The Impact of Heat Treatment on Pyrophyllite Structure and Acid-Soluble Properties

2011 ◽  
Vol 366 ◽  
pp. 326-329 ◽  
Author(s):  
Jun Jun Wu ◽  
Hai Feng Chen ◽  
Shi Jiang Zhao ◽  
Bin Li
Keyword(s):  
Heat Treatment ◽  
Thermal Activation ◽  
Acid Leaching ◽  
Basic Structure ◽  
Hydrochloric Acid Concentration ◽  
Activation Temperature ◽  
Different Temperatures ◽  
Ft Ir ◽  
Heat Activation ◽  
The Impact

This paper studied the influence of heat treatment on the pyrophyllite structure and acid-soluble properties of alumina. Qualitative tests had been performed in studying pyrophyllite crystal at different temperatures by XRD, TG-DTA, FT-IR and quantitative analysis of Al2O3. The quantitative titration method studied the dissolve characteristics of the different heat treatment samples in different acid conditions, and then a numerical simulation was done. The results showed that at temperatures below 480 °C, the pyrophyllite did not change the basic structure. 480~700 °C dehydroxylation reaction occurred, and the structure water of pyrophyllite is removed, and then turned into partial pyrophyllite. Dissolution experiments showed that after thermal activation the behavior of alumina in acid the dissolution was different, which was affected by hydrochloric acid concentration, heat activation temperature and acid leaching time. When the calcinations temperature was 700 °C, the dissolution amount of alumina was largest. These works could provide some theoretical basis for further application of pyrophyllite research.

Optimization of Conditions for Extraction of Acid-Soluble Al2O3 from Pyrophyllite

2011 ◽  
Vol 366 ◽  
pp. 330-333
Author(s):  
Jun Jun Wu ◽  
Hai Feng Chen ◽  
Shi Jiang Zhao ◽  
Bin Li
Keyword(s):  
Hydrochloric Acid ◽  
Acid Concentration ◽  
Thermal Activation ◽  
Acid Leaching ◽  
Hydrochloric Acid Concentration ◽  
Activation Temperature ◽  
Different Temperatures ◽  
Heat Activation ◽  
Silicate Clay ◽  
The Relationship

Pyrophyllite was the cheap, environmentally friendly alumina silicate clay minerals. This paper studied optimization of conditions for extraction of acid-soluble Al2O3 from pyrophyllite. Qualitative tests had been performed in studying pyrophyllite crystal at different temperatures by using scanning electron microscopy. Dissolution experiments showed that after thermal activation the behavior of alumina in acid the dissolution was different, which was affected by hydrochloric acid concentration, heat activation temperature and acid leaching time. When the calcinations temperature was 700 °C and hydrochloric acid concentration was 25%, the dissolution amount of alumina largest. The fit results indicated that the research for the relationship between dissolution and time by Using Exponential function series Asymptotic1 model to fitting match was the best. So the above function could be used to estimate each time the dissolution of alumina from pyrophyllite in hydrochloric acid.

Effect of Heat Treatment on Microstructure Evolution and Mechanical Behavior of SKLB3 Alloy

2017 ◽  
Vol 898 ◽  
pp. 380-386
Author(s):  
Wei Yuan ◽  
Dong Mei Liu ◽  
Qiang Song Wang ◽  
Guo Liang Xie
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Impact Energy ◽  
Hot Forging ◽  
Charpy Impact ◽  
Aging Treatment ◽  
Ni Alloy ◽  
Before And After ◽  
Different Temperatures ◽  
The Impact

In this paper, the effect of heat treatment on the microstructure and mechanical properties of hot forging Cu-Ni alloy was studied. Specimens of hot forged Cu-Ni alloy were subjected to first solution treated at 900oC for 2hrs and then aged at different temperatures for 2hrs. The mechanical properties including tensile performance and impact energy, and the microstructure were measured for specimens before and after heat treatment. The results show that both solution and aging treatment have an influence on the grain growth. After heat treatment, the tensile strength decreases very slightly but the yield strength decreases seriously from 235.96MPa to 136.12MPa, while the elongation increases sharply from 36% to 48%. It was also observed that hardness values of the heat-treated alloys are all lower than that of the hot forged alloy. The measurement of Charpy impact energy with V-type notch was performed at 298K and 77K for different specimens. At both temperatures, the impact energies of the specimens are higher than 200J. The microstructure results show that at both temperatures, the alloys are fractured in a ductile mode.

scholarly journals On the Recovery and Fatigue Life Extension of Stainless Steel 316 Metals by Means of Recovery Heat Treatment

Metals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1290
Author(s):  
Ali Haghshenas ◽  
M. M. Khonsari
Keyword(s):  
Heat Treatment ◽  
Fatigue Life ◽  
Life Extension ◽  
Impact Excitation ◽  
Bending Tests ◽  
Heat Treated ◽  
Different Temperatures ◽  
Three Stages ◽  
Stainless Steel 316 ◽  
The Impact

In this paper, we propose a methodology for enhancing the fatigue life of SS316 by performing intermittent recovery heat-treatment (RHT) in the Argon environment at different temperatures. To this end, fully-reversed fatigue bending tests are conducted on the heat-treated SS316 specimens. Damping values are obtained using the impact excitation technique to assess the damage remaining in the material after each RHT and the corresponding fatigue life. Damping is also used to distinguish the three stages of the fatigue phenomenon and the onset of crack initiation. The results show that by performing intermittent RHTs, the density of dislocation is decreased substantially and fatigue life is improved. Examination of the damping results also reveals that the material becomes more brittle after the RHT due to the decrease in the density of dislocations. The fatigue life of the specimens is governed by these two phenomena.

Effect of Heat Treatment on the Microstructure of TiO2 Nanofibers Prepared by Refluxing in Basic Solution

2008 ◽  
Vol 368-372 ◽  
pp. 800-802 ◽  
Author(s):  
Shi Ying Zhang ◽  
Fan Ping Xiao ◽  
Luo Yi Wu ◽  
Cheng Yong Li ◽  
Zhen Hua Chen
Keyword(s):  
Heat Treatment ◽  
Heat Treatment Temperature ◽  
Treatment Temperature ◽  
Basic Solution ◽  
Tio2 Powder ◽  
Gel Method ◽  
Different Temperatures ◽  
Amorphous Tio2 ◽  
Ft Ir ◽  
Titania Nanofibers

Using tetrabutyltitanate as titanium source, amorphous TiO2 powder was firstly prepared by a sol–miniemulsion–gel method. Prepared powder was refluxed in basic solution and then calcined at different temperatures to synthesize titania nanofibers. The prepared samples were characterized by XRD, TG–DSC, FT–IR and TEM. The results show that when the heat–treatment temperature increases, crystallization of the titania nanofibers occurs with two Ti–OH bonds dehydrate, meanwhile morphology of the fibers is gradually obvious and ratio of length to diameter decreases. When the temperature was raised above 550 °C, titania nanofibers were sintered.

scholarly journals Research of the process of whitening cotton oils by developed adsorbents

2020 ◽  
Vol 1 ◽  
Author(s):  
Ikromov Oybek Abdurasulovich ◽  
Suvanova Fayoza Usmanovna ◽  
Farmonov Zhasur Boykaraevich
Keyword(s):  
Heat Treatment ◽  
Sorption Capacity ◽  
Rice Husk ◽  
Laboratory Tests ◽  
Thermal Activation ◽  
Raw Material ◽  
Different Temperatures

The article presents the results of studying the properties of adsorbents obtained from rice husk. To increase the sorption capacity, the raw material was subjected to heat treatment under various conditions and at different temperatures, and then was used to bleach cotton oils. The amount of added sorbent was from 1 to 4%. According to the results of laboratory tests, adsorbents that have undergone thermal activation at a temperature of 800°С have the highest porosity and bleaching ability. 800°С.

scholarly journals Effect of oak wood heating on cognac spirit matured in new barrel: a pilot study

OENO One ◽  
2003 ◽  
Vol 37 (4) ◽  
pp. 243 ◽  
Author(s):  
Guillaume Snakkers ◽  
Jean-Michel Boulesteix ◽  
Sylvie Estréguil ◽  
Jacqueline Gaschet ◽  
Odile Lablanquie ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Stainless Steel ◽  
Pilot Study ◽  
Steel Cylinder ◽  
Oak Wood ◽  
Different Temperatures ◽  
Wood Heating ◽  
The Impact ◽  
Different Levels

<p style="text-align: justify;">This study investigates the influence of different levels of wood heat treatment on the quality of a Cognac spirit using a pilot barrel model. The pilot barrels were composed of a stainless steel cylinder closed at both ends by a piece of stave. The aim of the study was to analyze the impact of wood heat treatment on Cognac in both analytical and sensory terms and to confirm the validity of the pilot barrel model. The findings give a relatively wide view of the influence on the composition of Cognac of new wood heated at different temperatures. Heating gave notes of «vanilla» and «toasted» to the spirit while excessive heating led to lower quality with the appearance of «fungus» and «dusty». The good quality of the spirits obtained validates the pilot barrel as a model for the extraction of wood compounds by spirit.</p>

Microstructural and Mechanical Behaviour Evaluation of Mg-Al-Zn Alloy Friction Stir Welded Joint

2020 ◽  
Vol 17 (3) ◽  
pp. 8150-8159
Author(s):  
Kulwant Singh ◽  
Gurbhinder Singh ◽  
Harmeet Singh
Keyword(s):  
Heat Treatment ◽  
Friction Stir Welding ◽  
Magnesium Alloys ◽  
Mechanical Performance ◽  
Fuel Efficiency ◽  
Research Work ◽  
Grain Structure ◽  
Tensile Fracture ◽  
Friction Stir ◽  
The Impact

The weight reduction concept is most effective to reduce the emissions of greenhouse gases from vehicles, which also improves fuel efficiency. Amongst lightweight materials, magnesium alloys are attractive to the automotive sector as a structural material. Welding feasibility of magnesium alloys acts as an influential role in its usage for lightweight prospects. Friction stir welding (FSW) is an appropriate technique as compared to other welding techniques to join magnesium alloys. Field of friction stir welding is emerging in the current scenario. The friction stir welding technique has been selected to weld AZ91 magnesium alloys in the current research work. The microstructure and mechanical characteristics of the produced FSW butt joints have been investigated. Further, the influence of post welding heat treatment (at 260 °C for 1 h) on these properties has also been examined. Post welding heat treatment (PWHT) resulted in the improvement of the grain structure of weld zones which affected the mechanical performance of the joints. After heat treatment, the tensile strength and elongation of the joint increased by 12.6 % and 31.9 % respectively. It is proven that after PWHT, the microhardness of the stir zone reduced and a comparatively smoothened microhardness profile of the FSW joint obtained. No considerable variation in the location of the tensile fracture was witnessed after PWHT. The results show that the impact toughness of the weld joints further decreases after post welding heat treatment.

Static and Dynamic Studies of Gasoline in View of its Octane Number and its Toxic Effect

2013 ◽  
Vol 12 (7) ◽  
pp. 451-459
Author(s):  
Ashraf Yehia El-Naggar ◽  
Mohamed A. Ebiad
Keyword(s):  
Toxic Effect ◽  
Aromatic Hydrocarbons ◽  
Octane Number ◽  
Liquid Fuel ◽  
Positive Impact ◽  
Hydrocarbon Composition ◽  
Different Temperatures ◽  
Different Seasons ◽  
The One ◽  
The Impact

Gasoline come primarily from petroleum cuts, it is the preferred liquid fuel in our lives. Two gasoline samples of octane numbers 91 and 95 from Saudi Arabia petrol stations were studied. This study was achieved at three different temperatures 20oC, 30oC and 50oC representing the change in temperatures of the different seasons of the year. Both the evaporated gases of light aromatic hydrocarbons (BTEX) of gasoline samples inside the tank were subjected to analyze qualitatively and quantitatively via capillary gas chromatography. The detailed hydrocarbon composition and the octane number of the studied gasoline samples were determined using detailed hydrocarbon analyzer. The idea of research is indicating the impact of light aromatic compounds in gasoline on the toxic effect of human and environment on the one hand, and on octane number of gasoline on the other hand. Although the value of octane number will be reduced but this will have a positive impact on the environment as a way to produce clean fuel.

Heat Treatment Influence on the Corrosion Resistance of a Cu-Al-Fe-Mn Bronze

2018 ◽  
Vol 69 (5) ◽  
pp. 1055-1059 ◽  
Author(s):  
Mariana Ciurdas ◽  
Ioana Arina Gherghescu ◽  
Sorin Ciuca ◽  
Alina Daniela Necsulescu ◽  
Cosmin Cotrut ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Structural Changes ◽  
Heating Temperature ◽  
Galvanic Corrosion ◽  
Cooling Water ◽  
Open Circuit ◽  
Water Quenching ◽  
Heat Treated ◽  
Different Temperatures

Aluminium bronzes are exhibiting good corrosion resistance in saline environments combined with high mechanical properties. Their corrosion resistance is obviously confered by the alloy chemical composition, but it can also be improved by heat treatment structural changes. In the present paper, five Cu-Al-Fe-Mn bronze samples were subjected to annealing heat treatments with furnace cooling, water quenching and water quenching followed by tempering at three different temperatures: 200, 400 and 550�C. The heating temperature on annealing and quenching was 900�C. The structure of the heat treated samples was studied by optical and scanning electron microscopy. Subsequently, the five samples were submitted to corrosion tests. The best resistance to galvanic corrosion was showed by the quenched sample, but it can be said that all samples are characterized by close values of open-circuit potentials and corrosion potentials. Concerning the susceptibility to other types of corrosion (selective leaching, pitting, crevice corrosion), the best corrosion resistant structure consists of a solid solution, g2 and k compounds, corresponding to the quenched and 550�C tempered sample.

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