Chiwei LUNG
,
Kang LONG
,
Enke TIAN
,
Zongjun LIANG
材料科学技术(英文)
The distortion regions near grain boundaries in cr-Fe-C solid solution were studied by use of internal friction method. It was found that the total thickness of these regions is quite large though the thickness of real grain boundaries is usually very thin. It was also found that the smaller the grain size, the thicker the total distortion region. A model for the structure of distortion regions near grain boundaries is proposed. Their effects on nanocrystalline materials are discussed.
关键词:
Jingyang WANG
,
Enke TIAN
,
Chiwei LUNG
材料科学技术(英文)
By using Morse potential model, we calculate the temperature dependence of critical resolved shear stress (CRSS) of some single crystals. Dislocation-phonon interaction is considered in this paper. Theoretical calculations fit experimental law well. Investigations show: interatomic force is the physical intrinsic that controls the plastic deformation processing of materials, and the temperature dependence of CRSS mainly comes from the temperature dependence of dislocation vibration.
关键词:
Chiwei LUNG
,
Enke TIAN
,
Hengqiang YE
材料科学技术(英文)
Introducing the stress distribution near grain boundaries to improve the dislocation pileup model for the Halt-Petch (H-P) relation, the continuous distribution of dislocations in the pileup could be solved by means of Tschebysheff polynomials for the Hilbert transformation. An analytical formula of the stress intensity factor for the dislocation pileup is obtained. The reverse H-P relation may be explained by the modified dislocation-pileup-model.
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