Dislocation velocities in Ni3Al single crystals

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	Dislocation velocities in Ni3Al single crystals
	C. B. Jiang; S. Patu; Q. Z. Lei; C. X. Shi
	1998
发表期刊	Philosophical Magazine Letters
ISSN	0950-0839
卷号	78 期号:1 页码:40916
摘要	The average velocities of dislocations moving on octahedral and cube planes in Ni3Al single crystals have been measured as a function of the resolved shear Stress (RSS) in the temperature range from 293 to 1133K by the etch-pit technique. The RSS dependence of the velocities can be expressed by an equation of the form upsilon = upsilon(0)(tau/tau(0))(m) in all cases. Some of the parameters associated with the dislocation mobility are deduced from the experimental data. For the octahedral slip, the exponent m lies between 20 and 31 and the activation area A* = (81-99)b(2). For cube slip, m = 12-16 and A* = (56-84)b(2). Three temperature domains have been defined where different glide systems operate. In the first domain the dislocation can move only on the octahedral plane, in the second domain it can move on both octahedral and cube planes, and in the third domain it can move only on the cube plane. It is found that the velocity of dislocations moving on the octahedral plane exhibits anomalous behaviour, consisting of a positive temperature dependence of the RSS as required for a constant dislocation velocity and a tension-compression velocity asymmetry. No obvious anomalous velocity behaviour for the cube glide system was observed. All these results suggest that positive temperature dependence of the critical resolved shear stress and the tension-compression flow asymmetry in L1(2) Ni3Al can be directly related to the behaviour of individual dislocation velocities.
部门归属	chinese acad sci, inst met res, state key lab fatigue & fracture mat, shenyang 110015, peoples r china.;patu, s (reprint author), chinese acad sci, inst met res, state key lab fatigue & fracture mat, wenhua rd 72, shenyang 110015, peoples r china;patu@imr.ac.cn
关键词	Ordered Alloys
URL	查看原文
WOS记录号	WOS:000074568200001
引用统计	被引频次：15[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/321006/37686
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	C. B. Jiang,S. Patu,Q. Z. Lei,et al. Dislocation velocities in Ni3Al single crystals[J]. Philosophical Magazine Letters,1998,78(1):40916.
APA	C. B. Jiang,S. Patu,Q. Z. Lei,&C. X. Shi.(1998).Dislocation velocities in Ni3Al single crystals.Philosophical Magazine Letters,78(1),40916.
MLA	C. B. Jiang,et al."Dislocation velocities in Ni3Al single crystals".Philosophical Magazine Letters 78.1(1998):40916.