DOI: 10.11900/0412.1961.2016.00476

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Investigations on Hot Tearing Behavior of Mg-7Zn-xCu-0.6Zr Alloys

Ye ZHOU,Pingli MAO(

),Zhi WANG,Zheng LIU,Feng WANG

School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China

Cite this article:

Ye ZHOU,Pingli MAO,Zhi WANG,Zheng LIU,Feng WANG. Investigations on Hot Tearing Behavior of Mg-7Zn-xCu-0.6Zr Alloys. Acta Metall Sin, 2017, 53(7): 851-860.

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Abstract

As one of the highest temperature magnesium alloys, Mg-Zn-Cu ternary alloys are draw much attention in recent years. However, the previous investigations were mainly focused on their microstructure and mechanical properties. The investigations on their solidification and hot tearing behaviors are barely discussed. In order to improve the industrial applications of Mg-Zn-Cu alloy, it is necessary to better understand the solidification pathways, phase constituent and hot tearing susceptibility (HTS) of these alloys. In this work, the effect of Cu additions on the hot tearing behaviors of Mg-7Zn-xCu-0.6Zr (x=0, 1, 2, 3) alloys was studied using with T type hot tearing mold. The microstructure and the morphology of cracking zone of Mg-7Zn-xCu-0.6Zr (x=0, 1, 2, 3) alloys were observed by XRD and SEM, respectively. The hot cracking susceptibility of Mg-7Zn-xCu-0.6Zr (x=0, 1, 2, 3) alloys were characterized by the measurement of crack volume. The experimental results show that the grain sizes of Mg-7Zn-0.6Zr alloys were refined by addition of Cu element. Meanwhile, the amount of eutectic phase was increased with increasing the Cu content and the separated dendritic was refilled by the eutectic phase. Hot tearing susceptibility of Mg-7Zn-0.6Zr was decreased with increasing of Cu content. The Mg-7Zn-0.6Zr and Mg-7Zn-1Cu-0.6Zr alloys were completely broken. The hot cracks of Mg-7Zn-xCu-0.6Zr (x=0, 1, 2, 3) alloys were formed by liquid film, solidification shrinkage and interdendritic bridge.

Key words: Mg-Zn-Cu-Zr alloy hot tearing behavior solidification curve microstructure

Received: 25 October 2016

Fund: Supported by National Natural Science Foundation of China (Nos.51504153 and 51571145) and General Project of scientific research of the Education Department of Liaoning Province (No.L2015397)

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	Ye ZHOU
	Pingli MAO
	Zhi WANG
	Zheng LIU
	Feng WANG

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https://www.ams.org.cn/EN/10.11900/0412.1961.2016.00476 OR https://www.ams.org.cn/EN/Y2017/V53/I7/851

Fig.1 Schematics of experimental setup

(a) whole setup (b) thermocouple position for detecting onset of hot cracking during casting (unit: mm)

Fig.2 Definition schematic diagram of dendritic coherence temperature and dendritic coherence solid fraction (Inset shows the high magnified curves. T_c—melt center temperature, T_e—melt edge temperature, ΔT—melt center and edge temperature difference)

Table 1 Dendritic coherence temperature (T_coh) and dendritic coherence solid fraction (f_s^coh) of Mg-7Zn-xCu-0.6Zr (x=0, 1, 2, 3) alloys

Fig.3 Thermal analysis curves of Mg-7Zn-xCu-0.6Zr (x=0, 1, 2, 3) alloys (L—liquidus, S—solidus, T—solidification temperature, t—solidification time)

(a) x=0 (b) x=1 (c) x=2 (d) x=3

Fig.4 XRD spectra of Mg-7Zn-xCu-0.6Zr (x=0, 1, 2, 3) alloys

Table 2 Thermal analysis results for the characteristic temperatures for Mg-7Zn-xCu-0.6Zr (x=0, 1, 2, 3) alloys (℃)

Fig.5 Hot cracks of Mg-7Zn-xCu-0.6Zr (x=0,1,2,3) alloys under different initial mold temperatures

(a) x=0, 200 ℃ (b) x=1, 200 ℃ (c) x=2, 200 ℃ (d) x=3, 200 ℃ (e) x=0, 250 ℃ (f) x =1, 250 ℃

Fig.6 Contraction force and temperature as function of time in Mg-7Zn-xCu-0.6Zr alloy with x=0 (a), x=1 (b), x=2 (c) and x=3 (d) (f_s—solid fraction)

Fig.7 OM images of Mg-7Zn-xCu-0.6Zr alloys with x=0 (a), x=1 (b), x=2 (c) and x=3 (d)

Fig.8 Grain sizes of Mg-7Zn-xCu-0.6Zr (x=0, 1, 2, 3) alloys

Fig.9 SEM images of the hot tearing fracture surface of Mg-7Zn-xCu-0.6Zr alloy with x=0 (a), x=1 (b), x=2 (c) and x=3 (d)

[1]	Mao P L, Liu Z X, Liu Z, et al.Effect of grain size on adiabatic shear sensitivity of AZ31 magnesium alloy[J]. J Shenyang Univ. Technol., 2015, 37: 494
[1]	(毛萍莉, 刘遵鑫, 刘正等. 晶粒大小对AZ31镁合金绝热剪切敏感性的影响[J]. 沈阳工业大学学报, 2015, 37: 494)
[2]	Liu Z, Wang Y, Wang G Z, et al.Developing trends of research and application of magnesium alloys[J]. Chin. J Mater. Res., 2000, 14: 449
[2]	(刘正, 王越, 王中光等. 镁基轻质材料的研究与应用[J]. 材料研究学报, 2000, 14: 449)
[3]	Mordike B L, Ebert T.Magnesium: properties-applications-potential[J]. Mater. Sci. Eng., 2001, A302: 37
[4]	Dahle A K, Lee Y C, Nave M D, et al.Development of the as-cast microstructure in magnesium-aluminium alloys[J]. J. Light Met., 2001, 1: 61
[5]	Huang Z H, Liang S M, Chen R S, et al.Solidification pathways and constituent phases of Mg-Zn-Y-Zr alloys[J]. J. Alloys Compd., 2009, 468: 170
[6]	Wang Y S, Sun B D, Wang Q D, et al.An understanding of the hot tearing mechanism in AZ91 magnesium alloy[J]. Mater. Lett., 2002, 53: 35
[7]	Ding H, Fu H Z, Liu Z Y, et al.Compensation of solidification contraction and hot cracking tendency of alloy[J]. Acta Metall. Sin., 1997, 33: 921
[7]	(丁浩, 傅恒志, 刘忠元等. 凝固收缩补偿与合金的热裂倾向[J]. 金属学报, 1997, 33: 921)
[8]	Monroe C, Beckermann C. Development of a hot tear indicator for steel castings [J]. Mater. Sci. Eng., 2005, A413-414: 30
[9]	Mathier V, Drezet J M, Rappaz M.Two-phase modelling of hot tearing in aluminium alloys using a semi-coupled approach[J]. Modell. Simul. Mater. Sci. Eng., 2007, 15: 121
[10]	Xu R F.Study on hot tearing formation in hypoeutectic Al-Si alloys [D]. Ji'nan: Shandong University, 2014
[10]	(许荣福. 亚共晶Al-Si合金热裂形成过程的研究 [D]. 济南: 山东大学, 2014)
[11]	Huang Y G, Wu G H, Hou Z Q, et al.Hot crack susceptibility of Mg-Gd-Y-Zr magnesium alloy[J]. Spec. Cast. Nonferrous Alloys, 2009, 29: 181
[11]	(黄玉光, 吴国华, 侯正全等. Mg-Gd-Y-Zr合金的热裂性能[J]. 特种铸造及有色合金, 2009, 29: 181)
[12]	Eskin D G, Suyitno, Katgerman L.Mechanical properties in the semi-solid state and hot tearing of aluminium alloys[J]. Prog. Mater. Sci., 2004, 49: 629
[13]	Novikov I I, Grushko O E.Hot cracking susceptibility of Al-Cu-Li and Al-Cu-Li-Mn alloys[J]. Mater. Sci. Technol., 1995, 11: 926
[14]	Ding H, Fu H Z, Luo S Z, et al.Influence of composition on hot cracking tendency of directionally solidified Al-Cu alloy[J]. Acta Metall. Sin., 1995, 31: 376
[14]	(丁浩, 傅恒志, 罗栓柱等. 化学成分对定向凝固Al-Cu合金热裂倾向的影响[J]. 金属学报, 1995, 31: 376)
[15]	Cao G, Kou S.Hot cracking of binary Mg-Al alloy castings[J]. Mater. Sci. Eng., 2006, A417: 230
[16]	Cao G, Kou S.Hot tearing of ternary Mg-Al-Ca alloy castings[J]. Metall. Mater. Trans., 2006, 37A: 3647
[17]	Cao G, Haygood I, Kou S.Onset of hot tearing in ternary Mg-Al-Sr alloy castings[J]. Metall. Mater. Trans., 2010, 41A: 2139
[18]	Zhen Z S, Hort N, Utke O, et al.Investigations on hot tearing of Mg-Al binary alloys by using a new quantitative method [A]. Magnesium Technology[M]. San Francisco, California, USA: Wiley, 2009: 105
[19]	Zhou L.Investigations on hot tearing susceptibility and mechanism of Mg-Zn-(Al) alloys [D]. Shenyang: Shenyang University of Technology, 2011
[19]	(周乐. Mg-Zn-(Al)系合金热裂敏感性及其微观机理研究 [D]. 沈阳: 沈阳工业大学, 2011)
[20]	Zhang S B.Investigations on testing methods and hot tearing susceptibility of Mg-Zn-Y alloys [D]. Shenyang: Shenyang University of Technology, 2014
[20]	(张斯博. Mg-Zn-Y合金热裂行为测试研究 [D]. 沈阳: 沈阳工业大学, 2014)
[21]	Unsworth W.New magnesium alloy for automobile applications[J]. Light Met. Age, 1987, 45: 10
[22]	Chen X Q, Liu J W, Luo C P.Research status and development trend of Mg-Zn alloys with high strength[J]. Mater. Rev., 2008, 22(5): 58
[22]	(陈晓强, 刘江文, 罗承萍. 高强度Mg-Zn系合金的研究现状与发展趋势[J]. 材料导报, 2008, 22(5): 58)
[23]	Li X.Precipitation behavior of cast ZC62 magnesium alloy [D]. Guangzhou: South China University of Technology, 2006
[23]	(李萧. 铸造ZC62镁合金显微组织与力学性能的研究 [D]. 广州: 华南理工大学, 2006)
[24]	Li X, Liu J W, Luo C P.Precipitation behavior of cast ZC62 magnesium alloy[J]. Acta Metall. Sin., 2006, 42: 733
[24]	(李萧, 刘江文, 罗承萍. 铸造ZC62镁合金的时效行为[J]. 金属学报, 2006, 42: 733)
[25]	Zhao C.Study on microstructures and properties of Mg-Zn-Cu-Ce alloys [D]. Chongqing: Chongqing University, 2012
[25]	(赵冲. Mg-Zn-Cu-Ce合金组织与性能研究 [D]. 重庆: 重庆大学, 2012)
[26]	Zhu H M.A study of the aging behavior, microstructures and mechanical properties of cast Mg-6Zn-xCu-0.6Zr (x=0-2.0) alloys [D]. Guangzhou: South China University of Technology, 2011
[26]	(朱红梅. Mg-6Zn-xCu-0.6Zr (x=0-2.0)铸造镁合金的时效行为、显微组织及力学性能研究 [D]. 广州: 华南理工大学, 2011)
[27]	Unsworth W.New magnesium alloy for automobile applications[J]. Light Met. Age, 1987, 8: 10
[28]	Shankar S, Riddle Y W, Makhlouf M M.Nucleation mechanism of the eutectic phases in aluminum-silicon hypoeutectic alloys[J]. Acta Mater., 2004, 52: 4447
[29]	Huang Z H, Zhao H, Lv L Q, et al.Thermal analysis and its application[J]. Hot Working Technol., 2010, 39(7): 19
[29]	(黄张洪, 赵惠, 吕利强等. 热分析技术及其应用[J]. 热加工工艺, 2010, 39(7): 19)
[30]	Liu Z, Zhang S B, Mao P L, et al.Effects of Y on hot tearing formation mechanism of Mg-Zn-Y-Zr alloys[J]. Mater. Sci. Technol., 2014, 30: 1214
[31]	Dahle A K, Stjohn D H.Rheological behaviour of the mushy zone and its effect on the formation of casting defects during solidification[J]. Acta Mater., 1998, 47: 31
[32]	Hou D H.Solidification path, dendrite growth restriction factor and grain size of cast Mg-Al-Zn alloy [D]. Dalian: Dalian University of Technology, 2015
[32]	(侯丹辉. 铸造Mg-Al-Zn系合金的凝固路径、枝晶生长约束因子及晶粒尺寸 [D]. 大连: 大连理工大学, 2015)
[33]	Zheng L J, Wang C H, Hou L Z, et al.Effect of equal-channel angular pressing on microstructure and mechanical properties of AM50 magnesium alloy[J]. Chin. J. Rare Met., 2005, 29: 615
[33]	(郑立静, 王春晖, 侯亮卓等. 热加工对铸造AM50镁合金显微结构和力学性能的影响[J]. 稀有金属, 2005, 29: 615)
[34]	Liu C F.Research on microstructures and mechanical properties of Mg-Zn-Cu alloys [D]. Shenyang: Northeastern University, 2013
[34]	(刘长富. Mg-Zn-Cu合金显微组织和力学性能研究 [D]. 沈阳: 东北大学, 2013)
[35]	Wang Z, Song J F, Huang Y D, et al.An investigation on hot tearing of Mg-4.5Zn-(0.5Zr) alloys with Y additions[J]. Metall. Mater. Trans., 2015, 46A: 2108

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