Influence of PBO Fibers Heat-Treatment on Physical-Chemical Properties and Surface

2012 ◽  
Vol 512-515 ◽  
pp. 2076-2079
Author(s):  
Zhao Lei ◽  
Yuan Jun Song ◽  
Jing Jing Wu ◽  
Dai Shi ◽  
Li Ying Zhu ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Tensile Strength ◽  
Chemical Properties ◽  
Nitrogen Atmosphere ◽  
Sem Analysis ◽  
Single Fiber ◽  
Physical Chemical ◽  
Different Temperatures

The influence of heat-treatment in nitrogen atmosphere at different temperatures, time and stress on the physical–chemical properties and the surface of PBO fibers were investigated through Single fiber tensile, TG and SEM analysis. The results show that the tensile strength of PBO fibers dose not change so much before 600°C, but for heat-treatment at 650°C, there is a significant decrease in strength. Heat-treatment also makes the surface of fibers rougher than untreated fibers.

Effects of Different Heat Treatment Temperatures on the Properties of Quartz Fibers

2010 ◽  
Vol 105-106 ◽  
pp. 115-118 ◽  
Author(s):  
Qi Hong Wei ◽  
Chong Hai Wang ◽  
Zhi Qiang Cheng ◽  
Ling Li ◽  
Hong Sheng Wang ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Tensile Strength ◽  
Phase Transformation ◽  
Fiber Strength ◽  
Single Fiber ◽  
Significant Phase ◽  
Surface Micromorphology ◽  
Heat Treated ◽  
Different Temperatures ◽  
Crystallization Heat

In this paper, XRD was engaged in studying phase transformation of quartz fibers, SEM was engaged in studying the surface micromorphology of quartz fibers heat treated at different temperatures, and the tensile strength was measured by a single fiber strength electronics instrument. The results indicate that surface infiltration agent have been iliminated after heat treatment at 500°C, and the tensile strength decreaced significantly. The higher the temperature was, the more the tensile strength decreaced. There were no significant phase transformation and no crystallization heat treatmented at 500~800°C. But there were some round and strip bulges, and scap defects on the surface. With temperature increasing,some scab defects and bulges began to flake off, and some new rifts and cracks were formed. This was one of the important factors that decreaced tensile strength markedly.

scholarly journals Effects of Different Solid Solution Temperatures on Microstructure and Mechanical Properties of the AA7075 Alloy After T6 Heat Treatment

2019 ◽  
Vol 38 (2019) ◽  
pp. 892-896 ◽  
Author(s):  
Süleyman Tekeli ◽  
Ijlal Simsek ◽  
Dogan Simsek ◽  
Dursun Ozyurek
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Solid Solution ◽  
Tensile Strength ◽  
Tensile Tests ◽  
Solution Temperature ◽  
T6 Heat Treatment ◽  
Microstructure And Mechanical Properties ◽  
Different Temperatures

AbstractIn this study, the effect of solid solution temperature on microstructure and mechanical properties of the AA7075 alloy after T6 heat treatment was investigated. Following solid solution at five different temperatures for 2 hours, the AA7075 alloy was quenched and then artificially aged at 120∘C for 24 hours. Hardness measurements, microstructure examinations (SEM+EDS, XRD) and tensile tests were carried out for the alloys. The results showed that the increased solid solution temperature led to formation of precipitates in the microstructures and thus caused higher hardness and tensile strength.

Preparation of Glass-Ceramics Using Molybdenum Tailings

2011 ◽  
Vol 284-286 ◽  
pp. 1431-1434 ◽  
Author(s):  
Jin Rui Zhang ◽  
Ru Wang
Keyword(s):  
Heat Treatment ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Crystalline Phase ◽  
Glass Ceramics ◽  
Chemical Properties ◽  
The Other ◽  
Raw Material ◽  
Physical Chemical ◽  
Nucleation Agents

In order to utilization the molybdenum tailings which be deposited in large quantities. Test used it to prepare glass-ceramics as main raw material, TiO2 as nucleation agents and CaO-Al2O3-SiO2 system and wollastonite as the principal crystalline phase. Heat treatment system of glass-ceramics was based on the differential thermal analysis. The crystalline phase, microstructure and characteristics of glass-ceramics were analysis by XRD, SEM and physical, chemical properties test. The result shows that the performance of glass-ceramics was superior to the other types of building decoration stone.

scholarly journals Influence of Temperature and Heat Treatment Regime on Chemical Properties of Pork Meat

2012 ◽  
Vol 6 (3-4) ◽  
Author(s):  
Dragan Vujadinović ◽  
Željka Marjanović-Balaban
Keyword(s):  
Heat Treatment ◽  
Chemical Properties ◽  
Effect Of Temperature ◽  
Processed Meat ◽  
Pork Meat ◽  
Scientific Publications ◽  
Treatment Processes ◽  
Heat Treatment Regime ◽  
Different Temperatures ◽  
Dry Heat Treatment

The real importance of meat in human nutrition has been defined during the last century. Professional and scientific publications of the twentieth century are often written about the nutritional value of meat. Thermal processing of meat is as old as civilization itself. Meat drying as a procedure for a longer shelf life, probably first appeared as a result of some accident in which the fresh meat has been exposed to heat. The first works about the problems of heat treatment of pork were published in the 1950s.The aim of this paper was to investigate the effect of temperature and different methods of heat treatment on chemical properties of processed pork meat. To determine the optimal conditions for various heat treatment processes, in this paper, meat processing was performed at different temperatures, and set the temperature range from 51 ºC to 100 ºC. Therefore, the meat is processed by dry heat treatment (roasting) and cooking in water (at atmospheric pressure). Then, the change of chemical composition of processed meat was noted (moisture content, ash, fat, protein, micronutrients).

Temperature, osmotic and acidic activity of infusion solutions as an integral part of their mechanism of action

2021 ◽  
Vol 19 (2) ◽  
pp. 175-182
Author(s):  
Natalia A. Urakova
Keyword(s):  
Blood Plasma ◽  
Chemical Properties ◽  
Aerobic Metabolism ◽  
Chemical Action ◽  
Routes Of Administration ◽  
Biological Objects ◽  
Physical Chemical ◽  
Different Temperatures ◽  
Cold Infusion ◽  
And Function

A review of the literature shows that the physical-chemical properties of infusion solutions can be an integral part of the mechanism of their local action on the routes of administration. This new scientific and practical direction in clinical pharmacology was born at the end of the 20th century in Russia. Initially, it was found that isotonic solutions of glucose, mannitol, and sodium chloride with different temperatures have different local effects on the metabolism and viability of isolated biological objects such as mitochondria and blood plasma. At the same time, it was shown that increasing the temperature of solutions from +37 to +45C accelerates the metabolism of these biological objects, increases their reactivity and enhances their response to the action of many drugs-activators of metabolism and function. And vice versa, lowering the temperature of these solutions from +37 to +20C and below (up to 0C) slows down their metabolism, reduces their reactivity, weakens their response to the action of drugs-activators of metabolism and function, and also increases survival in conditions of ischemia and hypoxia. These results allowed us to recommend warm infusion solutions as universal means of activating aerobic metabolism in tissues and the response of tissues to drugs with local physical-chemical action, and cold infusion solutions as universal means of inhibiting aerobic metabolism in tissues and increasing the resistance of tissues to the action of drugs on them. Following this, it was shown that many infusion solutions do not have isoosmotic activity, since the osmotic activity of drugs is not controlled. Therefore, one part of the solutions has hypotonic activity, and the other part has hypertonic activity. Therefore, sometimes the infusion solution can increase the hypoosmotic or hyperosmotic activity of the blood plasma. Then it was shown that the absolute majority of infusion solutions do not have a pH of 7.4. At the same time, very many infusion solutions have acidic activity, so they have an acidifying effect on the blood. The chronology of the development of inventions based on the achievements of the physical-chemical pharmacology of infusion agents is shown.

scholarly journals Grain Refinement and Improved Mechanical Properties of EUROFER97 by Thermo-Mechanical Treatments

2021 ◽  
Vol 11 (22) ◽  
pp. 10598
Author(s):  
Giulia Stornelli ◽  
Andrea Di Schino ◽  
Silvia Mancini ◽  
Roberto Montanari ◽  
Claudio Testani ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Tensile Strength ◽  
Heat Treatments ◽  
Treatment Temperature ◽  
Steel Plates ◽  
Experimental Campaign ◽  
Different Temperatures ◽  
Fusion Applications ◽  
Cold Rolled

EUROFER97 steel plates for nuclear fusion applications are usually manufactured by hot rolling and subsequent heat treatments: (1) austenitization at 980 °C for 30 min, (2) rapid cooling and (3) tempering at 760 °C for 90 min. An extended experimental campaign was carried out with the scope of improving the strength of the steel without a loss of ductility. Forty groups of samples were prepared by combining cold rolling with five cold reduction ratios (20, 40, 50, 60 and 80%) and heat treatments at eight different temperatures in the range 400–750 °C (steps of 50 °C). This work reports preliminary results regarding the microstructure and mechanical properties of all the cold-rolled samples and the effects of heat treatments on the samples deformed with the greater CR ratio (80%). The strength of deformed samples decreased as heat treatment temperature increased and the change was more pronounced in the samples cold-rolled with greater CR ratios. After heat treatments at temperature up to 600 °C yield stress (YS) and ultimate tensile strength (UTS) of samples deformed with CR ratio of 80% were significantly larger than those of standard EUROFER97 but ductility was lower. On the contrary, the treatment at 650 °C produced a fully recrystallized structure with sub-micrometric grains which guarantees higher strength and comparable ductility. The work demonstrated that EUROFER97 steel can be strengthened without compromising its ductility; the most effective process parameters will be identified by completing the analyses on all the prepared samples.

Effects of heat treatment of cream on the physical–chemical properties of model oil-in-buttermilk emulsions

2012 ◽  
Vol 26 (1) ◽  
pp. 88-93 ◽  
Author(s):  
D. Guggisberg ◽  
M. Chollet ◽  
K. Schreier ◽  
R. Portmann ◽  
L. Egger
Keyword(s):  
Heat Treatment ◽  
Chemical Properties ◽  
Physical Chemical ◽  
Model Oil

Effect of Heat Treatment on Mechanical and Tribological Properties of Centrifugally Cast Functionally Graded Cu/Al2O3 Composite

2017 ◽  
Vol 140 (2) ◽  
Author(s):  
Manu Sam ◽  
N. Radhika
Keyword(s):  
Heat Treatment ◽  
Wear Resistance ◽  
Centrifugal Casting ◽  
Casting Process ◽  
Sem Analysis ◽  
Functionally Graded ◽  
Dry Sliding Wear ◽  
Centrifugally Cast ◽  
Mechanical And Tribological Properties ◽  
Different Temperatures

A functionally graded Cu–10Sn–5Ni metal matrix composite (MMC) reinforced with 10 wt % of Al2O3 particles was fabricated using the centrifugal casting process with dimension Φout100 × Φin85 × 100 mm. The mechanical and wear resistance of the composite has been enhanced through heat treatment. Samples from of the inner zone (9–15 mm) were considered for heat treatment, as this zone has higher concentration of less dense hard reinforcement particles. The samples were solutionized (620 °C/60 min) and water quenched followed by aging at different temperatures (400, 450, and 550 °C) and time (1–3 h). Optimum parametric combination (450 °C, 3 h) with maximum hardness (269 HV) was considered for further analysis. Dry sliding wear experiments were conducted based on Taguchi's L27 array using parameters such as applied loads (10, 20, and 30 N), sliding distances (500, 1000, and 1500 m), and sliding velocities (1, 2, and 3 m/s). Results revealed that the wear rate increased with load and distance whereas it decreased initially and then increased with velocity. Optimum condition for maximum wear resistance was determined using signal-to-noise (S/N) ratio. Analysis of variance (ANOVA) predicted the major influential parameter as load, followed by velocity and distance. Scanning electron microscope (SEM) analysis of worn surfaces predicted the wear mechanism, observing more delamination due to increase in contact patch when applied load increased. Results infer 8% increase in hardness after heat treatment, making it suitable for load bearing applications.

scholarly journals Physical-Chemical Properties of Thermoactivated Defecate for Purification of Acid Waste Waters

2019 ◽  
Vol 9 (2) ◽  
pp. 1184-1186
Keyword(s):  
Heat Treatment ◽  
Physicochemical Properties ◽  
Functional Groups ◽  
Chemical Properties ◽  
Adsorption Properties ◽  
Waste Waters ◽  
Thermally Activated ◽  
Physical Chemical ◽  
Acidic Wastewater ◽  
Acid Waste

In this work, we studied the physicochemical properties of thermally activated defecate at 650°C and studied their neutralizing and adsorption properties in the treatment of acidic wastewater. It was found that after heat treatment at 650°C the main functional groups of the defect, i.e. CaCO3 practical has not changed

scholarly journals INFLUENCE OF COMMERCIAL THERMAL TREATMENT ON Eucalyptus grandis Hill ex Maiden WOOD PROPERTIES

2021 ◽  
Vol 45 ◽  
Author(s):  
Carolina Aparecida Barros Oliveira ◽  
Karina Aparecida de Oliveira ◽  
Julio Cesar Molina ◽  
Vinicius Borges de Moura Aquino ◽  
André Luis Christoforo
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Thermal Treatment ◽  
Eucalyptus Grandis ◽  
Treated Wood ◽  
Wood Properties ◽  
Treatment Temperature ◽  
Saturated Steam ◽  
Physical Chemical ◽  
Different Temperatures

ABSTRACT This study aimed to evaluate the influence of commercial thermal treatment on Eucalyptus grandis considering its physical, chemical, and mechanical properties. The wood samples were heat-treated in an autoclave with saturated steam and pressure application at four different temperatures: 155, 165, 175, and 185 ºC. The physical, chemical, and mechanical properties were altered due to the heat treatment. The extractives content varied between 6.06% and 28.75%; lignin between 28.93% and 37.96%; holocellulose between 65.01% and 38.12%. The mechanical properties reduced significantly with the increase of the heat treatment temperature. Through the set of data obtained, it was possible to generate significant and high precision regression models capable of estimating such properties for heat treatment temperatures not studied experimentally, enabling the determination of the most suitable temperature of heat treatment to achieve a certain property value of the treated wood.

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