Influence Of Heating Temperature Research Articles

Influence of heating temperature and time on mechanical-degradation, microstructures and corrosion performances of Teflon/granite coated aluminum alloys used for non-stick cookware

This study explores the functional characteristics (erosion, corrosion, mechanical damage, and microstructural features) of non-stick cookware made from aluminum alloys. Typically coated with polytetrafluoroethylene (PTFE-Teflon) or ceramic for non-stick properties, we conducted a systematic investigation using corrosion, abrasion, and mechanical tests on six types of cookware from different manufacturers (Manuf-1-6). The cookware was heated at various temperatures [Room temperature (RT), 100, 175, 250, & 350 °C] and times (45 & 120 min). Tests included Taber wear, Adhesive Pull-off, hot & RT corrosion, and surface roughness measurements. Characterization involved optical microscopy, scanning electron microscope (SEM) with electron backscattered diffraction (EBSD), and x-ray diffraction (XRD). Ceramic-coated cookware from Manuf-4 demonstrated superior mechanical strength, wear, and corrosion resistance due to refined microstructures. Manuf-1's PTFE-coated cookware also performed well. Optimal results were observed when heating below 250 °C for up to 45 min. Prolonged heating and temperatures beyond 250 °C adversely affected internal structures of all cookware. Thus, it is advisable to use Al-based non-stick cookware below 250 °C for a maximum of 45 min.

Influence of heating temperatures and storage on the odor of duck meat and identification of characteristic odorous smell compounds

To clarify the characteristic odor of compounds present in duck meat, especially reheating after storage, the effect of duck breast cooked at three temperatures (90 °C, 100 °C, 105 °C) and reheating after 7 days of storage was studied. Electronic nose analysis and sensory evaluation revealed a significant increase (p < 0.05) in reheated duck meat odor after 7 days of storage. The 90 °C treatment group had the heaviest odor, which increased by 12.19 % after seven days of storage. Using headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS), 60 volatile flavor compounds were identified across various groups. Although the volatile compounds were consistent among different groups, their relative contents varied. By combining the sensory evaluation results with the Relative Odor Activity Value (ROAV) of these flavor compounds, chemometric orthogonal partial least squares discriminant analysis (OPLS-DA) was used to identify the following 9 characteristic volatile compounds: 2-methylbutanal, pentanal, octanal, heptanal, hexanal, (E)-2-octenal, (E)-2-nonenal, and 2-pentyl furan

Nanosized La0.4Gd0.2Sr0.4MnO3 manganites: From magnetic refrigeration to hyperthermia method

The structural, magnetic, and magnetocaloric characteristics of the nanosized La0.4Gd0.2Sr0.4MnO3 manganites were discussed based on the influence of heating temperature (700 and 1000 °C). We investigated it, further, to present the strong link between magnetic refrigeration and hyperthermia technique. Both samples are nanosized according to the study of the scanning electron microscopy and the X-ray diffraction patterns (Scherrer and Williamson-Hall plots). Analyzing the thermal evolution of the magnetizations proves that various magnetic states are present in both samples, superparamagnetism, spin-glass, ferromagnetism, and paramagnetism. We demonstrated that the Curie temperature is between 318 and 331 K, which is the ideal range for the hyperthermia approach. The relative cooling power at 6 T is around 404.085 J/Kg for LGSM_1000; thus, this sample is an excellent candidate for magnetic cooling. It is a great achievement result that the rate of evolution from LGSM_700 to LGSM_1000 is 3213.26 %.

Mechanical properties and acoustic emission characteristics of deep hard coal after segmented high-temperature treatment

Based on engineering background that local heating of coal seam is uneven due to underground coal gasification, coal-bed gas exploitation via heat injection, spontaneous combustion of coal seam, etc., segmented heating coal sample was used to simulate coal seam under uneven heating condition, and experimental study on mechanical behaviors of coal sample after segmented heat treatment at high temperatures was conducted. Test results show that temperature at 100 °C ~ 400 °C did not reach ignition temperature of deep hard coal for the experiment and was not enough to change main ingredients of coal sample, which less affected compression strength, elastic modulus, acoustic emission behavior of coal sample. Although compaction stage-elastic stage-plastic stage-broken stage appeared in compression stress–strain curve of coal sample, height increase led to decrease of compression strength, elastic modulus of coal sample, cumulative amplitude and ringing count for acoustic emission in the form of power function. Meanwhile, it is found that final failure modes of coal sample after segmented heat were mainly shear failure and separation failure and friction mixed failure was secondary. In addition, influence of heating temperature at 100 °C ~ 400 °C on failure modes of coal sample was small. However, height increase in the heating section of coal sample made shear failure surface gradually move to the heating section and separation failure surface moved with the change of contact surface position between heating section and non-heating section. Furthermore, the integral failure degree of coal sample was more serious. Finally, based on variation behaviors of acoustic emission parameter for coal sample after segmented heating, inversion formula on acoustic emission parameter for strength of coal sample was discussed and verified via experimental result of coal sample with different segmented heat height after heating treatment at 200 °C.

Cordierite-based ceramics from stevensite clay and coal fly ash

ABSTRACT Cordierite-based ceramic is one of the most interesting engineering materials that has attractive and multidisciplinary assets, such as low thermal expansion coefficient, excellent thermal shock resistance, high refractoriness, good mechanical properties, and so on. In this work, cordierite-based ceramics were prepared mainly from stevensite-rich clay or coal fly ash (CFA) and stevensite-rich clay using a solid-state interaction process. The influence of heating temperature, in the range of 800–1250°C, and starting materials on the microstructure-temperature evolutions and mechanical strength were evaluated using TGA-DTA, XRD, FTIR, SEM, and dilatometric analysis. The results revealed, for both formulations heating in the temperature range 800–1100°C, the transformation of stevensite-rich clay into enstatite and its polymorphisms. Further heating induced the formation of the cordierite phase at 1200°C, for the formulation consisted mainly of stevensite-rich clay and CFA, and at 1250°C for that contained mainly stevensite-rich clay. The addition of CFA to stevensite-rich clay enhanced its reactivity and involved the increase in mechanical strength from 5 MPa to 15 MPa at 1200°C.

Influence of heating temperature on the optical response properties and surface relief patterns of TiO2/GeO2/ormosils composite films containing azobenzene

With the progress of modern integrated optical technology, organic-inorganic composite materials have been widely used in integrated optoelectronic devices. Because of satisfying optical response properties among azobenzene, it will be an ideal choice to introduce the material into organic-inorganic composite materials. TiO2/GeO2/ormosils composite films containing azobenzene were prepared by combining the solgel technique with the spin-coating process. The optical transmission modes and loss of as-prepared samples at different transmission wavelengths were researched by a prism coupler. The result shows that the composite film is multi-mode transmission at the transmission wavelength of 633 nm and single-mode transmission at 1538 nm. The transmission loss is sufficient for applications in optical elements. The response properties and Fourier transform infrared spectroscopy of as-prepared samples at different heating temperatures were also studied. The composite films obtained at 50°C have the best optical response properties. Furthermore, the banding energy and chemical composition among the films were measured through x-ray photoelectron spectroscopy. Finally, the surface topography of as-prepared samples was observed by atomic force microscopy. The surface of the composite film appears with patterns of relief under the appropriate temperature. The above results show that the as-prepared TiO2/GeO2/ormosils composite films containing azobenzene will be a kind of ideal material in the field of integrated optics applications.

Temperature effect on mechanical performance of recycled glulam towards to sustainable production

In order to utilize recycled glulam as basic elements in novel composite structural components towards to sustainable production, the physical and mechanical properties of recycled glulam after exposed to elevated temperatures were experimentally studied, by considering the effect of heating duration (2, 4 and 6 h) and heating temperature (60, 100, 120, 160 and 200 °C). The failure modes and strength of the recycled glulam under compression and shear were analyzed respectively in detail. The results show that the influence of heating temperature on the color change of the specimens is greater than that of heating duration, among which 160 °C is the critical temperature for the obvious color change of glulam. According to the test results, the prediction formulas of weight loss ratio and dimensional change ratio under the influence of heating duration and temperature are established. The compressive strength parallel to the grain of glulam first increases and then decreases, and the shear strength decreases with the increase of heating duration and temperature. The prediction model of mechanical properties of recycled glulam under the influence of heating duration and temperature is established. The decreasing speed of the descending section in the compressive stress-strain curve of glulam increases with the increase of heating duration and temperature. The descending section of the shear stress-strain curve shows two-stage sharp drops due to the obvious brittleness during shear failure. The compression constitutive model and shear constitutive model affected by heating duration and temperature are proposed.

Effect of heating treatment on the microstructural evolution and dynamic tensile properties of Ti-6Al-4V alloy produced by selective laser melting

In this paper, the influence of heating treatment on the microstructure and dynamic tensile properties of Ti-6Al-4 V alloy processed by selective laser melting (SLM) was systematically studied considering the influence of heating temperature. The microstructure of SLMed Ti-6Al-4 V consisted of nearly full acicular α’ martensite, and it decomposed into α + β phase after heating treatments, basket-wave and Widmanstatten morphologies were obtained with different heating temperature. Little change of texture intensity was detected in the as-built sample compared with heat-treated counterparts, moreover, dense LAGBs formed in the heat-treated samples, which will have great influence on the strength and ductility. As the heating temperature increased, the strength including ultimate tensile strength (UTS) and yield strength (YS) gradually decreased, the strain to fracture (εf) increased at first, then tended to drop once temperature exceeded the β transus (Tβ). Good balance of strength and ductility can be achieved with α + β treatment, sample treated at 925 °C had excellent UTS of 1114 MPa and εf of 15.4%, namely decreased by 17% and increased by 31% comparing with the as-built counterpart. Lots of interface phase was observed within the heat-treated samples, and in which dense deformation twins were observed after high strain rate tensile testing, thus led to good ductility by the twinning-induced plasticity mechanism.

Selective Extraction of Ni from Superalloy Scraps by Molten Mg-Zn

Bearing significant concentrations of high value and critical metals, superalloy scraps require comprehensive recycling for metal reclamation. In this study, nickel-based superalloy was treated with molten Mg-Zn for the selective extraction of nickel. The influence of heating temperature, the molar ratio of Mg to Zn in the molten metal, Mg-Zn/superalloy mass ratio, and heating time on metal extraction were investigated. Using the heating temperature of 800 °C, the Mg/Zn molar ratio of 9/1, the Mg-Zn/superalloy mass ratio of 5/1, and heating time of 240 min, the extraction rate of 97.1% was achieved for Ni, and the extraction rates of Fe, Cr and refractory metals (Nb, Mo and Ti) were all less than 1%. In the subsequent vacuum distillation process, nickel with a purity of 98.3 wt% was obtained. Therefore, the proposed method is a short, clean, and efficient process for selectively extracting nickel from the superalloy scraps.

Influence of heating temperature and holding time on the formation sequence of iron aluminides at the interface of Fe/Al coatings

Fe/Al coatings designed with different compositions were fabricated by cold spray. The effects of heat treatment on the formation of iron aluminides, such as FeAl, Fe3Al and Fe2Al5, at the Fe/Al interface were investigated. The formation sequence of iron aluminides was strongly influenced by heating temperature and the holding time. Enthalpy calculation method was used to explain the formation sequence of iron aluminides, as a supplement to Fe/Al binary phase diagram. By combining these two methods, the process of diffusion and interfacial reactions can be clarified. As a result, the heat treatment schedule can be optimized to regulate the formation sequence of iron aluminides formed at the interface, which will help inhibit the brittleness and improve the mechanical properties of Fe/Al coatings.

Eco-friendly extraction of Mastocarpus stellatus carrageenan for the synthesis of gold nanoparticles with improved biological activity

Carrageenan was extracted from Mastocarpus stellatus using hot water extraction under atmospheric and pressurized conditions. The influence of heating temperature during a non-isothermal heating profile up to temperatures in the range 70–190 °C was studied to evaluate the extraction yields and properties of the carrageenan fraction. Under the selected conditions (130 °C), extracted carrageenan (CMs) was used for the green synthesis of gold nanoparticles (AuNPs). After the optimization of the reaction conditions, the synthesized gold nanoparticles (Au@CMs) were characterized by UV–Vis spectroscopy, Z potential measurements, electron microscopy, and X-ray diffraction analysis, which confirmed the formation of spherical, polycrystalline, and negatively charged nanoparticles with a mean diameter of 14.3 ± 2.1 nm. The study conducted by scanning transmission electron microscopy, energy dispersive X-ray analysis and mapping confirmed the presence of carrageenan stabilizing AuNPs. Finally, Fourier transformed infrared spectroscopy was performed to analyze the functional groups of CMs involved in the reduction and stabilization of AuNPs. The selective cytotoxicity and the antioxidant activity of the Au@CMs were evaluated in different cell lines and compared to the CMs. Au@CMs showed an improved antioxidant capacity in cells under oxidative stress and the induction of apoptosis in a monocytic cell line, while no antitumor effect was observed in a lung endothelial cell line.

Prussian blue analogue derived carbon-based composites toward lightweight microwave absorption

Carbon-based composites derived from metal organic frameworks (MOFs) have attracted much interest for microwave absorption. However, most studies only focus on the influence of heating temperature rather than the composition of derivatives on microwave absorption ability. In this work, four kinds of derivatives are obtained from Prussian blue analogue (PBA) after heating treatment. It is found that the annealing atmosphere has a significant influence on material compositions, thus the electromagnetic (EM) parameters and carbon graphitization degree are tuned. As a result, the CoFe/Carbon (CoFe/C) composite was derived from CoFe-PBA precursor with Ar atmosphere, which reached minimum reflection loss (RLmin) value of −44.6 dB and effective absorption bandwidth (fe, the RL value less than −10 dB) of 5.5 GHz at 2.15 mm. For the NiFe/Carbon (NiFe/C) composite, the RLmin of −41 dB and fe of 4.8 GHz can be obtained at the thickness of 1.65 mm. The optimal fe of 6.0 GHz is obtained when the matching thickness was 2.0 mm. Given the lightweight, ultrathin, strong microwave attenuation capability, as well as broad effective absorption bandwidth, these carbon-based composites derived from PBA precursors are promising for practical applications.

Effect of heating temperature and cooling rate on the microstructure and mechanical properties of a Mo-rich two phase α + β titanium alloy

In this work, influence of heating temperature and cooling rate on microstructure and mechanical properties of a Ti–6Al–1V–4Mo–Si alloy was investigated. The samples were heated to β (1020 °C) and α + β (950 °C and 850 °C) phase field followed by furnace cooling, air cooling and oil quenching. Basketweave morphology was witnessed for samples furnace cooled from β phase field, while Widmanstatten microstructure was observed for most air-cooled samples. For samples oil quenched from β phase field, HCP martensite (αʹ) was formed, while for samples heated in α + β phase field, lamellar α with α′ was observed. Oil quenching from the β phase field resulted in high strength and low elongation. The strength decreased and elongation increased with reduction in the heating temperature. Highest elongation (~ 16%) was obtained for samples heated to 850 °C followed by furnace cooling. The elastic modulus displayed a wide range of values (70–150 GPa) depending on the processing conditions.

Research on the influence of heat treatment temperature on bearing capacity of high steel grade pipeline during in-service welding

During the welding of in-service pipeline, natural gas is continuously transported in the pipeline, which maintains a high gas pressure. Therefore, the welding process is completed under strong cooling conditions, and welding delay crack is easy to occur. Preheating before welding and heat treatment after welding can effectively control the hardened microstructure, reduce the residual stress and ensure the welding quality. In this study, the influence of heating temperature on the bearing capacity of high steel grade pipe during in-service welding repair was studied. The high temperature tensile test was used to simulate the bearing capacity of the pipe under heating and high temperature environment. It is found that when the heating temperature is below 400°C, the pipe strength remains at the original level. With the increase of heating temperature, when the test temperature is higher than 400°C, the yield strength and tensile strength of the pipe decrease significantly. When the test temperature is 450°C, the yield strength and tensile strength of the material decrease by 15.8% and 11.1%, respectively, compared with the normal temperature, which are lower than the pipe standard requirements. Therefore, it is suggested that when the heat treatment temperature is higher than 400°C during in-service welding repair, it is necessary to consider reducing the pipeline pressure. At the same time, the box furnace heat treatment method was adopted to heat treat the pipe, and the tensile properties of the pipe after heat treatment were tested to analyze the bearing capacity of the pipe after heat treatment. It is found that when the heating temperature is higher than 700°C, the tensile properties of high grade pipeline steel pipe decrease sharply. It is suggested that when the heat treatment temperature is higher than 700°C, the risk assessment of the service safety of the heat treated pipeline should be carried out.

Performance analysis of free piston Stirling engine based on the phasor notation method

The free piston Stirling engine (FPSE) is a couple system of dynamics and thermodynamics. Due to the complicated and interactive relationships between the dynamic parameters and thermodynamic parameters, the performance of the FPSE is always difficult to predict and evaluate. The phasor notation method is proposed based on a thermodynamic-dynamic coupled model of a beta-type FPSE in this paper. The output power and efficiency under the different heating temperature and charging pressure are analysed and compared. In addition, based on the Sage numerical model, the influences of heating temperature and charging pressure on the pistons’ displacement amplitudes, power work and efficiency are revealed. This study can provide the assistance for the performance analysis, prediction and optimization of the FPSE.

Influence of heating temperatures on the component distribution of distillates derived from walnut shell bio-oil

Influence of heating temperatures on the component distribution of distillates distilled from walnut shell bio-oils was studied. Meanwhile, distillates were further separated into water-soluble and water-insoluble fraction to characterize product distribution. The results showed that distillate fraction yield increased with strengthening heating temperature from 120to 300°C.Aromatic hydrocarbons (e.g. naphthalene) and carboxylic acids (e.g. acetic acid) significantly concentrated in water-insoluble fraction as heating temperatures were below 240°C. Notably, the relative concentration of aromatic and carboxylic compounds in the water-insoluble fraction derived from 300°C was 13.86 and 3.15 times higher than that of crude bio-oil, respectively. Large amounts of phenols such as phenol and guaiacol was distilled as heating temperatures exceeded 240°C, which induced enhanced yield of water-insoluble fraction. Moreover, the moisture of all the water-soluble fractions was higher than 60 wt.%, which demonstrated the water-soluble fraction remarkably concentrated moisture. In addition, undetected components (e.g. butyl 2-ethylacetate and cyclopentanone) in crude bio-oil surprisingly existed in distillates and the total moisture of distillates was higher than that of crude bio-oils, which proved esterification and polycondensation reactions occurred in bio-oil distillation process. Furthermore, the component distribution of distillates also indicated modifying heating temperatures effectively enriched commodity chemicals. Note that water-insoluble fraction distilled from 300°C exhibited relative concentration of phenol, guaiacol, 4-methyl-2-methoxyphenol, 4-ethyl-2-methoxyphenol and 4-propyl-2-methoxyphenol was 109%, 160%, 84%, 53% and 444% higher than that in crude bio-oil, respectively.

Dynamics affected memory for crystallization behaviors of poly (d-lactic acid)

Dynamics of polymer chains not only is a fundamental bridge between the structures and properties of polymers but also plays a crucial role in the formation of polymer structures. The slow crystallization caused low crystallinity of Poly (lactic acid) (PLA) is the bottleneck for its applications. The chain dynamics affected memory for recrystallization morphology and behavior of poly (d-lactic acid) (PDLA) were observed by POM and characterized by DSC. The POM images showed that the PDLA could outline the morphology of original banded spherulites after recrystallization from melting of the original spherulites. The re-formed crystal inherited the crystalline location from the original crystalline morphology, forming a circle ring morphology that is following up the initial banded spherulites, even though the circle ring was constructed of smaller spherulites. DSC results showed various crystallization behaviors of PLA recrystallization with different thermal history. The influence of heating temperature, keeping time, and cooling rate on the recrystallization morphology were investigated and discussed. It was proposed that the adjustment and change of PDLA chain conformation is more difficult in various states between the crystalline and melt than that of other polymers, which relates to the strength of melt and entropy.

Analysis of the non-isothermal resin impregnation process of carbon fibre reinforced composite wing spar structure

This paper presents non-isothermal resin impregnation process of high-performance light weight composite wing spar structure for trainer aircrafts. The manufacturing process of the spar is simulated in PAM-RTM software. In this research developed a reliable model of resin impregnation process simulation to determine the exact infusion time and optimize the resin inlet ports for large scale aircraft structure without using the expensive trial and error experimental approches. The work reported the use of different heating temperature processes to manufacture wing spar from carbon fibre-reinforced epoxy resin matrix composite laminates by using VARI. The influence of heating temperature during the infusion stage on the resin viscosity and impregnation time was analyzed. These results indicate that a proper heating temperature during the infusion process is necessary for quality control and manufacturing time reduction. The error between theoretical simulation and experimental studies is no more than 10%.

Influence of heating temperatures on structure and microstructure of chamotte–carbon composites

The reaction between chamotte and active carbon at high temperature and low oxygen partial pressure conditions has been investigated. Both components react at temperatures above 1400°C where cristobalite is reduced by the carbon while increases the mullite content. At 1600°C mullite tends to disappear due to the reduction reaction leading to the formation of alumina. The reaction between chamotte and active carbon in these conditions produces the reduction of silica and mullite. This process increases with the reaction time although not all the active carbon is consumed. The graphite nanodomain size of the active carbon tends to decrease with respect to the original size with both the temperature and the reaction time. The microstructures of the obtained materials present a glassy phase due to the inherent presence of impurities in chamotte, and where small particles, pores and mullite needles are also observed. The presence of this glassy phase becomes more pronounced with the treating temperature while solid particles and pores tend to disappear, moreover, the formation of the glassy phase occurs in a less extent due to the higher concentration of active carbon. The presence of the liquid glassy phase also favours the formation of the long-needle like mullite crystals.

Совместная деформируемость и влияние температуры нагрева при диффузионной сварке на формирование структуры многослойных Nb-Al композитов

Совместная деформируемость и влияние температуры нагрева при диффузионной сварке на формирование структуры многослойных Nb-Al композитов