摘要The behavior of an extended dislocation near an elliptical blunt crack is investigated. The equilibrium separation between Shockley partials and the critical value of stacking fault energy for the formation of extended dislocations by dissociation reaction as well as the extended dislocation emission criterion are developed. The results show that the equilibrium separation increases as the extended dislocation tends to the blunt crack. If the stacking fault energy is comparable to the critical energy for dissociation in a perfect medium, complete dislocations can dissociate to form extended dislocations near the blunt crack. The critical stress intensity factor (SIF) for extended dislocation emission increases with the stacking fault energy and the curvature radius of the blunt crack tip. Moreover, the critical SIF for extended dislocation emission is far lower than the critical SIF for edge dislocation emission.
Abstract：The behavior of an extended dislocation near an elliptical blunt crack is investigated. The equilibrium separation between Shockley partials and the critical value of stacking fault energy for the formation of extended dislocations by dissociation reaction as well as the extended dislocation emission criterion are developed. The results show that the equilibrium separation increases as the extended dislocation tends to the blunt crack. If the stacking fault energy is comparable to the critical energy for dissociation in a perfect medium, complete dislocations can dissociate to form extended dislocations near the blunt crack. The critical stress intensity factor (SIF) for extended dislocation emission increases with the stacking fault energy and the curvature radius of the blunt crack tip. Moreover, the critical SIF for extended dislocation emission is far lower than the critical SIF for edge dislocation emission.
SONG Hao-Peng;FANG Qi-Hong;LIU You-Wen. Behavior of an Extended Dislocation near an Elliptical Blunt Crack[J]. 中国物理快报, 2009, 26(9): 96102-096102.
SONG Hao-Peng, FANG Qi-Hong, LIU You-Wen. Behavior of an Extended Dislocation near an Elliptical Blunt Crack. Chin. Phys. Lett., 2009, 26(9): 96102-096102.
[1] Klier E P 1951 Trans. Am. Soc. Met. 43 935 [2] Chang L C 1955 J. Mech. Phys. Solids 3 212 [3] Felbeck D K and OEROWAN E 1955 Welding J. 34570 [4] Lin I H and Thomson R 1986 Acta Metall. 34 187 [5] Rice J R and Thomson R 1974 Philos. Mag. 29 73 [6] Lu Z X, Wang X Y, Yu S W and Feng X Q 2007 ActaMechanica Solida Sin. 20 103 [7] Ohr S M, Chang S J and Thomson R 1985 J. Appl. Phys. 57 1839 [8] Huang M X and Li Z H 2004 J. Mech. Phys. Solids 52 1991 [9] Feng X Q and Yu S W 1996 Engin. Fracture Mech. 53 169 [10] Lung C W and Wang L 1984 Philos. Mag. 50 L91 [11] Feng X Q, Mai Y W and Qin Q H 2003 Comput. Mater.Sci. 28 454 [12] Trinckauf K and Nembach E 1992 Philos. Mag. A 65 1383 [13] Stenkamp D and Jager W 1992 Philos. Mag. A 651369 [14] L in K M, Lin H C and Chen K C 1996 Engin. FractureMech. 54 395 [15] Hirth J P, Lothe J 1982 Theory of Dislocations (NewYork: John Wiley and Sons) [16] Read W T 1953 Dislocations in Crystals (New York:McGraw-Hill) 131
2009, Vol. 26 
