The characteristics of plastic flow and a physically-based model for 3003 Al–Mn alloy upon a wide range of strain rates and temperatures

This paper is to understand and model the thermomechanical response of the rotary forged WHA, uniaxial compression and tension tests are performed on cylindrical samples, using a material testing machines and the split Hopkinson bar technique. True strains exceeding 40% are achieved in these tests over the range of strain rates from 0.001/s to about 7,000/s, and at initial temperatures from 77K to 1,073K. The results show: 1) the WHA displays a pronounced changing orientation due to mechanical processing, that is, the material is inhomogeneous along the section; 2) the dynamic strain aging occurs at temperatures over 700K and in a strain rate of 10-3 1/s; 3) failure strains decrease with increasing strain rate under uniaxial tension, it is about 1.2% at a strain rate of 1,000 1/s; and 4) flow stress of WHA strongly depends on temperatures and strain rates. Finally, based on the mechanism of dislocation motion, the parameters of a physically-based model are estimated by the experimental results. A good agreement between the modeling prediction and experiments was obtained.

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A Constitutive Model Research Based on Dislocation Mechanism of 5083 Aluminum Alloy

Journal of Mechanics ◽

10.1017/jmech.2017.106 ◽

2017 ◽

Vol 35 (02) ◽

pp. 145-152

Author(s):

N. Gao ◽

Z. Zhu ◽

S. Xiao ◽

Q. Xie

Keyword(s):

Aluminum Alloy ◽

Constitutive Model ◽

Plastic Flow ◽

Test System ◽

Dislocation Dynamics ◽

Strain Rates ◽

Prediction Ability ◽

Yield Behavior ◽

Wide Range ◽

5083 Aluminum Alloy

ABSTRACTThe study of the mechanical properties of polycrystalline alloy materials under dynamic impact, namely, the prediction of mechanical behavior after yield stress and the establishment of a constitutive model, has attracted much attention in the field of engineering. The stress-strain curves of 5083 aluminum alloy were obtained under strain rates varying from 0.0002 s-1 to 7130 s-1 through uniaxial compression experiments. The equipment used included a CRIMS RPL100 tester, Instron tester, and split Hopkinson test system. In addition, based on dislocation dynamics and the strengthening mechanism of metals, the plastic flow of the 5083 aluminum alloy was systematically analyzed under a wide range of strain rates. It was found that the abnormal yield behavior of the 5083 aluminum alloy under a wide range of strain rates increased, and the experimental phenomenon of hardening rate decreased with an increase in strain rate. This study also revealed that the abnormal yield behavior is caused by the different dislocation mechanisms of two-phase alloy elements under different strain rates. Based on the thermal activation theory and the experimental data, a constitutive model was developed. A comparison showed good agreement between the experimental and model curves. This indicates that this model has good plastic flow stress prediction ability for such types of materials.

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Modeling the Hydrologic Cycle: The MC Model

Hydrology Research ◽

10.2166/nh.1985.0020 ◽

1985 ◽

Vol 16 (5) ◽

pp. 257-272 ◽

Cited By ~ 7

Author(s):

J. Deschesnes ◽

J.-P. Villeneuve ◽

E. Ledoux ◽

G. Girard

Keyword(s):

Water Resources ◽

Joint Modeling ◽

Surface Flow ◽

Hydrologic Cycle ◽

Saturated Zone ◽

Physically Based Model ◽

Wide Range ◽

Water Tables ◽

Physically Based ◽

Surface And Groundwater

This article discusses the joint modeling of surface and groundwater flows by presenting and describing the MC model. The purpose of this deterministic physically based model is to simulate the behavior of available water resources for one or many watersheds. The model integrates surface flow, streamflow, flow in the non-saturated zone, groundwater flow and the interactions between rivers and water tables. Its formulation and its structure, especially its nested square meshes of variable sizes, confer a great deal of flexibility to the model; this facilitates adaptation to variable modeling scales and to a wide range of geological, geographical and climatological conditions.

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A physically based model for the isothermal martensitic transformation in a maraging steel

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:2003919 ◽

2003 ◽

Vol 112 ◽

pp. 437-440 ◽

Cited By ~ 1

Author(s):

S. O. Kruijver ◽

H. S. Blaauw ◽

J. Beyer ◽

J. Post

Keyword(s):

Martensitic Transformation ◽

Maraging Steel ◽

Physically Based Model ◽

Physically Based ◽

Isothermal Martensitic Transformation

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A new approach to mapping landslide hazards: a probabilistic integration of empirical and physically based models in the North Cascades of Washington, USA

Natural Hazards and Earth System Science ◽

10.5194/nhess-19-2477-2019 ◽

2019 ◽

Vol 19 (11) ◽

pp. 2477-2495

Author(s):

Ronda Strauch ◽

Erkan Istanbulluoglu ◽

Jon Riedel

Keyword(s):

Statistical Approach ◽

Joint Probability ◽

North Cascades ◽

Physically Based Model ◽

New Approach ◽

The North ◽

Debris Avalanches ◽

Landslide Hazards ◽

Infinite Slope Stability Model ◽

Physically Based

Abstract. We developed a new approach for mapping landslide hazards by combining probabilities of landslide impacts derived from a data-driven statistical approach and a physically based model of shallow landsliding. Our statistical approach integrates the influence of seven site attributes (SAs) on observed landslides using a frequency ratio (FR) method. Influential attributes and resulting susceptibility maps depend on the observations of landslides considered: all types of landslides, debris avalanches only, or source areas of debris avalanches. These observational datasets reflect the detection of different landslide processes or components, which relate to different landslide-inducing factors. For each landslide dataset, a stability index (SI) is calculated as a multiplicative result of the frequency ratios for all attributes and is mapped across our study domain in the North Cascades National Park Complex (NOCA), Washington, USA. A continuous function is developed to relate local SI values to landslide probability based on a ratio of landslide and non-landslide grid cells. The empirical model probability derived from the debris avalanche source area dataset is combined probabilistically with a previously developed physically based probabilistic model. A two-dimensional binning method employs empirical and physically based probabilities as indices and calculates a joint probability of landsliding at the intersections of probability bins. A ratio of the joint probability and the physically based model bin probability is used as a weight to adjust the original physically based probability at each grid cell given empirical evidence. The resulting integrated probability of landslide initiation hazard includes mechanisms not captured by the infinite-slope stability model alone. Improvements in distinguishing potentially unstable areas with the proposed integrated model are statistically quantified. We provide multiple landslide hazard maps that land managers can use for planning and decision-making, as well as for educating the public about hazards from landslides in this remote high-relief terrain.

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