FATIGUE CRACK INITIATION AND GROWTH-BEHAVIOR OF CU-16 AT-PERCENT AL SINGLE-CRYSTALS

被引：32

作者：

HONG, SI ^{[1
]}

LAIRD, C ^{[1
]}

机构：

[1] UNIV PENN,DEPT MAT SCI & ENGN,PHILADELPHIA,PA 19104

来源：

FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES | 1991年 / 14卷 / 2-3期

关键词：

D O I：

10.1111/j.1460-2695.1991.tb00650.x

中图分类号：

TH [机械、仪表工业];

学科分类号：

0802 ;

摘要：

In an attempt to understand the fatigue crack initiation and growth behavior of planar slip alloys, studies have been carried out in strain control on Cu‐16 at.% A1 single crystals oriented for easy glide. Alloy single crystals of Cu‐16 at.% A1 do not show saturation like copper crystals, but harden slowly and steadily throughout life, for the whole range of amplitudes applied. Cracks, the initiation and growth of which were studied by the sharp corner technique, were found to initiate when the peak stress reached 32 MPa irrespective of strain amplitude. The distribution of crack sizes in Cu‐16 at.% A1 single crystals was found to be more skewed to small cracks than that of copper. This behavior is attributed to the frequent migration of the bands of localized slip in this material. The fatigue lives of this alloy at low strain amplitudes (ypm < 6‐7 × 10−3) were found to be longer than those of copper single crystals because the strain is distributed more homogeneously than in copper. At high strain amplitudes, however, they become shorter because of the higher peak stress. The fatigue lives of Cu‐A1 crystals are predicted from those of copper on the basis of the different volume fractions of localized strain in the two materials; the prediction agrees well with the actual lives of Cu‐Al crystals. By geometrical consideration of secondary slip planes with respect to a primary crack, it was found that the critical system (A6) is most favored for secondary cracking adjacent to a primary crack. Copyright © 1991, Wiley Blackwell. All rights reserved

引用

页码：143 / 169

页数：27

共 57 条

[1]

Avery D.H., Backofen W.A., Nucleation and growth of fatigue cracks, Fracture of Solids, pp. 339-382, (1962)

[2]

Saxena A., Antolovich S.D., Low cycle fatigue, fatigue crack propagation and substructures in a series of polycrystalline Cu‐A1 alloys, Metall. Trans., 6 A, (1975)

[3]

Laird C., Feltner C.E., The Coffin‐Manson law in relation to slip character, Trans. Am. Inst. Min. Engrs, 239, pp. 1074-1083, (1967)

[4]

Lukas P., Klesnil M., Cyclic stress‐strain response and fatigue life of metals in low amplitude region, Materials Science and Engineering, 11, pp. 345-356, (1973)

[5]

Lukas P., Klesnil M., Polak J., High cycle fatigue life of metals, (1972)

[6]

Abel A., Wilhelm M., Gerold V., Low cycle fatigue of single crystals of α Cu‐A1 alloys, Mater. Sci. Engng, 37, pp. 187-200, (1979)

[7]

Yan B.D., Cheng A.S., Buchinger L., Stanzl S., Laird C., The cyclic stress‐strain response of Cu‐16 at.% A1 alloy, Part I, Mater. Sci. Engng, 80, pp. 129-142, (1986)

[8]

Buchinger L., Cheng A.S., Stanzl S., Laird C., The cyclic stress‐strain response of Cu‐16 at.% A1 alloy, Part II, Materials Science and Engineering, 80, pp. 155-167, (1986)

[9]

Hong S.I., Laird C., Cyclic deformation of Cu‐16 at.% A1 single crystals, Part I, strain burst behavior, Mater. Sci. Engng, 124 A, pp. 183-202, (1990)

[10]

Hong S.I., Laird C., Cyclic deformation of Cu‐16at.% A1 single crystals, Part II, cyclic hardening and slip band behavior, Mater. Sci. Engng., 128 A, pp. 55-75, (1990)

← 1 2 3 4 5 6 →