The Experts below are selected from a list of 471 Experts worldwide ranked by ideXlab platform
Xu Chen - One of the best experts on this subject based on the ideXlab platform.
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RATCHETING OF STAINLESS STEEL 304 UNDER MULTIAXIAL Nonproportional Loading
2020Co-Authors: Kwang S Kim, Rong Jiao, Xu Chen, Masao SakaneAbstract:ABSTRACT Ratcheting tests are conducted on stainless steel 304 under uniaxial, torsional, and combined axial-torsional Loading. The ratcheting strain is predicted based on the constitutive theory that incorporates a modified Ohno-Wang kinematic hardening rule and Tanaka's isotropic hardening model. The results show that the main features of the stress-strain response can be simulated with the constitutive model. The experimental and predicted ratcheting strains for Nonproportional paths are found in decent correlation. Ratcheting strain depends highly on the Loading path and load level, and less on cyclic hardening or softening of the material. The torsional ratcheting strain under mean shear stress with (or without) fully reversed axial strain cycling is found close to the axial ratcheting strain under equivalent mean stress with (or without) torsional strain cycling
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the effects of Nonproportional Loading on the elastic plastic crack tip fields
Engineering Fracture Mechanics, 2017Co-Authors: Zhaoyu Jin, Xin Wang, Xu ChenAbstract:Abstract In this paper, the biaxial Loading path effects on the mode I plane strain elastic-plastic crack-tip stress fields are investigated computationally. First, three different Loading sequences including one proportional Loading and two non-proportional Loading paths are applied to the modified boundary layer (MBL) model under small-scale yielding conditions. For the same external displacement field applied at the outer boundary of the MBL model, the mode I K field and T-stress field combined as the different Loading paths are applied to investigate the influence of the Nonproportional Loading. The results show that for either the compressive or tensile T -stress, the Loading path which applied K field first followed by T-stress field generates the lower crack-tip constraint comparing to proportional Loading. There is only minor difference between the results from proportional Loading path and that with the T-stress field applied first following by K field. Next, two finite width specimens under non-proportional biaxial Loading conditions that generate the same three Loading paths are analyzed. Similar crack tip characteristics are observed in these specimens as these obtained from the MBL model, and it is demonstrated that the near-tip behavior in specimens can be predicted accurately using the results from MBL models. The present results show that it is very important to include the load sequence effects in elastic-plastic fracture analysis when dealing with Nonproportional Loading conditions.
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the effects of Nonproportional Loading on the elastic plastic crack tip fields
Applied Mechanics and Materials, 2016Co-Authors: Zhaoyu Jin, Xin Wang, Xu ChenAbstract:In this paper, the Loading path effects on the plane strain elastic-plastic crack-tip stress field are investigated computationally. Three different Loading sequences include one proportional Loading and two non-proportional Loading paths are applied to the modified boundary layer (MBL) model under small-scale yielding conditions. For the same external displacement field applied at the outer boundary of the MBL model, the mode I K field and T-stress field combined as the different Loading paths are applied to investigate the influence of the Nonproportional Loading. The results show that for either the compressive or tensional T-stress, the Loading path which applied K field followed by T field generates the lower crack-tip constraint. There is only slightly difference between the proportional Loading path and that with the T-stress field following by K field. The results show that it is very important to include the load sequence effects in fracture analysis when dealing with Nonproportional Loading conditions.
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Ratcheting of Stainless Steel 304 Under Multiaxial Nonproportional Loading
Volume 1: Codes and Standards, 2007Co-Authors: Rong Jiao, Xu Chen, Masao SakaneAbstract:Ratcheting tests are conducted on stainless steel 304 under uniaxial, torsional, and combined axial-torsional Loading. The ratcheting strain is predicted based on the constitutive theory that incorporates a modified Ohno-Wang kinematic hardening rule and Tanaka’s isotropic hardening model. The results show that the main features of the stress-strain response can be simulated with the constitutive model. The experimental and predicted ratcheting strains for Nonproportional paths are found in decent correlation. Ratcheting strain depends highly on the Loading path and load level, and less on cyclic hardening or softening of the material. The torsional ratcheting strain under mean shear stress with (or without) fully reversed axial strain cycling is found close to the axial ratcheting strain under equivalent mean stress with (or without) torsional strain cycling.Copyright © 2007 by ASME
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A Simple Inelastic Constitutive Model for Evaluation of Stable Cyclic Stress Response under Nonproportional Straining
2002Co-Authors: Ito Takamoto, Sakane Masao, Xu ChenAbstract:This paper proposes a simple two-surfacce model for cyclic incremental plasticity based on combined Mroz and Ziegler kinematic hardering hardening rules under Nonproportional Loading. The model has only seven material constants and a Nonproportional factor which describes the degree of additional hardening. Cyclic Loading experiments with fourteen strain paths were conducted using Type 304 stainless steel. The simulation has showen that the model was precise enought to calculate the stable cyclic stress-strain relationship under Nonproportional Loadings
Masao Sakane - One of the best experts on this subject based on the ideXlab platform.
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RATCHETING OF STAINLESS STEEL 304 UNDER MULTIAXIAL Nonproportional Loading
2020Co-Authors: Kwang S Kim, Rong Jiao, Xu Chen, Masao SakaneAbstract:ABSTRACT Ratcheting tests are conducted on stainless steel 304 under uniaxial, torsional, and combined axial-torsional Loading. The ratcheting strain is predicted based on the constitutive theory that incorporates a modified Ohno-Wang kinematic hardening rule and Tanaka's isotropic hardening model. The results show that the main features of the stress-strain response can be simulated with the constitutive model. The experimental and predicted ratcheting strains for Nonproportional paths are found in decent correlation. Ratcheting strain depends highly on the Loading path and load level, and less on cyclic hardening or softening of the material. The torsional ratcheting strain under mean shear stress with (or without) fully reversed axial strain cycling is found close to the axial ratcheting strain under equivalent mean stress with (or without) torsional strain cycling
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n a l Low Cycle Fatigue -Experiment and FEM Analysis - Tomoshige SUSAKI
2020Co-Authors: Masao Sakane, Graduate Student, Tsuneo Itoh, Yoshiyasu KawazoeAbstract:ABSTRACT This paper studies the low cycle fatigue of circumferential notched specimens of type 304 stainless steel in Nonproportional Loading. Strain controlled tension-torsion low cycle fatigue tests were carried out using the notched specimens under 15 strain paths. Crack initiation lives detected by a d.c. potential method were discussed in relation to the strain concentration factors and strain histories. Finite element analyses were carried out for evaluating the local strain at the notch root using elastic-perfectly plastic and bi-linear models. The maximum principal strain and Nonproportional strain ranges conservatively estimated the crack initiation lives of the notched specimens
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evaluation of multiaxial low cycle fatigue life under Nonproportional Loading
ICMFF10, 2015Co-Authors: Takamoto Itoh, Masao SakaneAbstract:A simple and clear method of evaluating stress and strain ranges undernon-proportional multiaxial Loading where principal directions of stress and strain arechanged during a cycle is needed for assessing multiaxial fatigue. This paper presents asimple method of determining the principal stress and strain ranges and the severity ofnon-proportional Loading with defining the rotation angles of the maximum principalstress and strain in a three dimensional stress and strain space. This study alsodiscusses properties of multiaxial low cycle fatigue lives for various materials fatiguedunder non-proportional Loadings and shows an applicability of a parameter proposedby author for multiaxial low cycle fatigue life evaluation.
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high temperature Nonproportional low cycle fatigue using fifteen Loading paths
Theoretical and Applied Fracture Mechanics, 2014Co-Authors: Naomi Hamada, Masao Sakane, Takamoto Itoh, Hideyuki KanayamaAbstract:Abstract This paper discusses effects of Nonproportional Loading on low cycle fatigue lives for Type 304 stainless steel hollow cylinder specimens at 923 K. Strain controlled axial–torsion low cycle fatigue tests were performed using fifteen proportional and Nonproportional strain paths at a strain rate of 0.1%/s. Nonproportional straining significantly reduced fatigue lives of the steel at 923 K. Reduction in fatigue life due to Nonproportional straining reached about 80% compared with the proportional straining in specific strain paths. The Nonproportional strains, ΔɛNP and Δ e NP ∗ , and energy parameter, ΔσIΔɛI, successfully correlated proportional and Nonproportional fatigue lives but ASME equivalent strain gave significantly unconservative estimates.
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Multiaxial low cycle fatigue life of Mod.9Cr-1Mo steel circumferential notched specimen under Nonproportional Loading
Strength Fracture and Complexity, 2011Co-Authors: Taejoon Kim, Yuki Watanabe, Shengde Zhang, Masao SakaneAbstract:This paper presents the notch effect in low cycle fatigue of Mod.9Cr-1Mo steel under multiaxial Loading. Tension- torsion multiaxial low cycle fatigue tests were performed using three types of circumferential notched specimens of the steel and crack initiation, failure and propagation lives were experimentally obtained. Two proportional and nine Nonproportional strain waveforms were used in low cycle fatigue tests. The superposition of torsion Loading on tension Loading reduced the three lives but they little decreased with elastic stress concentration factor. The three lives in Nonproportional Loading were smaller than those in proportional Loading but showed smaller reduction with elastic stress concentration factor. Local strains at the notch root were estimated by finite element analyses and Neuber's rule. Mises strain range and maximum principal strain range conservatively estimated the crack initiation lives of the notched specimens.
Ming Bao - One of the best experts on this subject based on the ideXlab platform.
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multiaxial fatigue damage parameter and life prediction under low cycle Loading for gh4169 alloy and other structural materials
International Journal of Fatigue, 2010Co-Authors: Guoqin Sun, Ming BaoAbstract:Abstract Combined tension–torsion fatigue tests were conducted on nickel-based alloy GH4169 under proportional and Nonproportional Loading at 650 °C. The fatigue cracks on the specimen surface were found basically initiating and propagating along the maximum shear plane. Taking into account the materials in elastic–plastic state under low-cycle fatigue, a multiaxial fatigue damage parameter based on SW model was proposed. The developed damage model can be reduced to the uniaxial Manson–Coffin equation, which was used to evaluate the low cycle multiaxial fatigue for GH4169 alloy, Haynes188 and mild steel. It is concluded that the predicted results with the proposed model can give satisfied results.
Xin Wang - One of the best experts on this subject based on the ideXlab platform.
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the effects of Nonproportional Loading on the elastic plastic crack tip fields
Engineering Fracture Mechanics, 2017Co-Authors: Zhaoyu Jin, Xin Wang, Xu ChenAbstract:Abstract In this paper, the biaxial Loading path effects on the mode I plane strain elastic-plastic crack-tip stress fields are investigated computationally. First, three different Loading sequences including one proportional Loading and two non-proportional Loading paths are applied to the modified boundary layer (MBL) model under small-scale yielding conditions. For the same external displacement field applied at the outer boundary of the MBL model, the mode I K field and T-stress field combined as the different Loading paths are applied to investigate the influence of the Nonproportional Loading. The results show that for either the compressive or tensile T -stress, the Loading path which applied K field first followed by T-stress field generates the lower crack-tip constraint comparing to proportional Loading. There is only minor difference between the results from proportional Loading path and that with the T-stress field applied first following by K field. Next, two finite width specimens under non-proportional biaxial Loading conditions that generate the same three Loading paths are analyzed. Similar crack tip characteristics are observed in these specimens as these obtained from the MBL model, and it is demonstrated that the near-tip behavior in specimens can be predicted accurately using the results from MBL models. The present results show that it is very important to include the load sequence effects in elastic-plastic fracture analysis when dealing with Nonproportional Loading conditions.
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the effects of Nonproportional Loading on the elastic plastic crack fronts fields
ASME 2016 Pressure Vessels and Piping Conference, 2016Co-Authors: Zhaoyu Jin, Xin WangAbstract:In this paper, the Loading path effect on the elastic-plastic crack-front stress field in a thin plate is investigated. There different Loading sequences include one proportional Loading and two non-proportional Loading paths are applied to the 3-D modified boundary layer (MBL) model under small-scale yielding conditions. For the same external displacement field applied at the outer boundary of the 3-D MBL model, the mode I K field and T-stress field combined as the different Loading path is applied to investigate the influence of the Nonproportional Loading. The results show that for either the compressive or tensional T-stress, the Loading path which applied K field followed by T field generates the lower crack-tip constraint. There is only slightly difference between the proportional Loading path and the T-stress field following by K field Loading path. The results show that it is very important to include the load sequence effects in fracture analysis when dealing with Nonproportional Loading conditions.Copyright © 2016 by ASME
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the effects of Nonproportional Loading on the elastic plastic crack tip fields
Applied Mechanics and Materials, 2016Co-Authors: Zhaoyu Jin, Xin Wang, Xu ChenAbstract:In this paper, the Loading path effects on the plane strain elastic-plastic crack-tip stress field are investigated computationally. Three different Loading sequences include one proportional Loading and two non-proportional Loading paths are applied to the modified boundary layer (MBL) model under small-scale yielding conditions. For the same external displacement field applied at the outer boundary of the MBL model, the mode I K field and T-stress field combined as the different Loading paths are applied to investigate the influence of the Nonproportional Loading. The results show that for either the compressive or tensional T-stress, the Loading path which applied K field followed by T field generates the lower crack-tip constraint. There is only slightly difference between the proportional Loading path and that with the T-stress field following by K field. The results show that it is very important to include the load sequence effects in fracture analysis when dealing with Nonproportional Loading conditions.
Weixing Yao - One of the best experts on this subject based on the ideXlab platform.
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a multiaxial fatigue criterion for various metallic materials under proportional and Nonproportional Loading
International Journal of Fatigue, 2006Co-Authors: Yingyu Wang, Weixing YaoAbstract:Abstract Proportional and Nonproportional tension–torsion fatigue tests were conducted on LY12CZ aluminum alloy. Two types of tubular specimens were used, one is smooth and the other is notched. The experimental data are analyzed. A new critical plane criterion including the strain and stress parameters is proposed. The capability of fatigue life prediction for the proposed fatigue damage model is checked against the experimental data of LY12CZ aluminum alloy and two other metals under proportional and Nonproportional Loading, and the predicted results are compared with results from common multiaxial fatigue model. It is demonstrated that the proposed criterion gives better satisfactory results for all the three checked materials.
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evaluation and comparison of several multiaxial fatigue criteria
International Journal of Fatigue, 2004Co-Authors: Yingyu Wang, Weixing YaoAbstract:In this paper several multiaxial fatigue criteria are reviewed. The criteria are divided into three groups, according to the parameters used to describe the fatigue life or fatigue strength of materials. They are stress criteria, strain criteria and energy criteria. Their predictive capabilities are checked against the experimental data of six materials under proportional and Nonproportional Loading. Among the stress criteria, the criterion of Lee is in the best agreement with the test data. Among the strain criteria, the Kandil, Brown and Miller’s criterion has the best correlation with the experimental data of the materials employed. The Farahani’s criterion yields the most satisfactory result among the energy criteria. Its fatigue life correlation for 1045HR steel and 304 stainless steel fell within factors of 2 and 3, respectively. 2003 Elsevier Ltd. All rights reserved.
