scholarly journals Simulation of the Peritectic Phase Transition in Fe-C Alloys

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 537
Author(s):  
Hui Fang ◽  
Qianyu Tang ◽  
Qingyu Zhang ◽  
Yiming Fan ◽  
Shiyan Pan ◽  
...  
Keyword(s):  
Phase Transition ◽  
Microstructural Evolution ◽  
Peritectic Transformation ◽  
Experimental Conditions ◽  
Cooling Rates ◽  
Interface Growth ◽  
Δ Ferrite ◽  
Δ Phase ◽  
Ca Model ◽  
High Cooling Rates

In this work, a multi-phase cellular automaton (CA) model is extended for the quantitative simulation of peritectic phase transition. First, the effects of cooling rate/supersaturation and temperature on the peritectic transformation kinetics in Fe-C alloys are investigated by utilizing the present CA model. The CA simulations show that supersaturations in the parent phases (liquid and δ-ferrite) increase the L/γ interface growth velocity remarkably, but tinily for the δ/γ interface migration velocity. There exists a transition supersaturation for isothermal transformations, at which the growth rates of the two interfaces are equal. The transition supersaturation is found to increase with decreasing temperature. Microstructural evolution at different cooling rates during peritectic transformation is simulated using the experimental conditions. At low cooling rates, the δ/γ interface propagates at a higher velocity than the L/γ interface. At high cooling rates, however, the γ-phase grows more into the L-phase with a cellular morphology. Then, the proposed CA model is applied to simulate the microstructural evolution during peritectic reaction. It is observed that the γ-phase propagates along the L/δ interface and finally encircles the δ-phase. Meanwhile, the intervenient γ-phase grows in thickness through peritectic transformation. The CA simulations are compared reasonably well with the experimental data and analytical calculations.

Kinetics of the γ–δ phase transition in energetic nitramine-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine

2019 ◽  
Vol 150 (6) ◽  
pp. 064705 ◽  
Author(s):  
P. Bowlan ◽  
B. F. Henson ◽  
L. Smilowitz ◽  
V. I. Levitas ◽  
N. Suvorova ◽  
...  
Keyword(s):  
Phase Transition ◽  
Δ Phase ◽  
Kinetics Of

The effects of morphology of ferrite and non-metallic inclusions on corrosion behaviour of as-cast 304 stainless steel

CORROSION ◽  
10.5006/3763 ◽  
2021 ◽  
Author(s):  
Danbin Jia ◽  
Liangcai Zhong ◽  
Jingkun Yu ◽  
Zhaoyang Liu ◽  
Yuting Zhou ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Corrosion Behaviour ◽  
Solidification Process ◽  
Inclusion Size ◽  
304 Stainless Steel ◽  
Experimental Conditions ◽  
Quenching Temperature ◽  
Δ Ferrite ◽  
Metallic Inclusions

The effects of morphology of ferrite and non-metallic inclusions on corrosion resistance of as-cast 304 stainless steel (304 SS) were investigated. With the decrease in quenching temperature from 1723 K to 1648 K, the different microstructures of the as-cast 304 SS were obtained as the following series: austenitic-lathy δ ferrite, austenitic-colony δ ferrite and austenitic-blocky δ ferrite, and the average inclusion size increased. The electrochemical results show that the sample with the microstructure of austenitic- lathy δ ferrite and smaller size inclusions had a higher corrosion tendency and the lower pitting resistance. Furthermore, the effect of morphology and content of ferrite on corrosion resistance was greater than that of inclusion size under the current experimental conditions. Therefore, a promising method was developed to improve the corrosion resistance of as-cast 304 SS by changing the solidification process.

Microstructure evolution and plastic deformation of Ni47Co53 alloy under tension

CrystEngComm ◽  
2022 ◽  
Author(s):  
ruibo ma ◽  
Lili Zhou ◽  
Yong-Chao Liang ◽  
Ze-an Tian ◽  
Yun-Fei Mo ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Plastic Deformation ◽  
Rapid Solidification ◽  
Microstructural Evolution ◽  
Microstructure Evolution ◽  
Cooling Rates ◽  
Solidification Processes ◽  
Molecular Dynamics Methods

To investigate microstructural evolution and plastic deformation under tension conditions, the rapid solidification processes of Ni47Co53 alloy are first simulated by molecular dynamics methods at cooling rates of 1011, 1012...

Microstructural evolution and mechanical characterization for the A508–3 steel before and after phase transition

2017 ◽  
Vol 495 ◽  
pp. 103-110 ◽  
Author(s):  
Chuanyang Lu ◽  
Yanming He ◽  
Zengliang Gao ◽  
Jianguo Yang ◽  
Weiya Jin ◽  
...  
Keyword(s):  
Phase Transition ◽  
Microstructural Evolution ◽  
Mechanical Characterization ◽  
Before And After

scholarly journals Effects of deformation on the microstructure of a Ti-V microalloyed steel in the phase transition region

2004 ◽  
Vol 57 (4) ◽  
pp. 303-311
Author(s):  
Wiliam Regone ◽  
Sérgio Tonini Button
Keyword(s):  
Phase Transition ◽  
Phase Transformation ◽  
Transition Region ◽  
Microstructural Evolution ◽  
Microalloyed Steel ◽  
Hot Forging ◽  
Microalloyed Steels ◽  
Air Cooling ◽  
Water Cooling ◽  
Phase Transition Region

Microalloyed steels are used in the forging of many automotive parts like crankshafts and connecting rods. They are hot worked in a sequence of stages that includes the heating to the soaking temperature, followed by forging steps, and finally the controlled cooling to define the microstructure and mechanical properties. In this work it was investigated the thermomechanical behavior and the microstructural evolution of a Ti-V microalloyed steel in the phase transition region. Torsion tests were done with multiple steps with true strain equal to 0.26 in each step. After each torsion step the samples were continuous cooled for 15 seconds to simulate hot forging conditions. These tests provided results for the temperature at the beginning of the phase transformation, and allowed to analyze the microstructural changes. Also, workability tests were held to analyze the microstructural evolution by optical and scanning electron microscopy. Results from the torsion tests showed that the temperature for the beginning of phase transformation is about 700 ºC. Workability tests held at 700 ºC followed by water-cooling presented microstructures with different regions: strain hardened, and static and dynamic recrystallized. Workability tests at 700 ºC followed by air-cooling showed a complex microstructure with ferrite, bainite and martensite, while tests at 650 and 600 ºC followed by water-cooling showed a microstructure with allotriomorphic ferrite present in the grain boundaries of the previous austenite.

Crystallization of ethylene–octene copolymers at high cooling rates

Polymer ◽  
1999 ◽  
Vol 40 (16) ◽  
pp. 4717-4721 ◽  
Author(s):  
J Wagner ◽  
S Abu-Iqyas ◽  
K Monar ◽  
P.J Phillips
Keyword(s):  
Cooling Rates ◽  
High Cooling Rates

scholarly journals Non-Isothermal Crystallisation Kinetics of Polypropylene at High Cooling Rates and Comparison to the Continuous Two-Domain pvT Model

Polymers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1515
Author(s):  
Jonathan Alms ◽  
Christian Hopmann ◽  
Jian Wang ◽  
Tobias Hohlweck
Keyword(s):  
Injection Moulding ◽  
Polymer Processing ◽  
Nucleation And Growth ◽  
Growth Theory ◽  
Crystallisation Kinetics ◽  
Cooling Rates ◽  
Dsc Measurements ◽  
Wide Range ◽  
High Cooling Rates ◽  
Kinetics Of

The modelling of the correlation between pressure, specific volume and temperature (pvT) of polymers is highly important for applications in the polymer processing of semi-crystalline thermoplastics, especially in injection moulding. In injection moulding, the polymer experiences a wide range of cooling rates, for example, 60 °C/min near the centre of the part and up to 3000 °C/min near the mould walls. The cooling rate has a high influence on the pvT behaviour, as was shown in the continuous two-domain pvT model (CTD). This work examined the Hoffman–Lauritzen nucleation and growth theory used in the modified Hammami model for extremely high cooling rates (up to 300,000 °C/min) by means of Flash differential scanning calorimeter (DSC) measurements. The results were compared to those of the empirical continuous two-domain pvT model. It is shown that the Hammami model is not suitable to predict the crystallisation kinetics of polypropylene at cooling rates above 600 °C/min, but that the continuous two-domain pvT model is well able to predict crystallisation temperatures at high cooling rates.

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