Experimental results and constitutive model of the mechanical behavior of Ti6Al4V alloy at high temperature

The mechanical behavior of plastic material is dramatically sensitive to temperature. An method is proposed to predict the mechanical behavior of plastics for cars, ranging from low-temperature low temperature ≤-40°C to high temperature ≥80°C. It dominates the behavior of plastic material based on improved constitutive model in which the parameters adjusted by a series of tests under different temperatures. The method is validated with test and establishes the basis for research and development of plastic parts for automobile as well.

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A Constitutive Model for the Mechanical Behavior of Single Crystal Silicon at Elevated Temperature

MRS Proceedings ◽

10.1557/proc-687-b9.6 ◽

2001 ◽

Vol 687 ◽

Cited By ~ 5

Author(s):

H.-S. Moon ◽

L. Anand ◽

S. M. Spearing

Keyword(s):

High Temperature ◽

Constitutive Model ◽

Single Crystal ◽

Mechanical Behavior ◽

Elevated Temperatures ◽

Single Crystal Silicon ◽

Operational Environment ◽

Localized Deformation ◽

Creep Tests ◽

Crystal Silicon

AbstractSilicon in single crystal form has been the material of choice for the first demonstration of the MIT microengine project. However, because it has a relatively low melting temperature, silicon is not an ideal material for the intended operational environment of high temperature and stress. In addition, preliminary work indicates that single crystal silicon has a tendency to undergo localized deformation by slip band formation. Thus it is critical to obtain a better understanding of the mechanical behavior of this material at elevated temperatures in order to properly exploit its capabilities as a structural material. Creep tests in simple compression with n-type single crystal silicon, with low initial dislocation density, were conducted over a temperature range of 900 K to 1200 K and a stress range of 10 MPa to 120 MPa. The compression specimens were machined such that the multi-slip <100> or <111> orientations were coincident with the compression axis. The creep tests reveal that response can be delineated into two broad regimes: (a) in the first regime rapid dislocation multiplication is responsible for accelerating creep rates, and (b) in the second regime an increasing resistance to dislocation motion is responsible for the decelerating creep rates, as is typically observed for creep in metals. An isotropic elasto-viscoplastic constitutive model that accounts for these two mechanisms has been developed in support of the design of the high temperature turbine structure of the MIT microengine.

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High‐Temperature Mechanical Behavior Assessment based on a Developed Constitutive Model of Inconel 718 Fabricated by Selective Laser Melting

Advanced Engineering Materials ◽

10.1002/adem.202100232 ◽

2021 ◽

pp. 2100232

Author(s):

Ling Ma ◽

Lei Zhang ◽

Feng Guo ◽

Weiqi Du ◽

Yuanxin Luo

Keyword(s):

High Temperature ◽

Constitutive Model ◽

Mechanical Behavior ◽

Selective Laser Melting ◽

Inconel 718 ◽

Behavior Assessment ◽

Laser Melting

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Dynamic Constitutive Model of Concrete

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.450-451.379 ◽

2012 ◽

Vol 450-451 ◽

pp. 379-382

Author(s):

Wei Wu Yang ◽

Hai Feng Liu ◽

Jian Guo Ning

Keyword(s):

Constitutive Model ◽

Mechanical Behavior ◽

Failure Criterion ◽

Impact Loading ◽

Experimental Results ◽

Dynamic Mechanical ◽

Criterion A ◽

Dynamic Mechanical Behavior ◽

Model Predictions

Based on the damage and Ottosen failure criterion, a dynamic constitutive model is proposed to investigate the mechanical behavior of concrete subjected to impact loading. The model predictions fit well with experimental results. So it can be used to simulate dynamic mechanical behavior of concrete

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Closure Behavior of the Artificial Gas Pore inside the As-Cast Ti6Al4V Alloy during HIP: Constitutive Modeling and Numerical Simulation

Metals ◽

10.3390/met11101598 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1598

Author(s):

Qian Xu ◽

Wen Li ◽

Yajun Yin ◽

Jianxin Zhou

Keyword(s):

Constitutive Model ◽

Constitutive Modeling ◽

Hot Isostatic Pressing ◽

Strain Rate Range ◽

Ti6al4v Alloy ◽

Experimental Results ◽

Raw Material ◽

Compression Tests ◽

Second Stage ◽

Wire Cutting

The isothermal compression tests of as-cast Ti6Al4V alloy specimens, with coarse grains obtained from the runner, were conducted at a strain rate range of 0.001–0.1 s−1 and a temperature range of 710–920 °C. The experimental results were used for constitutive modeling. A hyperbolic sine constitutive model was developed to predict the flow behaviors of the as-cast Ti6Al4V alloy. The experimental results agreed well with the predicted results by the above constitutive model. After the establishment of the constitutive model, the closure behavior of the gas pore inside the as-cast Ti6Al4V alloy during hot isostatic pressing (HIP) was studied by experiment and simulation. Through wire cutting, turning, drilling, and argon arc welding of the raw material, the HIP samples were obtained, with these being a cylindrical specimen (Φ15 mm × 13 mm) with a sealed pore (Φ2.5 mm × 4 mm) inside. Interrupted HIP experiments at 780 °C/102 MPa/0 min and 920 °C/120 MPa/20 min were designed, and a full-standard HIP experiment (920 °C/120 MPa/150 min) was also carried out. The HIP sample was simultaneously numerically simulated using the above constitutive model under the same conditions as the experiment. The simulation and the experimental results revealed that the pore begins to close in the first stage of HIP, and the closing rate is faster than in the second stage of HIP. The gas pore cannot be completely annihilated in a standard HIP cycle. Plastic deformation is the main mechanism for pore closure during HIP.

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Application of TEM to Deformation, Wear, and Fracture of Ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052377 ◽

1974 ◽

Vol 32 ◽

pp. 472-473

Author(s):

B. J. Hockey

Keyword(s):

Wear Resistance ◽

High Temperature ◽

Mechanical Behavior ◽

Brittle Materials ◽

High Temperature Strength ◽

Wide Range ◽

Corrosive Environments ◽

Further Development

Ceramics, such as Al2O3 and SiC have numerous current and potential uses in applications where high temperature strength, hardness, and wear resistance are required often in corrosive environments. These materials are, however, highly anisotropic and brittle, so that their mechanical behavior is often unpredictable. The further development of these materials will require a better understanding of the basic mechanisms controlling deformation, wear, and fracture.The purpose of this talk is to describe applications of TEM to the study of the deformation, wear, and fracture of Al2O3. Similar studies are currently being conducted on SiC and the techniques involved should be applicable to a wide range of hard, brittle materials.

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