A unified thermal-hardening and thermal-softening constitutive model of soils

Development of a dynamic constitutive model with particle damage and thermal softening for Al/SiCp composites

Composite Structures ◽

10.1016/j.compstruct.2020.111856 ◽

2020 ◽

Vol 236 ◽

pp. 111856 ◽

Cited By ~ 2

Author(s):

Wei Sun ◽

Chunzheng Duan ◽

Wendian Yin

Keyword(s):

Constitutive Model ◽

Thermal Softening ◽

Particle Damage

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Rate-Dependent Transition From Thermal Softening to Hardening in Elastomers

Journal of Applied Mechanics ◽

10.1115/1.1571860 ◽

2003 ◽

Vol 70 (4) ◽

pp. 611-612 ◽

Cited By ~ 4

Author(s):

Z. Chen ◽

J. L. Atwood ◽

Y.-W. Mai

Keyword(s):

Mechanical Properties ◽

Material Properties ◽

Thermal Softening ◽

Thermal Hardening ◽

Interesting Phenomenon ◽

Entropic Elasticity ◽

Viscoelastic Models ◽

Rate Dependent ◽

Thermal Mechanical Properties ◽

Packaging Industry

The thermal-mechanical properties of the materials currently used in packaging are being reexamined as the electronic packaging industry moves towards chip scale packages and wafer scale packages. The rate-dependent transition of elastic modulus and viscosity from thermal softening to thermal hardening with rising temperature, which does not involve any phase change, has been observed in certain elastomers. An explanation about this interesting phenomenon is given based on thermodynamic considerations. A theoretical analysis is performed to show the limitation of existing viscoelastic models in predicting the transition. It appears that macroscopic material properties should be reexamined based on the physics behind the interaction between ordinary elasticity and entropic elasticity.

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A Constitutive Model of High-Early-Strength Cement with Perlite Powder as a Thermal-Insulating Material Confined by Caron Fiber Reinforced Plastics at Elevated Temperatures

Polymers ◽

10.3390/polym12102369 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2369

Author(s):

Yeou-Fong Li ◽

Wai-Keong Sio ◽

Tzu-Hsien Yang ◽

Ying-Kuan Tsai

Keyword(s):

Compressive Strength ◽

Elevated Temperature ◽

Constitutive Model ◽

Thermal Softening ◽

Insulating Materials ◽

Insulating Material ◽

Thermal Insulating ◽

Softening Parameter ◽

Maximum Compressive Strength ◽

Early Strength

A parabolic stress–strain constitutive model for inorganic thermal-insulating material confined by carbon fiber-reinforced polymer (CFRP) exposed to a surrounding elevated temperature was proposed in this paper. The thermal-insulating material used in this study was composed of high-early-strength cement (HESC) and perlite powder. The compression strengths of four kinds of perlite powder composition ratios of thermal-insulating materials cylindrical specimens which were confined by one, two, and three-layer CFRP composite materials were acquired. The experimental results showed that the compression strength was enhanced as the amount of perlite substitute decreased or as the number of CFRP wrapping layers increased. The Mohr–Columb failure criteria were adopted to predict the maximum compressive strength of CFRP-confined inorganic thermal-insulating material. The strain at the maximum compressive strength was found from the experimental results, and the corresponding axial strain at the maximum compressive strength in the constitutive model was determined from the regression analysis. Furthermore, the compressive strengths of the four different perlite composites of thermal-insulating materials were obtained when heating the specimens from ambient temperature to 300 °C. The compressive strength decreased with an increase in temperature, and a thermal softening parameter model was proposed; the thermal softening parameter was determined from the experimental maximum compressive strength at an elevated temperature. Combining the above two models, the constitutive model of HESC with perlite powder additive as a thermal-insulating material confined by CFRP under elevated temperature was proposed.

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