全文获取类型
收费全文 | 498篇 |
免费 | 7篇 |
国内免费 | 7篇 |
专业分类
化学 | 37篇 |
晶体学 | 2篇 |
力学 | 374篇 |
综合类 | 2篇 |
数学 | 39篇 |
物理学 | 58篇 |
出版年
2022年 | 3篇 |
2021年 | 1篇 |
2020年 | 7篇 |
2019年 | 2篇 |
2018年 | 8篇 |
2017年 | 13篇 |
2016年 | 18篇 |
2015年 | 12篇 |
2014年 | 37篇 |
2013年 | 17篇 |
2012年 | 10篇 |
2011年 | 29篇 |
2010年 | 33篇 |
2009年 | 41篇 |
2008年 | 48篇 |
2007年 | 32篇 |
2006年 | 31篇 |
2005年 | 31篇 |
2004年 | 38篇 |
2003年 | 32篇 |
2002年 | 25篇 |
2001年 | 5篇 |
2000年 | 6篇 |
1999年 | 4篇 |
1998年 | 9篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1990年 | 3篇 |
1989年 | 8篇 |
排序方式: 共有512条查询结果,搜索用时 15 毫秒
81.
Understanding crack growth in fuselage lap joints 总被引:1,自引:1,他引:0
The problem of multi-site damage and multiple interacting cracks is one experienced by many aircraft manufacturers and operators. This paper focuses on understanding the phenomena, and on developing a predictive capability that can form the engineering framework for maintaining continued airworthiness. To this end the present paper uses a simple formulation based on the Frost–Dugdale crack growth law to study the problem of cracking at fastener holes in fuselage lap joints and shows that the predicted crack growth history is in good agreement with both experimental results and with fleet data. 相似文献
82.
H. G. Beom Y. H. Kim C. B. Kim C. Cho 《Archive of Applied Mechanics (Ingenieur Archiv)》2008,78(3):191-209
A thin electrode embedded in an electrostrictive material under electric loading is investigated. In order to obtain an asymptotic
form of electric fields and elastic fields near the electrode edge, we consider a modified boundary layer problem of an electrode
in an electrostrictive material under the small scale saturation condition. The exact electric solution for the electrode
is obtained by using the complex function theory. It is found that the shape of the electric displacement saturation zone
is sensitive to the transverse electric displacement. A perturbation solution of stress fields induced by incompatible electrostrictive
strains for the small value of the transverse electric displacement is obtained. The influence of transverse electric displacement
on a microcrack initiation from the electrode edge is also discussed. 相似文献
83.
Jong-Bong Kim Hyunho Shin Woong Lee Kyong Yop Rhee 《Archive of Applied Mechanics (Ingenieur Archiv)》2008,78(10):811-819
Deflection criterion for oblique cracks terminating at a bi-material interface was established numerically based on a remote
loading condition where the crack deflection event took place well within the K-dominant stress field. The criterion was described in terms of the ratio of the energy release rate of a deflected crack
(G
d) to the maximum energy release rate of a penetrated crack (). The criterion was markedly more conservative than the existing solution based on wedge loading which did not converge with
respect to limited number of a/L ratios in the literature (a is the size of the putative crack; L is the loading distance). Further, the criterion established herein for the cracks slightly oblique from the normal direction
to the interface was more conservative than the crack normal to the interface. 相似文献
84.
Bertrand François Cristian Dascalu 《Journal of the mechanics and physics of solids》2010,58(11):1928-1946
This paper presents the theoretical developments and the numerical applications of a time-dependent damage law. This law is deduced from considerations at the micro-scale where non-planar growth of micro-cracks, following a subcritical propagation criterion, is assumed. The orientation of the crack growth is governed by the maximum energy release rate at the crack tips and the introduction of an equivalent straight crack. The passage from micro-scale to macro-scale is done through an asymptotic homogenization approach. The model is built in two steps. First, the effective coefficients are calculated at the micro-scale in finite periodical cells, with respect to the micro-cracks length and their orientation. Then, a subcritical damage law is developed in order to establish the evolution of damage. This damage law is obtained as a differential equation depending on the microscopic stress intensity factors, which are a priori calculated for different crack lengths and orientations. The developed model enables to reproduce not only the classical short-term stress-strain response of materials (in tension and compression) but also the long-term behavior encountering relaxation and creep effects. Numerical simulations show the ability of the developed model to reproduce this time-dependent damage response of materials. 相似文献
85.
J. Chen 《Theoretical and Applied Fracture Mechanics》2010,53(1):74-79
Three different interatomic potentials, namely, B-G I Model, B-G II Model and L-C Model, are used in multiscale modeling and simulation of a center-cracked specimen made of magnesia subjected to monotonically increasing loading. The specimen is decomposed into a far field, a near field and a crack-tip region. The analytical solution in the far field from linear elastic fracture mechanics (LEFM) is utilized. The solution of the near field is based on a multiscale field theory. In the crack-tip region, molecular dynamics (MD) simulation is employed. These methodologies are integrated to simulate mixed mode fracture of magnesia (MgO). Three different interatomic potentials are examined and the interatomic potential and interatomic force between Mg-Mg, Mg-O and O-O are shown. The numerical results of crack propagation demonstrate that (1) crack closure is witnessed in B-G I Model but not in B-G II Model and L-C Model, (2) B-G II Model and L-C Model diverge in the early stage. The cause of instability and the remedy are also discussed. 相似文献
86.
G.A. Harmain 《Theoretical and Applied Fracture Mechanics》2010,53(1):80-37
Many engineering components are subjected to variable amplitude loading history. It is well known that retardation in fatigue crack growth occurs due to application of single overloads in a constant amplitude loading block. Many models have been proposed to capture this counter intuitive phenomenon which has resulted in improved understanding of retardation effect following tensile overloads and consequently resulting in better life prediction models. The proposed study is focused on to evaluation of retardation in fatigue life due to application of a single overload. A model for prediction of crack growth and crack growth rate following single overloads is presented. Several modifications to Wheeler’s growth idea are proposed, which incorporate a consideration for effective stress intensity factor, based on Elber’s concept of crack closure, relationship between overload ratio and the Wheeler’s exponent, and fatigue growth rate calculations. The results presented here show that plastic zone interaction following overload and the consideration of crack closure explain retardation effect following a single overload. Correlation between analysis and experimental data obtained from several sources in literature show that the scheme, is robust and provides an insight into the nonlinear aspect of crack growth results. The model has been tested for 2024-T3 aluminum alloy and 6061-T6 aluminum alloy and thorough calibrations performed, established the fidelity of the program. 相似文献
87.
L. Marsavina R. Susan-Resiga N. Faur R. Negru 《Theoretical and Applied Fracture Mechanics》2010,53(2):136-144
The performance of engineering components and structures is strongly influenced by the interaction between design, manufacture and materials. A methodology to assess the integrity of a circular collector is presented by investigating the failure of copper lamellas. The investigated circular collector, having 315 copper lamellas, is one of the main parts of an electric motor. The fracture of the copper lamellas was observed in normal operation. This unexpected fracture required an investigation of the fracture origin, in order to improve the initial design. The numerical results of the finite element analysis on the stress field in the copper lamellas for the operating regimes, and the stress concentration effects are shown. Failure assessment diagram, based on notch stress intensity factor, was considered in order to estimate if crack initiation can occur. Finally a study of crack propagation will present comparatively the numerical obtained crack path against the one observed in-service. 相似文献
88.
89.
Pei-Wei Zhang Zhen-Gong Zhou Lin-Zhi Wu 《Archive of Applied Mechanics (Ingenieur Archiv)》2009,79(10):965-979
In this paper, the behavior of three parallel non-symmetric permeable cracks in a piezoelectric/piezomagnetic material plane
subjected to anti-plane shear stress loading was studied by the Schmidt method. The problem was formulated through Fourier
transform into three pairs of dual integral equations, in which unknown variables are jumps of displacements across the crack
surfaces. To solve the dual integral equations, the jumps of displacements across the crack surfaces were directly expanded
as a series of Jacobi polynomials. Finally, the relations among the electric displacement, the magnetic flux and the stress
fields near the crack tips can be obtained. The results show that the stress, the electric displacement and the magnetic flux
intensity factors at the crack tips depend on the lengths and spacing of cracks. It was also revealed that the crack shielding
effect is present in piezoelectric/piezomagnetic materials. 相似文献
90.
The influence of two transverse open cracks on the antiresonances of a double cracked cantilever beam is investigated both analytically and experimentally. It is shown that there is a shift in the antiresonances of the cracked beam depending on the location and size of the cracks. These antiresonance changes, complementary with natural frequency changes, can be used as additional information carrier for crack identification in double cracked beams. Experimental results from tests on plexiglas beams damaged at different locations and different magnitudes are found to be in good agreement with theoretical predictions. Based on the results of the present work, an efficient prediction scheme for crack localization and characterization in double cracked beams is proposed. 相似文献