欢迎登录材料期刊网

材料期刊网

高级检索

  • 论文(20)
  • 图书()
  • 专利()
  • 新闻()

Orientation Dependence of Stress Rupture Properties of a Ni-based Single Crystal Superalloy at 760 oC

Shaohua Zhang

材料科学技术(英文)

The orientation dependence of creep rupture lives of a single crystal superalloy at 760 oC/760 MPa was investigated. The orientations of the specimens tested were about 30o away from [001]. The results showed that specimens with orientations on the [001]-[011] boundary had the longest rupture life. The deformation of these specimen were controlled by a/2<110> slip and a few stacking faults with two orientations were observed. On the other hand, specimens with orientations near the [001]-[011] boundary or on the [001]- [¹111] boundary showed short rupture lives, and stacking faults with single orientation were observed in these specimens. The rupture properties and the deformation mechanisms were discussed based on the dislocation
pattern and the calculated Schmid factors for different specimens..

关键词: Single crystal superalloy

Anisotropic Creep Rupture Properties of a Nickel-base Single Crystal Superalloy at High Temperature

Shaohua Zhang

材料科学技术(英文)

The stress rupture properties of a single crystal superalloy were tested at 975°C/255MPa as a function of the deviation degrees from [001]. The misorientation of the specimens away from [001] distributed approximately along a line between [001]-[011] and [001]-[-111] boundaries in the triangle of the stereographic projection. Creep rupture lifetimes of the specimens were not sensitive to the misorientation until the deviation degree exceeded ~30°. Two steps of lattice rotation were found in all specimens during creep, first towards the [001]-[-111] boundary, and then to [001] or [-111] along the boundary. Single slip and strong asymmetric deformation were observed during the first stage of lattice rotation in specimens with large misorientation. The rotation mechanism was associated with the activated slip systems according to the calculated Schmid factors. The impact of lattice rotation on the rupture properties was also discussed.

关键词: Dislocation

Ion sputter erosion in metallic glass-A response to "Comment on: Homogeneity of Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass" by L-Y. Chen, Y-W. Zeng, Q-P. Cao, B-J. Park, Y-M. Chen, K. Hono, U. Vainio, Z-L. Zhang, U. Kaiser, X-D. Wang, and J-Z Jiang J. Mater. Res. 24, 3116 (2009)

Journal of Materials Research

The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.

关键词: room-temperature

Broer-Kaup-Kupershmidt方程的新精确解

杨立娟 , 杨琼芬 , 杜先云

量子电子学报 doi:10.3969/j.issn.1007-5461.2012.02.003

CK方法是求解非线性发展方程的一种有效的直接方法.利用推广的CK方法,求得(2+1)维Broer-Kaup-Kupershmidt方程的Backlund公式,从而获得方程的大量新的精确解,推广了Xu和Zhang的结果.

关键词: 非线性发展方程 , Broer-Kaup-Kupershmidt方程 , 精确解 , CK方法 , Backlund变换

Three-dimensional (3D) Ising universality in magnets and critical indices at fluid-fluid phase transition

Phase Transitions

Experimental data for critical exponents in some magnetic materials are compared with recent theoretical results on the three-dimensional (3D) Ising model, as derived by one of us (ZDZ) based on two conjectures [Z.D. Zhang, Conjectures on the exact solution of three-dimensional (3D) simple orthorhombic Ising lattices, Phil. Mag. 87 (2007), pp. 5309-5419]. It is found that critical exponents in some bulk magnetic materials indeed form a 3D Ising universality. Our attention is then focused on the critical indices at fluid-fluid phase transition. We suggest to use Zhang's exponent = 3/8 to fit the experimental data over the wider asymptotic region near the critical point of a fluid-fluid phase transition. The 3D Ising universality should exist for critical indices in a certain class of magnets and at fluid-fluid phase transition.

关键词: magnetically ordered materials;fluid-fluid;phase transitions;order-disorder effects;ferromagnetic curie temperature;liquid critical phenomena;x-ray-scattering;critical exponents;critical-point;coexistence;curves;binary-solutions;ionic-solutions;behavior;equation

Response to the Comment on 'Conjectures on exact solution of three-dimensional (3D) simple orthorhombic Ising lattices'

Philosophical Magazine

The error of Equation (15b) in my article [Z.D. Zhang, Phil. Mag. 87 (2007) p.5309] in the application of the Jordan-Wigner transformation does not affect the validity of the putative exact solution, since the solution is not derived directly from that equation. Other objections of Perk's comment [J.H.H. Perk, Phil. Mag. 89 (2009) p.761] are the same as those in Wu et al.'s comments [F.Y. Wu et al., Phil. Mag. 88 (2008) p.3093; p.3103], which do not stand on solid ground and which I have sought to refute in my previous response [Z.D. Zhang, Phil. Mag. 88 (2008) p.3097]. The conjectured solution can be utilized to understand critical phenomena in various systems, whereas the conjectures are open to rigorous proof.

关键词: 3D Ising model;exact solution;conjecture;critical phenomena;ferromagnetism;magnetic phase transition;model;analyticity

  • 首页
  • 上一页
  • 1
  • 2
  • 下一页
  • 末页
  • 共2页
  • 跳转 Go

出版年份

刊物分类

相关作者

相关热词