Heat-Treatment Temperature Influence on Structure and Magnetic Properties of SrFe11.85Sm0.15O19 Ferrite Nanofiber

2013 ◽  
Vol 575-576 ◽  
pp. 313-316
Author(s):  
Xian Feng Meng ◽  
Yin Bo Hong ◽  
Yong Kang Ji
Keyword(s):  
Heat Treatment ◽  
Magnetic Properties ◽  
High Temperature ◽  
Low Temperature ◽  
Heat Treatment Temperature ◽  
Treatment Temperature ◽  
Temperature Influence ◽  
One Dimensional ◽  
Structure And Morphology ◽  
Calcined Temperature

one-dimensional SrFe11.85Sm0.15O19nanofibers were synthesized by electrospinning combined with heating treatments. This paper involved an investigation of how heat treatment temperature and Sm3+influence structure and morphology of nanofibers. FTIR and XRD results demonstrated that SrFe11.85Sm0.15O19magnetoplumbite phase was formed with increasing of calcined temperature, and small amountα-Fe2O3and SmFeO3were detected at low temperature and high temperature, respectively. The calcined temperature had a great impact on the morphology of nanofibers, which changes from a continuous fibrous structure to large plate grain. The VSM results revealed that the Ms and Hc of nanofiber were both increased with calcined temperature.

Effect of Pre-Weld Heat Treatment Temperatures on TIG Welded Microstructures on Nickel Base Superalloy, GTD-111

2015 ◽  
Vol 658 ◽  
pp. 14-18
Author(s):  
Tanaporn Rojhirunsakool ◽  
Duangkwan Thongpian ◽  
Nutthita Chuankrerkkul ◽  
Panyawat Wangyao
Keyword(s):  
Heat Treatment ◽  
High Temperature ◽  
Heat Treatment Temperature ◽  
Treatment Temperature ◽  
Tig Welding ◽  
Nickel Base Superalloy ◽  
Nickel Base ◽  
Base Superalloy ◽  
Weld Heat

Nickel-base superalloys have been used as high temperature materials in land-base gas turbine application. When subjected to long term, high temperature service, large crack propagation was observed. Typical refurbishment method of these turbines is carried out by using TIG welding followed by post-weld standard heat treatment. However, new crack initiation is found in the heat-affected zone after TIG welding. Pre-weld heat treatment has been discovered to improves final γ + γ’ microstructure. This study focuses on the effect of pre-weld heat treatment temperature on final γ + γ’ microstructure. Seven different conditions of pre-weld heat treatment temperature were investigated. Scanning electron microscopy studies were carried out after pre-weld and post-weld heat treatments to compare the γ + γ’ microstructure and capture microcracks. The best pre-weld heat treatment temperature produces uniform distribution of finely dispersed γ’ precipitates in the γ matrix without post-weld crack.

Low-temperature thermal pretreatment process for recycling inner core of spent lithium iron phosphate batteries

2020 ◽  
pp. 0734242X2095740
Author(s):  
Haijun Bi ◽  
Huabing Zhu ◽  
Lei Zu ◽  
Yong Gao ◽  
Song Gao ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Low Temperature ◽  
Heat Treatment Temperature ◽  
Lithium Iron Phosphate ◽  
Inner Core ◽  
Treatment Time ◽  
Iron Phosphate ◽  
Treatment Temperature ◽  
Heat Treatment Time ◽  
Physicochemical Changes

Spent lithium iron phosphate (LFP) batteries contain abundant strategic lithium resources and are thus considered attractive secondary lithium sources. However, these batteries may contaminate the environment because they contain hazardous materials. In this work, a novel process involving low-temperature heat treatment is used as an alternative pretreatment method for recycling spent LFP batteries. When the temperature reaches 300°C, the dissociation effect of the anode material gradually improves with heat treatment time. At the heat treatment time of 120 minutes, an electrode material can be dissociated. The extension of heat treatment time has a minimal effect on quality loss. The physicochemical changes in thermally treated solid cathode and anode materials are examined through scanning electron microscopy with energy-dispersive X-ray spectroscopy. The heat treatment results in the complete separation of the materials from aluminium foil without contamination. The change in heat treatment temperature has a small effect on the quality of LFP material shedding. When the heat treatment temperature reaches 300°C and the time reaches 120 minutes, heat treatment time increases, and the yield of each particle size is stable and basically unchanged. The method can be scaled up and may reduce environmental pollution due to waste LFP batteries.

scholarly journals Electrical Resistivity of Carbonaceous Bed Material at High Temperature

Processes ◽  
2020 ◽  
Vol 8 (8) ◽  
pp. 933 ◽  
Author(s):  
Gerrit Ralf Surup ◽  
Tommy Andre Pedersen ◽  
Annah Chaldien ◽  
Johan Paul Beukes ◽  
Merete Tangstad
Keyword(s):  
Heat Treatment ◽  
Electrical Resistivity ◽  
High Temperature ◽  
Carbon Source ◽  
Heat Treatment Temperature ◽  
Electric Arc ◽  
Treatment Temperature ◽  
Electric Arc Furnaces ◽  
Arc Furnaces ◽  
Set Up

This study reports the effect of high-temperature treatment on the electrical properties of charcoal, coal, and coke. The electrical resistivity of industrial charcoal samples used as a reducing agent in electric arc furnaces was investigated as a renewable carbon source. A set-up to measure the electrical resistivity of bulk material at heat treatment temperatures up to 1700 ∘C was developed. Results were also evaluated at room temperature by a four-point probe set-up with adjustable load. It is shown that the electrical resistivity of charcoal decreases with increasing heat treatment temperature and approaches the resistivity of fossil carbon materials at temperatures greater than 1400 ∘C. The heat treatment temperature of carbon material is the main influencing parameter, whereas the measurement temperature and residence time showed only a minor effect on electrical resistivity. Bulk density of the carbon material and load on the burden have a large impact on the electrical resistivity of each material, while the effect of particle size can be neglected at high heat treatment temperature or compacting pressure. The mechanical durability of charcoal slightly increased after heat treatment and decreased for coal and semi-coke samples. The results indicate that charcoal can be used as an efficient carbon source for electric arc furnaces.

scholarly journals Influence of heat treatment on LiNbO3 thin films prepared on Si(111) by the polymeric precursor method

1999 ◽  
Vol 14 (7) ◽  
pp. 3115-3121 ◽  
Author(s):  
V. Bouquet ◽  
E. Longo ◽  
E. R. Leite ◽  
J. A. Varela
Keyword(s):  
Thin Films ◽  
Heat Treatment ◽  
High Temperature ◽  
Low Temperature ◽  
Thermal Analyses ◽  
Dip Coating ◽  
Treatment Temperature ◽  
Polymeric Precursor Method ◽  
Polymeric Precursor ◽  
Precursor Method

The effects of heat-treatment temperature on LiNbO3 thin films prepared by the polymeric precursor method were investigated. The precursor solution was deposited on Si(111) substrates by dip coating. X-ray diffraction and thermal analyses revealed that the crystallization process occurred at a low temperature (420 °C) and led to films with no preferential orientation. High-temperature treatments promoted formation of the LiNb3O8 phase. Scanning electron microscopy, coupled with energy dispersive spectroscopy analyses, showed that the treatment temperature also affected the film microstructure. The surface texture—homogeneous, smooth, and pore-free at low temperature—turned into an “islandlike” microstructure for high-temperature treatments.

Phase Transformation of Coal at High Temperature

2014 ◽  
Vol 809-810 ◽  
pp. 815-821
Author(s):  
Xiao Hu Hua ◽  
Xiao Gang Wang ◽  
Jia Qing Yang ◽  
Shu He Lu ◽  
Li Rong Deng ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Phase Transformation ◽  
Phase Composition ◽  
High Temperature ◽  
Internal Migration ◽  
Heat Treatment Temperature ◽  
Functional Group ◽  
Treatment Temperature ◽  
Conductive Phase ◽  
Higher Temperature

Anthracite and bitumite were processed respectively at 1400°C,1700°C, 2000°C, 2200°C, 2400°C and 2600°C,and their chemical composition,resistivity,microstructure, phase composition,and the internal migration of molecular functional group were tested and characterized. The results indicate that moisture, ash and volatile in coal have gradually shifted and lost with the elevation of heat treatment temperature, while the higher temperature, the quicker and completer phase change. Heat treatment can make the coal transform from approximately insulative phase to conductive phase,. Furthermore, as the temperature increases, the conductive phase transformation effect is better. The higher the heat treatment temperature of coal, the more amorphous carbon transforming into crystalline carbon completely, but the less types of phases .

Cement Hydration in the Presence of Nano Magnesium Oxides With Controlled Reactivity

2018 ◽  
Author(s):  
Narjes Jafariesfad ◽  
Pål Skalle ◽  
Mette R. Geiker
Keyword(s):  
Heat Treatment ◽  
Low Temperature ◽  
Induction Period ◽  
Reference System ◽  
Heat Treatment Temperature ◽  
Cement Hydration ◽  
Isothermal Calorimetry ◽  
Treatment Temperature ◽  
Heat Treated ◽  
Cement System

In order to effectively compensate for bulk shrinkage of cement systems, the reaction of expansive additives must be regulated taking into account the development of cement hydration. In this study, nano-MgO particles (NM) with controlled reactivity were added to a cement system. The reactivity of NM was regulated via heat-treatment and the cement systems were investigated using isothermal calorimetry. Our results showed that increase in heat-treatment temperature resulted in coarsening of the NM and retardation of the NM reaction. We demonstrated that the addition of NM, heat-treated at low temperature, to a cement system caused significant reduction in the induction period compared to the reference system without NM. Controlling the reactivity of NMs might be a promising method in designing zero-shrinkage cement systems.

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