The Experts below are selected from a list of 43452 Experts worldwide ranked by ideXlab platform
Li Longbiao - One of the best experts on this subject based on the ideXlab platform.
-
Damage Monitoring of Unidirectional C/SiC Ceramic-Matrix Composite under Cyclic Fatigue Loading using A Hysteresis Loss Energy-Based Damage Parameter at Room and Elevated Temperatures
Applied Composite Materials, 2015Co-Authors: Li LongbiaoAbstract:The Damage evolution of unidirectional C/SiC ceramic-matrix composite (CMC) under cyclic fatigue loading has been investigated using a hysteresis loss energy-based Damage Parameter at room and elevated temperatures. The experimental fatigue hysteresis modulus and fatigue hysteresis loss energy versus cycle number have been analyzed. By comparing the experimental fatigue hysteresis loss energy with theoretical computational values, the interface shear stress corresponding to different cycle number and peak stress has been estimated. The experimental evolution of fatigue hysteresis loss energy and fatigue hysteresis loss energy-based Damage Parameter versus cycle number has been predicted for unidirectional C/SiC composite at room and elevated temperatures. The predicted results of interface shear stress degradation, stress–strain hysteresis loops corresponding to different number of applied cycles, fatigue hysteresis loss energy and fatigue hysteresis loss energy-based Damage Parameter as a functions of cycle number agreed with experimental data. It was found that the fatigue hysteresis energy-based Parameter can be used to monitor the fatigue Damage evolution and predict the fatigue life of fiber-reinforced CMCs.
-
a hysteresis dissipated energy based Damage Parameter for life prediction of carbon fiber reinforced ceramic matrix composites under fatigue loading
Composites Part B-engineering, 2015Co-Authors: Li LongbiaoAbstract:Abstract Under fatigue loading, the stress–strain hysteresis loops appear as fiber slipping relative to matrix in the interface debonded region. The area of hysteresis loops, i.e., the hysteresis dissipated energy, changes with the increase of cycle number, and can reveal fatigue Damage mechanisms, i.e., matrix multicracking, fiber/matrix interface debonding, interface slipping, interface wear, and fibers fracture. Based on the fatigue hysteresis theories considering fibers failure, the hysteresis dissipated energy and a hysteresis dissipated energy-based Damage Parameter changing with the increase of cycle number have been investigated. The relationships between the hysteresis dissipated energy, hysteresis dissipated energy-based Damage Parameter, stress–strain hysteresis loops, and fatigue Damage mechanisms have been established. The effects of fatigue peak stress, stress ratio, matrix crack spacing and fiber volume content on the evolution of hysteresis dissipated energy and hysteresis dissipated energy-based Damage Parameter as a function of cycle number have been analyzed. It was found that the hysteresis dissipated energy-based Damage Parameter is much more sensitive to interface debonding and interface frictional slipping compared with the hysteresis dissipated energy under fatigue loading, and can be used to reveal the fatigue Damage evolution and predict the fatigue life of fiber-reinforced CMCs. The experimental fatigue life S–N curves of unidirectional CMCs have been predicted using the present analysis.
-
a hysteresis dissipated energy based Parameter for Damage monitoring of carbon fiber reinforced ceramic matrix composites under fatigue loading
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2015Co-Authors: Li LongbiaoAbstract:Abstract Under fatigue loading of fiber-reinforced ceramic–matrix composites (CMCs), the stress−strain hysteresis loops appear as fiber slipping relative to matrix in the interface debonded region. The area of hysteresis loops, i.e., the hysteresis dissipated energy, changes with the increase of cycle number, which can reveal the fatigue Damage mechanisms, i.e., matrix multicracking, fiber/matrix interface debonding, interface slipping and interface wear. Based on the fatigue hysteresis theories, the relationships between hysteresis dissipated energy, hysteresis dissipated energy-based Damage Parameter, stress−strain hysteresis loops, and fatigue Damage mechanisms have been established. The effects of fiber volume content, fatigue peak stress, fatigue stress ratio and matrix crack spacing on the evolution of the hysteresis dissipated energy and hysteresis dissipated energy-based Damage Parameter as a function of cycle number have been analyzed. The experimental hysteresis dissipated energy and hysteresis dissipated energy-based Damage Parameter of unidirectional CMCs corresponding to different fatigue peak stresses and cycle numbers have been predicted using the present analysis. It was found that the hysteresis energy-based Parameter can be used to monitor the fatigue Damage evolution and predict the fatigue life of fiber-reinforced CMCs.
Zhengyong Yu - One of the best experts on this subject based on the ideXlab platform.
-
a new energy critical plane Damage Parameter for multiaxial fatigue life prediction of turbine blades
Materials, 2017Co-Authors: Zhengyong YuAbstract:As one of fracture critical components of an aircraft engine, accurate life prediction of a turbine blade to disk attachment is significant for ensuring the engine structural integrity and reliability. Fatigue failure of a turbine blade is often caused under multiaxial cyclic loadings at high temperatures. In this paper, considering different failure types, a new energy-critical plane Damage Parameter is proposed for multiaxial fatigue life prediction, and no extra fitted material constants will be needed for practical applications. Moreover, three multiaxial models with maximum Damage Parameters on the critical plane are evaluated under tension-compression and tension-torsion loadings. Experimental data of GH4169 under proportional and non-proportional fatigue loadings and a case study of a turbine disk-blade contact system are introduced for model validation. Results show that model predictions by Wang-Brown (WB) and Fatemi-Socie (FS) models with maximum Damage Parameters are conservative and acceptable. For the turbine disk-blade contact system, both of the proposed Damage Parameters and Smith-Watson-Topper (SWT) model show reasonably acceptable correlations with its field number of flight cycles. However, life estimations of the turbine blade reveal that the definition of the maximum Damage Parameter is not reasonable for the WB model but effective for both the FS and SWT models.
-
a new energy critical plane Damage Parameter for multiaxial fatigue life prediction of turbine blades
Materials, 2017Co-Authors: Zhengyong YuAbstract:As one of fracture critical components of an aircraft engine, accurate life prediction of a turbine blade to disk attachment is significant for ensuring the engine structural integrity and reliability. Fatigue failure of a turbine blade is often caused under multiaxial cyclic loadings at high temperatures. In this paper, considering different failure types, a new energy-critical plane Damage Parameter is proposed for multiaxial fatigue life prediction, and no extra fitted material constants will be needed for practical applications. Moreover, three multiaxial models with maximum Damage Parameters on the critical plane are evaluated under tension-compression and tension-torsion loadings. Experimental data of GH4169 under proportional and non-proportional fatigue loadings and a case study of a turbine disk-blade contact system are introduced for model validation. Results show that model predictions by Wang-Brown (WB) and Fatemi-Socie (FS) models with maximum Damage Parameters are conservative and acceptable. For the turbine disk-blade contact system, both of the proposed Damage Parameters and Smith-Watson-Topper (SWT) model show reasonably acceptable correlations with its field number of flight cycles. However, life estimations of the turbine blade reveal that the definition of the maximum Damage Parameter is not reasonable for the WB model but effective for both the FS and SWT models.
M. Panbechi - One of the best experts on this subject based on the ideXlab platform.
-
An energy-based fatigue Damage Parameter for off-axis unidirectional FRP composites
Composite Structures, 2007Co-Authors: A. Varvani-farahani, H. Haftchenari, M. PanbechiAbstract:Abstract An energy-based fatigue Damage Parameter has been developed to assess the fatigue Damage of unidirectional glass-reinforced plastic (GRP) and carbon-fiber reinforced plastic (CFRP) composites. The proposed Parameter is based on the physics and the mechanism of fatigue cracking within three Damage regions of matrix (I), fiber–matrix interface (II), and fiber (III) in these materials as the number of cycles progresses. The Parameter involves the shear and normal energies calculated from stress and strain components acting on these region. In region I the Damage was initiated in the form of microcracks within the matrix. For region II, the Damage progress took place along the matrix–fiber interface leading to fiber fracture in region III. The proposed fatigue Damage model successfully correlated fatigue lives of unidirectional GRP and CFRP composites at various off-axis angles θ and stress ratios R. The results of fatigue Damage assessment revealed that the proposed Damage Parameter correlated fatigue data with a higher degree of success as compared with fatigue Damage Parameters developed earlier.
-
a fatigue Damage Parameter for life assessment of off axis unidirectional grp composites
Journal of Composite Materials, 2006Co-Authors: A Varvanifarahani, H. Haftchenari, M. PanbechiAbstract:The present study develops a fatigue Damage Parameter to assess the fatigue Damage of unidirectional glass fiber reinforced plastic (GRP) composites. The proposed Parameter is based on the physics and the mechanism of fatigue cracking within three Damage regions of matrix (I), fiber-matrix interface (II), and fiber (III) in these materials as the number of cycles progresses. In region I, Damage was initiated in the form of microcracks within the matrix. For region II, Damage progress took place along the matrix-fiber interface leading to fiber fracture in region III. The proposed fatigue Damage model successfully correlated fatigue lives of unidirectional GRP composites at various off-axis angles and stress ratios R as compared with other earlier developed fatigue Parameters.
-
a fatigue Damage Parameter for life assessment of off axis unidirectional grp composites
Journal of Composite Materials, 2006Co-Authors: A Varvanifarahani, H. Haftchenari, M. PanbechiAbstract:The present study develops a fatigue Damage Parameter to assess the fatigue Damage of unidirectional glass fiber reinforced plastic (GRP) composites. The proposed Parameter is based on the physics ...
Deguang Shang - One of the best experts on this subject based on the ideXlab platform.
-
equivalent energy based critical plane fatigue Damage Parameter for multiaxial lcf under variable amplitude loading
International Journal of Fatigue, 2020Co-Authors: Long Xue, Deguang Shang, Xiaodong Liu, Hong ChenAbstract:Abstract Combining the concept of energy on the critical plane, a multiaxial fatigue Damage Parameter without any weight coefficient was proposed and the effects of non-proportional additional hardening and mean stress on fatigue Damage can be reflected more perfectly using an equivalent form of shear strain energy. Furthermore, two sets of experimental data are employed to verify the proposed method, and the sensitiveness to fatigue life of the proposed equivalent stress correction factor is discussed as well. The results show that satisfactory and conservative assessments can be obtained by the proposed method, especially under multiaxial irregular loading with great randomness.
-
fatigue life prediction under variable amplitude axial torsion loading using maximum Damage Parameter range method
International Journal of Pressure Vessels and Piping, 2013Co-Authors: Hong Chen, Deguang Shang, Yujie Tian, Jianzhong LiuAbstract:Abstract This article deals with the problem of multiaxial fatigue life assessment under variable amplitude axial–torsion loading. A maximum Damage Parameter range (MDPR) reversal counting method is proposed to predict fatigue life under variable amplitude multiaxial loading. First, a multiaxial fatigue Damage Parameter is selected for a given multiaxial loading time history. Then, a Damage Parameter range time history can be calculated. Finally, based on the MDPR method, fatigue life can be predicted by correlating with multiaxial fatigue Damage model and the Miner–Palmgren Damage rule. The proposed method is evaluated with experimental data of the 7050-T7451 aluminum alloy and En15R steel under variable amplitude multiaxial loading. The results demonstrated that the proposed method can provide satisfactory prediction.
-
multiaxial fatigue Damage Parameter and life prediction for medium carbon steel based on the critical plane approach
International Journal of Fatigue, 2007Co-Authors: Deguang Shang, Jing DengAbstract:Abstract The tension–torsion fatigue characteristics were investigated under proportional and non-proportional loading in this paper. The fatigue cracks on the surface of multiaxial fatigue specimens were observed and analyzed by a scan electron microscope. On the basis of the investigation on the Kindil–Brown–Miller and Fatemi–Socie’s critical plane approaches, a shear strain based multiaxial fatigue Damage Parameter was proposed by von Mises criterion based on combining the maximum shear strain and the normal strain excursion between adjacent turning points of the maximum shear strain on the critical plane. The proposed multiaxial fatigue Damage Parameter does not include the weight constants. According to the proposed multiaxial fatigue Damage Parameter, the multiaxial fatigue life prediction model was established with the Coffin–Manson equation, which is used to predict the multiaxial fatigue life of medium-carbon steel. The results showed that the proposed multiaxial fatigue Damage Parameter could be used under either multiaxial proportional or non-proportional loading.
-
a unified multiaxial fatigue Damage Parameter
Acta Mechanica Solida Sinica, 1998Co-Authors: Deguang Shang, D Wang, A PingAbstract:According to the critical plane principle, a unified multiaxial fatigue Damage Parameter is presented based on the varying behaviour of the strains on the critical plane. Both the Parameters of the maximum shear strain amplitude and normal strain excursion between adjacent turning points of the maximum shear strain on the critical plane are considered in the multiaxial fatigue Damage Parameter presented. An equivalent strain amplitude is made with both Parameters of the maximun shear strain amplitude and normal strain excursion by means of von Mises criterion. Thus a new multiaxial fatigue Damage model is given based on the critical plane approach. The results show that the multiaxial fatigue Damage Parameter proposed in this paper may be used under either proportional or nonproportional loading, and may also be reduced to a uniaxial form. It is used to predict multiaxial fatigue life and good agreement is demonstrated by experimental data.
A. Varvani-farahani - One of the best experts on this subject based on the ideXlab platform.
-
An energy-based fatigue Damage Parameter for off-axis unidirectional FRP composites
Composite Structures, 2007Co-Authors: A. Varvani-farahani, H. Haftchenari, M. PanbechiAbstract:Abstract An energy-based fatigue Damage Parameter has been developed to assess the fatigue Damage of unidirectional glass-reinforced plastic (GRP) and carbon-fiber reinforced plastic (CFRP) composites. The proposed Parameter is based on the physics and the mechanism of fatigue cracking within three Damage regions of matrix (I), fiber–matrix interface (II), and fiber (III) in these materials as the number of cycles progresses. The Parameter involves the shear and normal energies calculated from stress and strain components acting on these region. In region I the Damage was initiated in the form of microcracks within the matrix. For region II, the Damage progress took place along the matrix–fiber interface leading to fiber fracture in region III. The proposed fatigue Damage model successfully correlated fatigue lives of unidirectional GRP and CFRP composites at various off-axis angles θ and stress ratios R. The results of fatigue Damage assessment revealed that the proposed Damage Parameter correlated fatigue data with a higher degree of success as compared with fatigue Damage Parameters developed earlier.
