Wenlin HE
,
Qishan ZANG+
,
Zhongguang WANG
,
State Key Laboratory for Fatigue and Fracture of Materials
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang
,
110015
,
China
材料科学技术（英文）
The distributions of plastic strain near grain boundaries induced by fatigue loading were investigated by the fiducial grid method in pure aluminum specimens, and the resulted grain boundary sliding (GBS) was systematically analysed. The results show that the strain field near a grain boundary is nonuniform. GBS is restricted by the junction of grain boundaries and causes discontinuities of both displacement and strain. A peak value of shear strain was created in short-range area across the grain boundary. GBS plays an important role in cyclic softening and secondary hardening. The control fac- tor of GBS is the relative orientation between two grains and the macro orientation of the grain boundary rather than the ∑ value of the boundary.
关键词:
grain boundary sliding
,
null
,
null
,
null
Zhongguang WANG
,
Xiaowu LI
,
Zhefeng ZHANG
,
Weiping JIA
,
Shouxin LI
材料科学技术（英文）
In the present work, the cyclic deformation behavior of Cu single crystals oriented for double- and multiple slip as well as Cu bicrystals and tricrystals was investigated under constant plastic strain control at room temperature in air. The main objectives of the study are: (1) to find out the effects of crystallographic orientation and grain boundary (GB) on the cyclic stress-strain (CSS) curves; (2) to compare the cyclic deformation behavior of the double-, multiple-slip crystals, bicrystals and tricrystals with that of single-slip oriented crystals and to correlate the results with those of polycrystals; (3) to examine the corresponding dislocation structures; (4) to investigate the interactions of persistent slip bands (PSBs) with GBs and triple joint (TJ) as well as intergranular fatigue cracking in Cu bicrystals and tricrystals.
关键词:
