Dendrite Grow up Relations with Cooling Speed

Using confocal laser microscope with an infrared heater for 45 steel under different rate of solidification dendrite formation in the process of in situ observation, in the melt solidification phase has different cooling rate the cooling of dendrite formation, analysis of cooling rate on final solidified structure. Results show that with the reduction of temperature in the solidification process dendrite growth continuously, new nuclear has been formed, with the speeding up of the cooling rate, the dendritic structure refinement.

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Study on Process of SPHC Steel Solidification

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.750-752.385 ◽

2013 ◽

Vol 750-752 ◽

pp. 385-388

Author(s):

Xue Gang Ma ◽

Yuan Liang Li ◽

Rong Li Sang ◽

Yi Shen

Keyword(s):

Laser Scanning ◽

Dendritic Structure ◽

Solidification Process ◽

Laser Scanning Microscopy ◽

Solidification Structure ◽

Confocal Laser ◽

In Situ Observation ◽

Structure Changes ◽

Sphc Steel

Confocal Laser Scanning Microscopy in situ observation of the solidification process of SPHC Steel and SPHC steel solidification structure changes. The results showed that: SPHC steel in the molten state, the surface of the melt flow of black substance; and with the temperature decreasing, SPHC gradually solidified dendrites continue to grow, increasing new nuclear the dendritic structure continue to refine, to δ-Fe and γ-Fe crystalline phase from the melt.

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A Study on the Effect of Alumina on the Morphology and Reduction Behavior of Sinter by In Situ Observation

Metals ◽

10.3390/met11050740 ◽

2021 ◽

Vol 11 (5) ◽

pp. 740

Author(s):

Sang Gyun Shin ◽

Wan Ho Kim ◽

Dong Joon Min

Keyword(s):

Reduction Rate ◽

Al2o3 Content ◽

Confocal Laser ◽

In Situ Observation ◽

Sintering Process ◽

Reduction Behavior ◽

Reducing Gas ◽

Interfacial Chemical Reaction ◽

Reaction Routes

The effects of Al2O3 content on the morphology and reducibility of sinter were respectively investigated using confocal laser microscopy and thermogravimetric analysis at 1273 K under CO gas. To understand the effects of the sintering process, separate samples were prepared via the equilibrium and metastable reaction routes. In the equilibrium samples, the addition of Al2O3 led to the formation of the silico-ferrite of calcium and alumino phase and a decrease in the reduction rate due to the lowered reactivity of iron oxide. In contrast, in the metastable samples, the reduction rate increased after the addition of 2.5 mass% Al2O3. The addition of Al2O3 decreased the fraction of the liquid phase and increased the fraction of pores in the sample. As a result, the reduction rate is proportional to the Al2O3 content owing to the changes in the sinter morphology. In determining the reduction rate of the sinter, the influence of the microstructure on the diffusion of the reducing gas is more significant than that of the interfacial chemical reaction due to the formation of the SFCA phase. The microstructure changes of the sinter with the addition of Al2O3 and the corresponding reduction behaviors are further discussed.

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Analysis on phase nucleation in Sn-Ni peritectic alloy combining confocal laser scanning in-situ observation and differential scanning calorimetry

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.163037 ◽

2021 ◽

pp. 163037

Author(s):

Peng Peng ◽

Weiqi Chen ◽

Yuanli Xu ◽

Xudong Zhang ◽

Yuandong Li ◽

...

Keyword(s):

Differential Scanning Calorimetry ◽

Laser Scanning ◽

Confocal Laser Scanning ◽

Confocal Laser ◽

In Situ Observation ◽

Scanning Calorimetry ◽

Peritectic Alloy ◽

Phase Nucleation

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Study of the Effect of Carbon on the Contraction of Hypo-Peritectic Steels during Initial Solidification by Surface Roughness

Metals ◽

10.3390/met8120982 ◽

2018 ◽

Vol 8 (12) ◽

pp. 982 ◽

Cited By ~ 1

Author(s):

Dazhi Pu ◽

Guanghua Wen ◽

Dachao Fu ◽

Ping Tang ◽

Junli Guo

Keyword(s):

Surface Roughness ◽

Cooling Rate ◽

Solidification Process ◽

Casting Process ◽

Continuous Casting Process ◽

Peritectic Steel ◽

Laser Confocal Microscope ◽

Initial Solidification

In the continuous casting process, the shrinkage of the peritectic phase transition during the initial solidification process has an important influence on the surface quality of peritectic steel. The initial solidification process of 0.10C%, 0.14C%, and 0.16C% peritectic steels was observed in situ by a high temperature laser confocal microscope, and the contraction degree during initial solidification was characterized by surface roughness. The results showed that under the cooling rate of 20 °C/s, the surface roughness value Ra(δ/γ) of 0.10C% peritectic steel was 32 μm, the Ra(δ/γ) value of 0.14C% peritectic steel was 25 μm, and the Ra(δ/γ) value of 0.16C% peritectic steel was 17 μm. With increasing carbon content, the contraction degree of the δ→γ transformation decreased, and the value of the surface roughness Ra(δ/γ) declined. Therefore, surface roughness can characterize the contraction degree of the δ→γ transformation in the initial solidification process of peritectic steel under the condition of a large cooling rate.

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