A sintering burden blending model based on one-step optimization method and high-temperature characteristics of iron ore

2019 ◽  
Vol 116 (2) ◽  
pp. 211
Author(s):  
Shengli Wu ◽  
Xiaobo Zhai ◽  
Tiankai Song
Keyword(s):  
High Temperature ◽  
Iron Ore ◽  
Intelligent System ◽  
Quantitative Relationship ◽  
High Strength ◽  
Optimization Method ◽  
Temperature Characteristics ◽  
Positive Effects ◽  
One Step ◽  
The One

A sintering burden blending model is an intelligent system used to obtain the optimal blending proportions of burdens with minimal sintering burden cost. In this study, micro-sintering and sinter pot tests were first carried out to clarify the quantitative relationship between the shatter index (SI) of the sinter and high-temperature characteristics (HTCs) of the ore blends. The result shows that the lowest assimilation temperature (LAT) plays a dual role in SI, whereas the index of liquid phase fluidity (ILF) and compressive strength of the bonding phase (CSB) have positive effects on SI. The effect of the ILF is the largest. Based on the one-step optimization method, suitable ranges of room-temperature characteristics (RTCs) of ore blends, obtained relationship between sinter strength and HTCs of ore blends, sintering theory, and bisection and simplex algorithms, the proposed sintering burden blending model is established. The validation for the model shows that it is effective at utilizing iron ore resources, maintaining high strength of the sinter, while reducing burden costs.

Improving the Mechanical Properties of AZ31 Mg Alloy by High Ratio Extrusion

2006 ◽  
Vol 503-504 ◽  
pp. 865-870 ◽  
Author(s):  
Yongjun Chen ◽  
Qu Dong Wang ◽  
Jianguo Peng ◽  
Chun Quan Zhai
Keyword(s):  
Mechanical Properties ◽  
High Strength ◽  
High Ratio ◽  
Extrusion Ratio ◽  
Mg Alloy ◽  
Fine Grained ◽  
Az31 Mg Alloy ◽  
Industry Applications ◽  
One Step ◽  
The One

Experiments were conducted both to evaluate the potential for grain refinement, the subsequent mechanical properties at room temperature in samples of AZ31 Mg alloy and also to investigate the relationship between one-step and two-step high ratio extrusion (HRE). The one-step HRE was undertaken using a high extrusion ratio of 70:1 at 250, 300 and 350°C. And the two-step HRE was conducted with an extrusion ratio of 7 for the first step at 250, 300 and 350°C, followed by a second-step extrusion with an extrusion ratio of 10 at 250, 300 and 350°C. The initial grain size in the AZ31 ingot was 100μm and that after one-step HRE became similar to 5μm, after two-step HRE at 250, 300 and 350°C were 2, 4, 7μm, respectively, resulting in superior mechanical properties at ambient temperature. The microstructure of two-step HRE was finer and uniformer than that of one-step HRE and the strength of one-step and two-step HRE were similar, moreover, the elongation of one-step HRE was improved markedly than that of two-step HRE. Dynamic recrystallization and adjacent grain broking during HRE is introduced to explain the effects of one-step and two-step HRE on the microstructure and mechanical properties of AZ31 Mg alloy. The current results imply that the simple HRE method might be a feasible processing method for industry applications, and the multiply steps extrusion are effective to fabricate high strength of fine grained hcp metals.

scholarly journals Improving High-Alumina Iron Ores Processing via the Investigation of the Influence of Alumina Concentration and Type on High-Temperature Characteristics

Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 802
Author(s):  
Yuxiao Xue ◽  
Jian Pan ◽  
Deqing Zhu ◽  
Zhengqi Guo ◽  
Congcong Yang ◽  
...  
Keyword(s):  
High Temperature ◽  
Liquid Phase ◽  
High Strength ◽  
Free State ◽  
High Alumina ◽  
Iron Ores ◽  
Alumina Concentration ◽  
Temperature Characteristics ◽  
Al2o3 Concentration ◽  
Iron Grade

Aiming at the effective utilization of the abundant high-alumina iron ores with low iron grade, the influence of alumina concentration and type on high-temperature characteristics was clarified based on the analyses of eight typical iron ores. The results indicate that high-temperature characteristics of iron ores in various alumina types are different. Higher Al2O3 concentration is deleterious to assimilability and liquid phase fluidity, but the influence extent of each alumina type is substantially different. Kaolinite (Al2O3·2SiO2·2H2O) contributes to correspondingly better assimilability, followed by hercynite (Fe(Fe, Al)2O4), gibbsite (Al(OH)3), diaspore (AlO(OH)), and free state alumina (Al2O3) in turn. Diaspore promotes relatively higher liquid phase fluidity, followed by kaolinite, free state alumina, and hercynite, while gibbsite possesses the maximum adverse impact. Kaolinite and hercynite are more beneficial to form dendritic or acicular silico-ferrite of calcium and alumina (SFCA) with high strength due to the better reactivity, and gibbsite and diaspore lead to more formation of relatively lower strength lamellar or tabular SFCA, while free state alumina is preferable to form disseminated SCFA with rather poorer strength. Kaolinite and hercynite are the most desirable alumina types for sintering rather than free state alumina.

Determination method of high-temperature characteristics of iron-ore sintering based on n(Fe2O3)/n(CaO)

2019 ◽  
Vol 26 (12) ◽  
pp. 1257-1264
Author(s):  
Zheng-wei Yu ◽  
Li-xin Qian ◽  
Hong-ming Long ◽  
Yi-fan Wang ◽  
Qing-min Meng ◽  
...  
Keyword(s):  
High Temperature ◽  
Iron Ore ◽  
Determination Method ◽  
Temperature Characteristics ◽  
Iron Ore Sintering ◽  
Ore Sintering

One-step electrocatalytic synthesis of ammonia and acetone from nitrogen and isopropanol in an ionic liquid

2021 ◽  
Author(s):  
Qikun Zhang ◽  
Ya'nan Zhao ◽  
Liping Yu ◽  
Xiaoyang Zhang ◽  
Yiling Bei ◽  
...  
Keyword(s):  
High Pressure ◽  
Ionic Liquid ◽  
High Temperature ◽  
Synthesis Method ◽  
Environmentally Friendly ◽  
Ambient Conditions ◽  
One Step ◽  
The One

Electrocatalysis is an environmentally friendly synthesis method that overcomes thermodynamic limitations and enables some reactions usually requiring high temperature and high pressure to be realized under ambient conditions. The one-step...

scholarly journals Enhancement of Solvent Resistance of Polyimide Electrospun Mat via the UV-Assisted Electrospinning and Photosensitive Varnish

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2055 ◽  
Author(s):  
Lin Qi ◽  
Chen-Yu Guo ◽  
Meng-Ge Huang Fu ◽  
Yan Zhang ◽  
Lu-meng Yin ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Uv Irradiation ◽  
Starting Material ◽  
Current Work ◽  
Mercury Lamp ◽  
Solvent Resistance ◽  
One Step ◽  
The One

A new methodology for enhancing the solvent resistance of electrospun polyimide (PI) ultrafine fibrous mat (UFM) was investigated in the current work. For this purpose, a negative intrinsically photosensitive polyimide (PSPI) resin was prepared by the one-step high- temperature polycondensation procedure from 3,3’,4,4’-benzophenonetetracarboxylic dianhydride (BTDA) and α,α-bis(4-amino-3,5-dimethylphenyl)phenylmethane (PTMDA). The PI varnish, by dissolving the derived PI (BTDA-PTMDA) resin in N,N-dimethylacetamide (DMAc) at a solid of 20 wt %, was used as the starting material for the standard electrospinning (ES) and ultraviolet-assisted ES (UVAES) fabrications, respectively. The 365 nm wavelength of the high-pressure mercury lamp ultraviolet (UV) irradiation induced the photocrosslinking reaction in the PSPI mat. Solubility tests indicated that the PI UFM fabricated by standard ES procedure showed poor DMAc resistance, while the one by UVAES (PI-UV) exhibited excellent resistance to DMAc.

High Temperature Mechanical Properties of Ti(C,N)-Co-Mo2C Cermets

2009 ◽  
Vol 423 ◽  
pp. 83-88 ◽  
Author(s):  
Angela Gallardo-López ◽  
A. Morales-Rodríguez ◽  
Arturo Domínguez-Rodríguez ◽  
J.M. Córdoba ◽  
M.A. Avilés ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Temperature ◽  
Inert Atmosphere ◽  
Plastic Behavior ◽  
Compression Tests ◽  
Creep Tests ◽  
Temperature Oxidation ◽  
High Temperature Mechanical Properties ◽  
One Step ◽  
The One

The creep behavior of a TiCxN1-x-Co-Mo2C cermet has been investigated at temperatures between 1100-1200°C in an inert atmosphere to assess the one step mechanically induced self-sustaining reaction synthesis and pressureless sintering process, and the influence of the Mo2C additive in the high temperature mechanical properties of this cermet. The samples deform plastically at the chosen temperatures, and values of the stress exponent (n=1.70.6) and activation energy (Q= 4.30.5 eV) have been estimated from uniaxial compression tests. No significant grain growth has been detected after deformation. The reproducibility of the creep tests compared to other compositions indicates that the Mo2C addition contributes to increase notably the resistance to high temperature oxidation of the samples, so that the plastic behavior is not affected by oxidation when deformation experiments are performed in an inert atmosphere.

Research on Ore-Proportioning Optimization Technology in Sintering

2011 ◽  
Vol 117-119 ◽  
pp. 980-983 ◽  
Author(s):  
Xiao Fang Lv ◽  
Hong Liang Han ◽  
Sheng Li Wu
Keyword(s):  
High Temperature ◽  
Chemical Composition ◽  
Liquid Phase ◽  
Size Distribution ◽  
Iron Ore ◽  
Room Temperature ◽  
Temperature Characteristic ◽  
Iron Ores ◽  
Temperature Characteristics ◽  
Bonding Phase

In this paper, self-characteristics (the room-temperature characteristics and the high-temperature characteristic) of iron ores used in sintering, such as chemical composition, size distribution, assimilation, liquid phase fluidity, self-strength of bonding phase, etc, were studied. Then, the principles of ore-proportioning optimization basing on self-characteristics of iron ore during sintering were proposed. Schemes of ore-proportioning optimization were designed and sinter pot test were carried out．Results of sinter pot confirmed the method of optimizing ore proportioning based on iron ore self-characteristics. This work provides good countermeasure for improving sinter quality and reducing sinter cost as soon as possible, under the condition of making full use of the existing iron ore resources.

scholarly journals Mechanical properties of glass-based geopolymer affected by activator and curing conditions under the optimal aging conditions

2021 ◽  
Author(s):  
Tai-An Chen
Keyword(s):  
High Temperature ◽  
Weight Ratio ◽  
Polymeric Materials ◽  
High Strength ◽  
Curing Temperature ◽  
Test Results ◽  
Curing Conditions ◽  
Positive Effects ◽  
Optimal Value ◽  
Aging Conditions

Inorganic polymeric materials react slowly at room temperature and as a result usually require high-temperature curing. This study used the Arrhenius equation to analyze the correlation between curing temperature and curing duration during high-temperature curing. The test results show that optimal values exist for each alkali equivalent of the activator (weight ratio of Na2O/glass powder), curing temperature, and curing duration. Extending the curing duration and increasing the curing temperature have positive effects when the alkali equivalent is lower than the optimal value. However, over-curing results in invisible cracking in the specimens. Furthermore, despite exhibiting high strength initially, the strength of specimens gradually diminishes after standing in air. To ensure the durability of glass-based geopolymer, the curing temperature should not exceed 70℃, and the curing duration should be less than one day.

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