Gradual shear band cracking and apparent softening of metallic glass under low temperature compression

IMR OpenIR

	Gradual shear band cracking and apparent softening of metallic glass under low temperature compression
	Wu, S. J.; Wang, X. D.; Qu, R. T.; Zhu, Z. W.; Liu, Z. Q.; Zhang, H. F.; Zhang, Z. F.; Qu, RT; Zhang, ZF (reprint author), Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Peoples R China.
	2017-08-01
发表期刊	INTERMETALLICS
ISSN	0966-9795
卷号	87 页码:45-54
摘要	Metallic glasses (MGs) usually exhibit synchronously enhanced plasticity and strength with decreasing the testing temperature. Although great efforts have been made, why MGs show better plasticity at low temperature remains unclear. In this work, the shear band cracking and fracture mechanism of a relatively brittle TiZr-based MG was investigated through methods of low temperature compression and 3D X-ray tomography. Pronounced apparent softening and profuse internal shear-band cracks were observed along with the improved plasticity, enhanced yield strength, decreased average softening rate, and reduced area of vein pattern as decreasing the testing temperature. Moreover, the fracture features can be correlated well with the compressive properties; and the true rupture stress that is carried by the still-bonded part of major shear band was found to be very close to the yield strength, demonstrating that the apparent softening should mainly originate from the cracking rather than dilation of shear band. The decreased softening rate can be fitted by a diffusion model, implying reduced atomic mobility and increased cracking resistance. Consequently, the improved plasticity of TiZr-MG at low temperature was attributed to the suppression of instant fracture and the enhanced resistance to shear band cracking, rather than the change of shear band density.; Metallic glasses (MGs) usually exhibit synchronously enhanced plasticity and strength with decreasing the testing temperature. Although great efforts have been made, why MGs show better plasticity at low temperature remains unclear. In this work, the shear band cracking and fracture mechanism of a relatively brittle TiZr-based MG was investigated through methods of low temperature compression and 3D X-ray tomography. Pronounced apparent softening and profuse internal shear-band cracks were observed along with the improved plasticity, enhanced yield strength, decreased average softening rate, and reduced area of vein pattern as decreasing the testing temperature. Moreover, the fracture features can be correlated well with the compressive properties; and the true rupture stress that is carried by the still-bonded part of major shear band was found to be very close to the yield strength, demonstrating that the apparent softening should mainly originate from the cracking rather than dilation of shear band. The decreased softening rate can be fitted by a diffusion model, implying reduced atomic mobility and increased cracking resistance. Consequently, the improved plasticity of TiZr-MG at low temperature was attributed to the suppression of instant fracture and the enhanced resistance to shear band cracking, rather than the change of shear band density.
部门归属	[wu, s. j. ; wang, x. d. ; qu, r. t. ; zhu, z. w. ; liu, z. q. ; zhang, h. f. ; zhang, z. f.] chinese acad sci, inst met res, shenyang natl lab mat sci, shenyang 110016, peoples r china ; [wu, s. j.] univ sci & technol china, sch mat sci & engn, hefei 230026, peoples r china
关键词	Metallic Glass Shear Band Fracture Mechanism Compression Low Temperature
学科领域	Chemistry, Physical ; Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering
资助者	National Natural Science Foundation of China (NSFC) [51331007, 51301174, 51434008 (U1435204), 51501190]
收录类别	SCI
语种	英语
WOS记录号	WOS:000401737400008
引用统计	被引频次：21[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/78034
专题	中国科学院金属研究所
通讯作者	Qu, RT; Zhang, ZF (reprint author), Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Peoples R China.
推荐引用方式 GB/T 7714	Wu, S. J.,Wang, X. D.,Qu, R. T.,et al. Gradual shear band cracking and apparent softening of metallic glass under low temperature compression[J]. INTERMETALLICS,2017,87:45-54.
APA	Wu, S. J..,Wang, X. D..,Qu, R. T..,Zhu, Z. W..,Liu, Z. Q..,...&Zhang, ZF .(2017).Gradual shear band cracking and apparent softening of metallic glass under low temperature compression.INTERMETALLICS,87,45-54.
MLA	Wu, S. J.,et al."Gradual shear band cracking and apparent softening of metallic glass under low temperature compression".INTERMETALLICS 87(2017):45-54.