Post heat treatment time induced distinguished superconducting features of JR Nb3Al wires rapidly heated around the Tc peak condition

2019 ◽  
Vol 110 ◽  
pp. 106482 ◽  
Author(s):  
Changkun Yang ◽  
Xiaguang Sun ◽  
Pingyuan Li ◽  
Zhou Yu ◽  
Yongliang Chen ◽  
...  
2013 ◽  
Vol 773-774 ◽  
pp. 785-794
Author(s):  
Amir Mahmoudi ◽  
Mohammad Esmailian ◽  
Seyed Eshagh Aghamiri

In this investigation, AISI321 steel was solution - stabilizing post heat treated in various temperatures and times after SMAW welding. Results show, increasing of temperature in solution and stabilizing heat treatment, raise sensitization; in addition, by increasing of the solution heat treatment time, sensitization enhances. However, increasing the time of stabilizing heat treatment creates less chrome carbides, so the sensitization decreases. These heat treatments reduce the amount of delta ferrite and change its morphology from narrow and acicular shape to discontinues and separate globular particles. Moreover, more carbide and carbonitrid of Ti and Nb are also created.


2000 ◽  
Vol 9 (1) ◽  
pp. 72-80
Author(s):  
S. Jahanian ◽  
R.R. Kunde ◽  
P.V. Kuppa

2020 ◽  
pp. 0734242X2095740
Author(s):  
Haijun Bi ◽  
Huabing Zhu ◽  
Lei Zu ◽  
Yong Gao ◽  
Song Gao ◽  
...  

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.


2018 ◽  
Vol 917 ◽  
pp. 64-68
Author(s):  
Wiendartun ◽  
Jaenudin Kamal ◽  
Dadi Rusdiana ◽  
Andhy Setiawan ◽  
Dani Gustaman Syarief

A study on the effect of heat treatment condition on the characteristics of MnO2 added-Fe2TiO5 ceramics for NTC thermistor has been carried out. The ceramics were produced by pressing an homogenous mixture of Fe2O3 (local/ yarosite), TiO2 and MnO2 (2.0 mole %) powders in appropriate proportions to produce Fe2TiO5 based ceramics and sintering the pressed powder at 1050 °C for 3 hours in oxygen gas. Some sintered pellets were heat treated by heating them at 300 °C for 5, 15 and 25 minutes in Ar + 7% H2 gas. The XRD analyses showed that the Fe2TiO5 ceramics with and without heat treatment time had orthorhombic structure. No peak from second phase was observed from the XRD profiles. From the electrical characteristics data, it was known that the heat treatment could change the electrical characteristics of the Fe2TiO5 based-thermistor. The thermistor constant (B) and room temperature resistivity (ρRT) decreased with the increasing of heat treatment time. All ceramics made had thermistor characteristics namely B = 3459-7596 K and ρRT = 1.056-6936.062 MΩcm. Thermistor constant of the ceramics was relatively big, indicated that ceramics made from local iron oxide in this work fit the market requirement for NTC thermistor.


Author(s):  
Shouyu Zhang ◽  
Junfu Lu ◽  
Jianmin Zhang ◽  
Qing Liu ◽  
Guangxi Yue

The effect of heat treatment on the reactivity and crystallinity of char prepared from the vitrinite of two coals (YX, JJ) was investigated by using XRD and TGA in this paper. The results from TGA show that the reactivity of the chars from YXV and JJV decreases with the increase of heat treatment temperature. The reactivity of YXV char decreases quickly and significantly as heat treatment time increases. However, after heat treatment time of 60 min, it decreases slowly. The effect of heat treatment time on the reactivity of JJV char is small. The results from XRD show that the crystallinity of coal-char is determined by the intensity of heat treatment. When heat treatment time is more than 60 minutes, the turbostratic crystallite of YXV char prepared under 900°C changes remarkably and becomes more orderly. The aromatic layer stacking heights (Lc) of YXV Char when heat treated above 900°C increased with the increase of heat treatment time. The effect of heat treat time on Lc of JJV char is small, but under heat treatment temperature of 1200°C, the crystalline of JJV char grows distinctly. There is a good parallel relationship between the crystalline growth and deactivation of the chars. It can be concluded that the growth of the crystalline is the main reason for the deactivation of coal-char.


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