3D microstructure evolution of ice in jet A-1 fuel as a function of applied temperature over time

With the 3D thermal mechanical coupled elastic-plastic finite element method and by simulating the whole rolling process of 1250mm×20mm C-Mn hot strips, this paper obtains the temperature field and deformation result of the rolling process. By comparing the temperature drop curve with the measured data in the field, it shows that the simulation result is close to the real situation. Based on the thermal mechanical coupled simulation of the whole rolling process, this paper completes the computational simulation of the prediction of the 3D microstructure and property of hot strips by using the relevant microstructure evolution and property prediction models and advanced C language programming, thus providing reference for the property prediction of new products and processes.

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Evolution of Individual Grains in 3d Microstructure Generated by Computational Simulation of Transformations Involving Two Phases

Materials Science Forum ◽

10.4028/www.scientific.net/msf.930.305 ◽

2018 ◽

Vol 930 ◽

pp. 305-310

Author(s):

André Luiz Moraes Alves ◽

Guilherme Dias da Fonseca ◽

Marcos Felipe Braga da Costa ◽

Weslley Luiz da Silva Assis ◽

Paulo Rangel Rios

Keyword(s):

Mathematical Model ◽

Solid State ◽

Phase Transformations ◽

Microstructure Evolution ◽

Initial Phase ◽

Computational Simulation ◽

3D Microstructure ◽

Phase Transform ◽

Two Phases ◽

Individual Grains

In the phase transformations of the solid state, situations can occur in which the initial phase transform forming two or more distinct phases. The exact mathematical model for situations where more than one transformation occurs simultaneously or sequentially was proposed by Rios and Villa. The computational simulation was used to study the evolution and visualization of the possible microstructures that these transformations may present. The causal cone methodology was adopted. The simulations were compared with the analytical model to ensure that they occur as expected. The growth of individual grains of each phase was monitored in 3D microstructure evolution. With this monitoring, was possible to extract useful data able to quantify the simulated 3D microstructure. Quantifying the simulated microstructures increase the possibility of the simulations give to the experimentalist insights about the transformations. In this paper, it is verified that each grain evolves in an individual way, as expected, however their growth is similar.

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Microstructure and mechanical properties of 3D Cf/SiBCN composites fabricated by polymer infiltration and pyrolysis

10.21203/rs.3.rs-32542/v1 ◽

2020 ◽

Author(s):

Bowen Chen ◽

Qi Ding ◽

De-Wei Ni ◽

Hongda Wang ◽

Yusheng Ding ◽

...

Keyword(s):

Mechanical Properties ◽

Microstructure Evolution ◽

Cross Link ◽

Ceramic Yield ◽

Liquid Precursor ◽

X Ray ◽

3D Microstructure ◽

Crosslinking Process ◽

X Ray Computed ◽

Polymer Infiltration

Abstract In this work, 3D Cf/SiBCN composites were fabricated by polymer infiltration and pyrolysis (PIP) with poly(methylvinyl)borosilazane as SiBCN precursor. The 3D microstructure evolution process of the composites was investigated by an advanced x-ray computed tomography (XCT). The effect of dicumyl peroxide (DCP) initiator addition on the crosslinking process, microstructure evolution and mechanical properties of the composites were uncovered. With the addition of DCP initiator, the liquid precursor can cross-link to solid-state at 120 °C. Moreover, DCP addition decreases the release of small molecule gas during pyrolysis, leading to an improved ceramic yield 4.67 times higher than that without DCP addition. After 7 PIP cycles, density and open porosity of the final Cf/SiBCN composite with DCP addition are 1.73 g·cm-3 and ~10%, respectively, which are 143.0% higher and 30.3% lower compared with the composite without DCP addition. As a result, the flexural strength and elastic modulus of Cf/SiBCN composites with DCP addition (371 MPa and 31 GPa) are 1.74 and 1.60 times higher than that without DCP addition (213 MPa and 19.4 GPa).

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Simulation and experimental comparison of the thermo-mechanical history and 3D microstructure evolution of 304L stainless steel tubes manufactured using LENS

Computational Mechanics ◽

10.1007/s00466-017-1516-y ◽

2017 ◽

Vol 61 (5) ◽

pp. 559-574 ◽

Cited By ~ 22

Author(s):

Kyle L. Johnson ◽

Theron M. Rodgers ◽

Olivia D. Underwood ◽

Jonathan D. Madison ◽

Kurtis R. Ford ◽

...

Keyword(s):

Stainless Steel ◽

Microstructure Evolution ◽

Experimental Comparison ◽

304L Stainless Steel ◽

Steel Tubes ◽

3D Microstructure

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Microstructure and mechanical properties of 3D Cf/SiBCN composites fabricated by polymer infiltration and pyrolysis

Journal of Advanced Ceramics ◽

10.1007/s40145-020-0414-5 ◽

2020 ◽

Author(s):

Bowen Chen ◽

Qi Ding ◽

Dewei Ni ◽

Hongda Wang ◽

Yusheng Ding ◽

...

Keyword(s):

Mechanical Properties ◽

Microstructure Evolution ◽

Three Dimensional ◽

Cross Linking ◽

Ceramic Yield ◽

X Ray ◽

3D Microstructure ◽

Crosslinking Process ◽

X Ray Computed ◽

Polymer Infiltration

AbstractIn this work, three-dimensional (3D) Cf/SiBCN composites were fabricated by polymer infiltration and pyrolysis (PIP) with poly(methylvinyl)borosilazane as SiBCN precursor. The 3D microstructure evolution process of the composites was investigated by an advanced X-ray computed tomography (XCT). The effect of dicumyl peroxide (DCP) initiator addition on the crosslinking process, microstructure evolution, and mechanical properties of the composites were uncovered. With the addition of a DCP initiator, the liquid precursor can cross-linking to solid-state at 120 °C. Moreover, DCP addition decreases the release of small molecule gas during pyrolysis, leading to an improved ceramic yield 4.67 times higher than that without DCP addition. After 7 PIP cycles, density and open porosity of the final Cf/SiBCN composite with DCP addition are 1.73 g·cm−3 and ∼10%, respectively, which are 143.0% higher and 30.3% lower compared with the composites without DCP addition. As a result, the flexural strength and elastic modulus of Cf/SiBCN composites with DCP addition (371 MPa and 31 GPa) are 1.74 and 1.60 times higher than that without DCP addition (213 MPa and 19.4 GPa), respectively.

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Prediction of densification and microstructure evolution for α-Al2O3 during pressureless sintering at low heating rates based on the master sintering curve theory

Science of Sintering ◽

10.2298/sos0803251s ◽

2008 ◽

Vol 40 (3) ◽

pp. 251-261 ◽

Cited By ~ 6

Author(s):

W.Q. Shao ◽

S.O. Chen ◽

D. Li ◽

H.S. Cao ◽

Y.C. Zhang ◽

...

Keyword(s):

Microstructure Evolution ◽

Sintered Density ◽

Heating Rates ◽

Temperature Function ◽

The Mean ◽

Sintering Conditions ◽

Α Al2o3 ◽

And Control ◽

Experimental Runs ◽

Over Time

The master sintering curve (MSC), in which the sintered density is a unique function of the integral of a temperature function over time, is insensitive to the heating path. Densification of ?-Al2O3 with the mean particle size of 2.5?m was continuously recorded during heating at 0.5, 2 and 5oC/min. A MSC was successfully constructed using dilatometry data with the help of a combined-stage sintering model. The validity of the MSC was verified by seveal experimental runs. The microstructural evolution with densification during different heating-rate sintering was explored. The sintered microstructure is a function of the time-temperature sintering conditions, and it is verified that there exists a link between sintered density and microstructure. The MSC can be used to predict and control microstructure evolution during sintering of ?-Al2O3 ceramics.

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Microstructure and mechanical properties of 3D Cf/SiBCN composites fabricated by polymer infiltration and pyrolysis

10.21203/rs.3.rs-32542/v2 ◽

2020 ◽

Author(s):

Bowen Chen ◽

Qi Ding ◽

De-Wei Ni ◽

Hongda Wang ◽

Yusheng Ding ◽

...

Keyword(s):

Mechanical Properties ◽

Microstructure Evolution ◽

Cross Link ◽

Ceramic Yield ◽

Liquid Precursor ◽

X Ray ◽

3D Microstructure ◽

Crosslinking Process ◽

X Ray Computed ◽

Polymer Infiltration

Abstract In this work, 3D C f /SiBCN composites were fabricated by polymer infiltration and pyrolysis (PIP) with poly(methylvinyl)borosilazane as SiBCN precursor. The 3D microstructure evolution process of the composites was investigated by an advanced x-ray computed tomography (XCT). The effect of dicumyl peroxide (DCP) initiator addition on the crosslinking process, microstructure evolution and mechanical properties of the composites were uncovered. With the addition of DCP initiator, the liquid precursor can cross-link to solid-state at 120 °C. Moreover, DCP addition decreases the release of small molecule gas during pyrolysis, leading to an improved ceramic yield 4.67 times higher than that without DCP addition. After 7 PIP cycles, density and open porosity of the final Cf/SiBCN composite with DCP addition are 1.73 g·cm -3 and ~10%, respectively, which are 143.0% higher and 30.3% lower compared with the composites without DCP addition. As a result, the flexural strength and elastic modulus of Cf/SiBCN composites with DCP addition (371 MPa and 31 GPa) are 1.74 and 1.60 times higher than that without DCP addition (213 MPa and 19.4 GPa).

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Social transmission bias and the cultural evolution of folk-economic beliefs

Behavioral and Brain Sciences ◽

10.1017/s0140525x18000365 ◽

2018 ◽

Vol 41 ◽

Cited By ~ 3

Author(s):

David Hirshleifer ◽

Siew Hong Teoh

Keyword(s):

Cultural Evolution ◽

Social Transmission ◽

Cognitive Approach ◽

Economic Problems ◽

Economic Attitudes ◽

The Social ◽

Economic Beliefs ◽

Over Time

AbstractEvolved dispositions influence, but do not determine, how people think about economic problems. The evolutionary cognitive approach offers important insights but underweights the social transmission of ideas as a level of explanation. The need for asocialexplanation for the evolution of economic attitudes is evidenced, for example, by immense variations in folk-economic beliefs over time and across individuals.

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