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[资源] 有关纳米孪晶强化的最新综述- viewpoint set

scripta material上发表的有关纳米尺度孪晶的文章共有9篇，对过去的重要进展以及未来面临的重大问题进行了展望！
共分为四个方面：
1、变形机制及加工硬化篇
  金属所卢磊老师：有关加工硬化
  zhu T ,gao hj 计算模拟（1Woodruff School of Mechanical Engineering, Georgia Institute and Technology,Atlanta, GA 30332, USA）
2、疲劳行为
MIT Suresh S组有关repeated frictional sliding
金属所张哲峰  退火孪晶界萌生裂纹的判据
3、孪晶稳定性
zhang x ,misra  有关纳米孪晶退火稳定性（1Department of Mechanical Engineering, Materials Science and Engineering Program, Texas
A&M University, College Station, Texas）

Idrissil's groop Pd膜中孪晶形成机制（Department of Physics, University of Antwerp, Groenenborgerlaan 171, B-2020Antwerp, Belgium）

Hodge 不同载荷方式下的变形行为（aDepartment of Aerospace and Mechanical Engineering, University of Southern California, Los Angeles, CA 90089, USA）
4、应用篇
  金属所 LU K 在316L中引入纳米孪晶
  Harada'group 在高温合金中引入纳米孪晶（National Institute for Materials Science, Sengen 1-2-1, Tsukuba 305-0047, Japan）
详细的介绍看下面的英文介绍
TBs possess low excess energy, resulting in a number of superior properties relative toconventional GBs, such as higher thermal and mechanical stabilities, lower electricalresistivity and better corrosion resistance. TBs can be generated via crystal growth, phasetransformation, plastic deformation or recrystallization of deformed structure in metals andlloys. Hence, nanotwin strengthening is becoming a practical methodology for optimizingthe global properties and performance of engineering materials
The objective of this latest viewpoint set to be published in Scripta Materialia is to elucidatethe state of the art in this rapidly growing research field. Several key issues on the strengthening effect of nanotwins will be addressed, including strength–ductility synergy,strain hardening, fatigue and fracture behaviors, plastic deformation mechanism and stability of nanotwinned materials, including pure metals (model materials) and engineeringalloys such as austenitic steels and superalloys. Experimental studies combined withsimulation and modeling focus on revealing the underlying mechanism of nanotwintrengthening.
  This viewpoint set consists of nine invited articles, dealing with four important aspects of nanotwin strengthening, including deformation mechanism and work hardening of nanotwinned structures, fatigue and fracture in nanotwinned materials, thermal and mechanical stability of nanotwins, and the application of nanotwin strengthening. In the first two articles, Lu et al. analyze the principles and mechanisms governing the work hardening behavior of polycrystalline pure Cu with nanoscale twins. The contributions of several hardening and softening components in the nanotwinned structure in Cu are qualitatively
discussed. Zhu and Gao address the TB-mediated deformation mechanisms systematically by using molecular dynamics simulations, dislocation mechanics and crystal plasticity modeling in nanotwinned Cu。
The next two articles focus on the fatigue and fracture behaviors of nanotwinned structures in metals. Suresh’s group investigate the tribological properties of Cu specimens consisting ofnanotwinned and nanograined structures；Zhang et al. explore the fatigue cracking mechanisms at TBs and find that TB cracking is intrinsically determined bythe interactions between the TBs and dislocations (both piled-up and penetrated dislocations),which is controlled by the cooperative effects of the stacking fault energy, the slip mode and the crystallographic orientations in the matrix and the twins。
The thermal and mechanical stabilities of TBs are vital for the practical application of nanotwinned materials, and these are addressed in three articles. Zhang and Misra compare the thermal stability of a nanotwinned 330 stainless steel to their nanograined counterparts and find that coherent TBs have a superior thermal stability than high-angle GBs, owing to the energy stored at TBs being an order of magnitude lower than that at high-angle GBs. Idrissil’s group analyze the formation mechanism of nanotwin structures in Pd films and observe a high thermal stability of nanoscale growth twins. The stability of a nanotwin structure in Cu under different mechanical loading tests is explored by Hodge et al. They observe that the nanotwins are very stable against straining, although small microstructural
changes occur with different deformation modes. Various forms of destabilization of the nanotwinned structure under mechanical loadings are discussed, including shear bands, deformation-induced grain growth and detwinning.
  The set ends with two articles presenting applications of the nanotwin strengthening strategy in engineering materials. Lu’s group have succeeded in generating austenitic grains containing multiple nanotwins for strengthening conventional austenitic steels. Their measurement results reveal that the austenite nanotwinned grains are effective in elevating strength as well as work-hardening rates. The austenitic steels strengthened by nanotwinned austenitic grains
are found to exhibit superior strength–ductility synergies. Harada’s group demonstrate that disks of coarse-grained superalloys can be effectively strengthened by nanoscale twins at high service temperatures。[ Last edited by zhyq8767 on 2012-3-2 at 12:45 ]

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