scholarly journals The effect of heat treatment and impact angle on the erosion behavior of nickel-tungsten carbide cold spray coating using response surface methodology

2021 ◽  
Author(s):  
Marios Kazasidis ◽  
Elisa Verna ◽  
Shuo Yin ◽  
Rocco Lupoi
Keyword(s):  
Heat Treatment ◽  
Response Surface Methodology ◽  
Mass Loss ◽  
Tungsten Carbide ◽  
Response Surface ◽  
Spray Coating ◽  
Impact Angle ◽  
Control Factors ◽  
Heat Treated ◽  
The Impact

AbstractThis study elucidates the performance of cold-sprayed tungsten carbide-nickel coating against solid particle impingement erosion using alumina (corundum) particles. After the coating fabrication, part of the specimens followed two different annealing heat treatment cycles with peak temperatures of 600 °C and 800 °C. The coatings were examined in terms of microstructure in the as-sprayed (AS) and the two heat-treated conditions (HT1, HT2). Subsequently, the erosion tests were carried out using design of experiments with two control factors and two replicate measurements in each case. The effect of the heat treatment on the mass loss of the coatings was investigated at the three levels (AS, HT1, HT2), as well as the impact angle of the erodents (30°, 60°, 90°). Finally, the response surface methodology (RSM) was applied to analyze and optimize the results, building the mathematical models that relate the significant variables and their interactions to the output response (mass loss) for each coating condition. The obtained results demonstrated that erosion minimization was achieved when the coating was heat treated at 600 °C and the angle was 90°.

scholarly journals Heat Treatment of Pine Wood: Possible Effect of Impregnation with Silver Nanosuspension

Forests ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 466 ◽  
Author(s):  
Hamid R. Taghiyari ◽  
Siavash Bayani ◽  
Holger Militz ◽  
Antonios N. Papadopoulos
Keyword(s):  
Heat Treatment ◽  
Mass Loss ◽  
Treated Wood ◽  
High Mass ◽  
Potential Influence ◽  
Pine Wood ◽  
Hot Air ◽  
Heat Treated ◽  
High Mass Loss ◽  
The Impact

The scope of the present work was to study the effects of heat treatment (at different mild temperatures) on the physicomechanical properties of pine wood, and to find out if impregnation with nanosilver may have any potential influence on the impact of heat treatment. Impregnation of wood with a 400-ppm silver nanosuspension was carried out under an initial vacuum pressure of 0.07 MPa, followed by a pressure of 0.25 MPa for thirty minutes, before heat treatment. Heat treatment was carried out under hot air at three relatively mild temperatures, 145, 165, and 185 °C. Results showed improvement of some properties in heat-treated wood at 145 °C. This was indicative of the improving impact caused by hornification and irreversible hydrogen bonding in the course of water movements due to heat treatment; significant fluctuations in the intensities of FTIR spectra bands at 1750–1500 cm−1 were corroborating evidence of chemical alterations in hemicellulose polymer. The high mass loss at temperature 185 °C, and the extreme thermal degradation thereof, overcame the improving effects of hornification and formation of irreversible hydrogen bonds, consequently mechanical properties decreased significantly. Interaction of different elements involved made it hard to predict properties in specimens modified at 165 °C. Impregnation of specimens with nanosilver suspension resulted in significant increase of mass loss in specimens heat-treated at 185 °C, and significant fluctuations in properties of specimens heat-treated at 145 °C.

scholarly journals Effect of Heat Treatment on Smoothie Quality by Response Surface Methodology

Proceedings ◽  
2020 ◽  
Vol 70 (1) ◽  
pp. 6
Author(s):  
Joaquina Pinheiro ◽  
Diana I. Santos ◽  
Elsa M. Gonçalves ◽  
Marta Abreu ◽  
Margarida Moldão-Martins
Keyword(s):  
Heat Treatment ◽  
Response Surface Methodology ◽  
Antioxidant Capacity ◽  
Response Surface ◽  
Fruits And Vegetables ◽  
Total Phenolics ◽  
Treatment Time ◽  
Antioxidant Power ◽  
Quality Properties ◽  
The Impact

Smoothies are a popular and convenient way for to consume bioactive compounds from fruits and vegetables such as total phenolics, carotenoids and flavonoids, with the preservation treatment being an important action to guarantee the safety and extension of shelf-life. The main goal of this study was to evaluate the impact of heat treatment (HT) on smoothie prepared with “Fuji “apple (41%), pineapple (31%), cabbage (8%), pumpkin (10%) and banana (10%), by response surface methodology (RSM), where the temperature (70–100 °C) and treatment time (0.5–10.5 min), were the dependent variables. After optimization of HT conditions, a validation assay was performed to guarantee the minimal changes on color and reduction of 90% of polyphenoloxidase enzyme (PPO). Antioxidant activity (Ferric reducing antioxidant power assay (FRAP), DPPH, ABTS), total phenolics content (TPC), pH and solids soluble content were also analyzed. Predicted models of color parameters (L*, a*, ºh) and PPO enzymatic activity were found to be significant (p < 0.05) with regression coefficients (R2) of 0.84, 0.86, 0.92 and 0.97, respectively. From the RSM-generated model, the HT conditions that ensure a minimal green loss of smoothie and inactivation of PPO enzyme was at 85 °C over 7 min. In the validation study, these conditions were tested and proved to be sufficient to achieve the main goals. In the heat-treated smoothie, increases in TPC (10%) and antioxidant capacity (ABTS: 50%, DPPH: 17%, FRAP: 13%) were attained. This study demonstrated that RSM was efficient to select the optimal conditions of HT and improve the important quality properties that influence the product quality and the potential consumer’s health (TPC and antioxidant capacity).

scholarly journals Optimizing Adsorption of 17α-Ethinylestradiol from Water by Magnetic MXene Using Response Surface Methodology and Adsorption Kinetics, Isotherm, and Thermodynamics Studies

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3150
Author(s):  
Mengwei Xu ◽  
Chao Huang ◽  
Jing Lu ◽  
Zihan Wu ◽  
Xianxin Zhu ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Quadratic Model ◽  
Adsorption Efficiency ◽  
Process Variables ◽  
Adsorption Time ◽  
Initial Concentration ◽  
Independent Variables ◽  
The Impact ◽  
Adsorbent Dose

Magnetic MXene composite Fe3O4@Ti3C2 was successfully prepared and employed as 17α-ethinylestradiol (EE2) adsorbent from water solution. The response surface methodology was employed to investigate the interactive effects of adsorption parameters (adsorption time, pH of the solution, initial concentration, and the adsorbent dose) and optimize these parameters for obtaining maximum adsorption efficiency of EE2. The significance of independent variables and their interactions were tested by the analysis of variance (ANOVA) and t-test statistics. Optimization of the process variables for maximum adsorption of EE2 by Fe3O4@Ti3C2 was performed using the quadratic model. The model predicted maximum adsorption of 97.08% under the optimum conditions of the independent variables (adsorption time 6.7 h, pH of the solution 6.4, initial EE2 concentration 0.98 mg L−1, and the adsorbent dose 88.9 mg L−1) was very close to the experimental value (95.34%). pH showed the highest level of significance with the percent contribution (63.86%) as compared to other factors. The interactive influences of pH and initial concentration on EE2 adsorption efficiency were significant (p < 0.05). The goodness of fit of the model was checked by the coefficient of determination (R2) between the experimental and predicted values of the response variable. The response surface methodology successfully reflects the impact of various factors and optimized the process variables for EE2 adsorption. The kinetic adsorption data for EE2 fitted well with a pseudo-second-order model, while the equilibrium data followed Langmuir isotherms. Thermodynamic analysis indicated that the adsorption was a spontaneous and endothermic process. Therefore, Fe3O4@Ti3C2 composite present the outstanding capacity to be employed in the remediation of EE2 contaminated wastewaters.

Effect of Cooling Rate on Microstructure and Properties of Heat-Treated Fe3Al Intermetallics

2011 ◽  
Vol 189-193 ◽  
pp. 3891-3894
Author(s):  
Ya Min Li ◽  
Hong Jun Liu ◽  
Yuan Hao
Keyword(s):  
Heat Treatment ◽  
Cooling Rate ◽  
Lattice Distortion ◽  
Annealing Furnace ◽  
Microstructure And Properties ◽  
Homogenizing Annealing ◽  
Heat Treated ◽  
Mixed Fracture ◽  
Sand Mould ◽  
The Impact

The casting Fe3Al intermetallics were solidified in sodium silicate sand mould and permanent mould respectively to get different cooling rates. After heat treatment (1000°С/15 h homogenizing annealing + furnace cooling followed by 600°С/1 h tempering + oil quenching), the microstructure and properties of Fe3Al intermetallics were investigated. The results show that the heat-treated Fe3Al intermetallics at higher cooling rate has finer grained microstructure than lower cooling rate, and the lattice distortion increases due to the higher solid solubility of the elements Cr and B at higher cooling rate. The tensile strength and hardness of the Fe3Al intermetallics at higher cooling rate are slightly higher also. However, the impact power of intermetallics at higher cooling rate is 67.5% higher than that at lower cooling rate, and the impact fracture mode is also transformed from intercrystalline fracture at lower cooling rate to intercrystallin+transcrystalline mixed fracture at higher cooling rate.

Application of Tailored Heat Treated Blanks under Quasi Series Conditions

2007 ◽  
Vol 344 ◽  
pp. 383-390 ◽  
Author(s):  
Marion Merklein ◽  
Uwe Vogt
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Local Heat ◽  
Strength Distribution ◽  
Process Window ◽  
Short Term ◽  
Forming Process ◽  
Heat Treated ◽  
Set Up ◽  
The Impact

Tailored Heat Treated Blanks (THTB) are blanks that exhibit locally different strength specifically optimized for the succeeding forming process. The strength distribution is set by a local, short-term heat treatment modifying the mechanical properties of the material. Hence, THTB allow enhancing forming limits significantly leading to shorter and more robust manufacture process chains. In order to qualify the use of THTB under quasi series conditions, the interdependencies of the blank’s local heat treatment and the entire process chain of the car body manufacture have to be analyzed. In this respect, the impact of a short-term heat treatment on the mechanical properties of AA6181PX, a commonly used aluminum alloy in today’s car bodies, was studied. Also the influence of a short-term heat treatment on the coil lubricant, usually already applied by the material supplier, was given a closer look. Based on these experiments process restrictions for the application of THTB in an industrial automotive environment were derived and a process window for the THTB design was set up. In conclusion, strategies were defined how to enhance the found process boundaries leading to a more robust process window.

scholarly journals COLOR CHANGE — MASS LOSS CORRELATION FOR HEAT-TREATED WOOD

2014 ◽  
Vol 2 ◽  
pp. 345-352 ◽  
Author(s):  
Cristina Marinela Olarescu ◽  
Mihaela Campean
Keyword(s):  
Heat Treatment ◽  
Mass Loss ◽  
Color Change ◽  
Treated Wood ◽  
Untreated Wood ◽  
Cost Effective ◽  
Assessment Procedure ◽  
Mathematical Correlation ◽  
Heat Treated ◽  
Two Parameters

Heat treatment is renowned as the most environmentally friendly process of dimensional stabilization that can be applied to wood, in order to make it suitable for outdoor uses. It also darkens wood color and improves wood durability. The intensity of heat treatment can be appreciated by means of two parameters: the color change occured in wood due to the high temperature, and the mass loss, which is a measure of the degree of thermal degradation. In order to find a mathematical correlation between these two parameters, an experimental study was conducted with four European wood species, which were heat-treated at 180°C and 200ºC, for 1-3 hours, under atmosheric pressure.The paper presents the results concerning the color changes and mass losses recorded for the heat-treated wood samples compared to untreated wood.  For all four species, the dependency between the color change and the mass loss was found to be best described by a logarithmic regression equation with R2 of 0.93 to 0.99 for the soft species (spruce, pine and lime), and R2 of 0.77 for beech. The results of this study envisage to simplify the assessment procedure of the heat treatment efficiency, by only measuring the color – a feature that is both convenient and cost-effective. 

T6 Heat Treatment Optimization of Thixoformed LM4 Aluminium Alloy using Response Surface Methodology

2020 ◽  
Vol 3 (1) ◽  
pp. 1-13
Author(s):  
MOHD SHUKOR SALLEH ◽  
Hanizam Hashim ◽  
Mohd Zaidi Omar ◽  
Abu Bakar Sulong ◽  
Soufhwee Abd Rahman ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Response Surface Methodology ◽  
Aluminium Alloy ◽  
Response Surface ◽  
Treatment Optimization ◽  
T6 Heat Treatment ◽  
Heat Treatment Optimization

Variations in Fracture Toughness for Alloy 718 Given a Modified Heat Treatment

1990 ◽  
Vol 112 (1) ◽  
pp. 116-123 ◽  
Author(s):  
W. J. Mills ◽  
L. D. Blackburn
Keyword(s):  
Heat Treatment ◽  
Fracture Toughness ◽  
Fracture Mechanisms ◽  
Alloy 718 ◽  
Percent Confidence Level ◽  
Heat Treated ◽  
Curve Method ◽  
Heat Treated Condition ◽  
The Impact ◽  
Product Forms

Heat-to-heat and product-form variations in the JIC fracture toughness for Alloy 718 were characterized at 24, 427, and 538°C using the multiple-specimen JR-curve method. Six different material heats along with three product forms from one of the heats were tested in the modified heat treated condition. This heat treatment was developed at Idaho National Engineering Laboratory to improve the impact toughness for Alloy 718 weldments, but it has also been found to enhance the fracture resistance for the base metal. Statistical analysis of test results revealed four distinguishable JIC levels with mean toughness levels ranging from 87 to 190 kJ/m2 at 24°C. At 538°C, JIC values were 15 to 20 percent lower than room temperature toughness levels. Minimum expected values of JIC (ranging from 72 kJ/m2 at 24°C to 48 kJ/m2 at 538°C) and dJR/da (27 MPa at 24 to 538°C) were established based on tolerance intervals bracketing 90 percent of the lowest JIC and dJR/da populations at a 95 percent confidence level. Metallographic and fractographic examinations were performed to relate key microstructural features and operative fracture mechanisms to macroscopic properties.

scholarly journals Wood Surface Changes of Heat-Treated Cunninghamia lanceolate Following Natural Weathering

Forests ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 791
Author(s):  
Xinjie Cui ◽  
Junji Matsumura
Keyword(s):  
Heat Treatment ◽  
Wood Surface ◽  
Color Change ◽  
Thermal Modification ◽  
Protective Measure ◽  
Surface Color ◽  
Natural Exposure ◽  
Heat Treated ◽  
The Impact ◽  
Cunninghamia Lanceolate

To quickly clarify the effect of heat treatment on weatherability of Cunninghamia lanceolate (Lamb.) Hook., we investigated the surface degradation under natural exposure. A comparison between heat-treated and untreated samples was taken based on surface color changes and structural decay at each interval. Over four weeks of natural exposure, multiple measurements were carried out. Results show that color change decreased in the order of 220 °C heat-treated > untreated > 190 °C heat-treated. The results also indicate that the wood surface color stability was improved via the proper temperature of thermal modification. Low vacuum scanning electron microscopy (LVSEM) results expressed that thermal modification itself had caused shrinking in the wood surface structure. From the beginning of the weathering process, the heat treatment affected the surface structural stability. After natural exposure, the degree of wood structure decay followed the pattern 220 °C heat-treated > 190 °C heat-treated > untreated. Therefore, when considering the impact on the structure, thermal modification treatment as a protective measure to prevent weathering was not an ideal approach and requires further improvement.

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