## O

Sketch of the surface-nanocrystallization principle for a coarse-grained metal undergoing the ultrasonic shot peening (USP) technique. Fig. 1. Sketch of the surface-nanocrystallization principle for a coarse-grained metal undergoing the ultrasonic shot peening (USP) technique. Fig. 2. Statistically averaging grain sizes changing with the distance away from the nanocrystal-line(NC) surface of Al-alloy material. Fig. 2. Statistically averaging grain sizes changing with the distance away...

## Cos1250 1245cosO750

The order of the mlcro-stress fleld ln Eqs. (8) ls stronger than that of the macro-stress fleld ln Eqs. (2). The angular dlstrlbutlon of the stresses are also dlfferent. If the applled unlform stress far away from the mlcro-crack ls also o , then the mlcro-stress lntenslty factor can be wrltten as Based on the physlcal models used ln Flgs. 1 to 3 and the dlfference of the stress fleld of Eqs. (2) and (8), the fracture behavlor of mlcro-cracks and macro-cracks ls dlfferent. One of the...

## Info

Crack length a+r versus the number of cycles for the lap joint tests in 0,0-0,0. References 1 Yamakov V, Phillips DR, Seather E, Glaessgen EH, Multiscale modelling of stress localization and fracture in nanocrystalline metallic materials. Nanoengineering of Structural, Functional and Smart Materials. Ed. M. J. Schlz, 2005. 2 McMillian JC, Pelloux RMN, Fatigue crack propagation, In Fatigue crack growth under spectrum loads, ASTM STP 415, page 505. American Society for Testing and...

## A multiscale field theory Nanomicro materials

Xiong Department of Mechanical and Aerospace Engineering The George Washington University, Washington, DC 20052, USA A multiscale field theory is proposed for the application of nano micro materials. Field representation of the conservation equations, stress, strains and stress-strain relation are formulated. Preliminary numerical examples from the new theory are presented. The atomic view of a crystal is considered as a periodic arrangement of local atomic...

## Azo

In equilibrium MD, it is assumed that this time-interval average reliably approxi- mates the time average (A), (a) T,im j A(r(x), p(x))dx, which would be obtained from a measurement performed over an essentially infinite duration, i.e., Am (A) (23) In statistical mechanics a macroscopic quantity is defined as the ensemble average of an instantaneous dynamical function (A) J A(r,p)f (r,p, t)drdp (24) where f is the normalized probability density function, i.e., jjf(r,p, t)drdp 1. Eq. (24)...

## Koj

The presence of the micro-stress intensity factor K cro in Eqs. (9) is reflected via where A2 is given by the second of Eqs. (5). Displayed in Figs. 9, 10 and 11 are the micro-stress intensity factor in Eq. (10) as a function of the ratio h g when the applied shear is fixed at 10MPa. With fixed t2 t1 5 and t1 tm 1, 2, 3 and 4, Fig. 9 shows that Km* stays nearly constant for each ratio Ti T with increasing amplitude of K cro as the shear stress ratio Ti T is increased. The same conclusion can be...

## By What Is Lattice Constant Denoted Audi

The obtained equilibrium configurations of dislocation lines when a strong misfit center exists (due the volumetric misfit) are presented in Figs. 8(a) and 8(b). These are obtained by varying the Peierls-Nabarro stress barrier when the applied stress is fixed. Similarly to Fig. 7, the dislocation lines are pinned by the misfit center but two equilibrium solutions can be found for each given materials misfit and applied stress. The first one shows the same trend as that in Fig. 7 but with...

## G2 J

The calculated additional GB resistance Ax at different strain amplitudes is listed in Table 3. It can be seen that Axas is also increased with increasing strain amplitude. From the analysis and calculations above, it seems that the existence of a GBAZ with a higher stress may be responsible for the increase in the cyclic saturation stress and the disappearance of the plateau region in the CSSC of the really grown bicrystal RB. 4. Effects of Crystallographic Orientations and Perpendicular GBs...

## Contributors

Aravas N Department of Mechanical and Industrial Engineering, University of Thessaly, Volos, Greece, Email Aravas mie.uth.gr Bai YL LNM, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, China, Email Baiyl lnm.imech.ac.cn Barter SA Defence Science and Technology Organisation Victoria 3207Australia, Email simon.barter dsto.defence.gov.au Chen FG Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100080, China, Email fgchen home.ipe.ac.cn Chen JS Civil amp...