scholarly journals Wetting Kinetics and Microstructure Analysis of BNi2 Filler Metal over Selective Laser Melted Ti-6Al-4V Substrate

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4666
Author(s):  
Jiankun Liu ◽  
Guanpeng Liu ◽  
Hua Ouyang ◽  
Yulong Li ◽  
Ming Yan ◽  
...  
Keyword(s):  
Filler Metal ◽  
Optical Microscope ◽  
Promoting Effect ◽  
Tc4 Titanium Alloy ◽  
Initial Stage ◽  
Different Temperatures ◽  
Three Stages ◽  
Wetting Kinetics ◽  
Kinetics Of

The wetting kinetics of nickel-based filler metal (BNi2) over selective laser-melted Ti-6Al-4V (SLMed TC4) titanium alloy in a protective argon atmosphere is experimentally investigated using a real-time in situ hot stage equipped with an optical microscope. The spreading processes at different temperatures are similar, and the overall wetting/spreading process can be roughly divided into three stages: (i) an initial stage, (ii) a rapid spreading stage, and (iii) an asymptotic stage. Moreover, the wetting kinetics of the BNi2/SLMed TC4 system can be expressed by empirical power exponential function Rn~t with n = ~1. In the process of spreading, Ti-based solid solution (Ti(ss)) and intermetallic compound (Ti2Ni and TiB2) were formed at the interface within the reaction domain, and the phase transition of α’ martensitic to α-Ti and β-Ti also took place. The influence of elevated temperature on the spreading and wetting kinetics of the BNi2/SLMed TC4 system was studied, and the results show that the increase of temperature has a slightly promoting effect on the spreading, but a limited impact on the value of n. In addition, the spreading and wetting kinetics of BNi2/SLMed TC4 system are similar to those of BNi2 on conventional forged TC4 substrate.

In Situ FT-IR Studies on the Amine-Catalyzed Urethane Reaction Kinetics of 1,3-Butanediol

2012 ◽  
Vol 472-475 ◽  
pp. 2223-2226
Author(s):  
Peng Fei Yang
Keyword(s):  
Rate Constant ◽  
Phenyl Isocyanate ◽  
Hydroxyl Group ◽  
Activation Entropy ◽  
Ir Studies ◽  
Initial Stage ◽  
Different Temperatures ◽  
Ft Ir ◽  
Kinetics Of

Phenyl isocyanate is used to react with 1,3-butanediol at different temperatures. Toluene is used as solvent and 1,4-diazabicyclo[2,2,2]octane is used as catalyst. In-situ FT-IR is used to monitor the reaction to work out rate constant, Arrhenius equation and Eyring equation. The urethane reaction has been found to be a second order reaction, and the rate constant seems different between initial stage and final stage. The activation energy (Ea), activation enthalpy (ΔH) and activation entropy (ΔS) for the urethane reaction of primary hydroxyl group are calculated out, which are 26.4 kJ•mol-1, 23.6 kJ•mol-1and -186.6 J•mol-1•k-1, respectively. They are very useful to reveal the reaction mechanism.

In Situ FT-IR Studies on the Catalytic Reaction Kinetics of 1,2-Propanediol with Phenyl Isocyanate

2012 ◽  
Vol 450-451 ◽  
pp. 131-134
Author(s):  
Peng Fei Yang
Keyword(s):  
Rate Constant ◽  
Arrhenius Equation ◽  
Phenyl Isocyanate ◽  
Activation Entropy ◽  
Ir Studies ◽  
Initial Stage ◽  
Different Temperatures ◽  
Ft Ir ◽  
Kinetics Of

Phenyl isocyanate is used to react with 1,2-propanediol in different temperatures. Toluene is used as solvent and triethylamine is used as catalyst. In-situ FT-IR is used to monitor the reaction to work out rate constant, Arrhenius equation and Eyring equation. The urethane reaction has been found to be a second order reaction, and the rate constant seems different between initial stage and final stage. The activation energy (Ea), activation enthalpy (ΔH) and activation entropy (ΔS) for the urethane reaction are calculated out, which are 74.1 kJ•mol-1, 71.3 kJ•mol-1 and -30.5 J•mol-1•k-1, respectively. They are very useful to reveal the reaction mechanism.

In Situ FT-IR Studies on the Urethane Reaction Kinetics of 3-Methyl-1,3-Butanediol in Nitrogen-Contained Solvent

2012 ◽  
Vol 446-449 ◽  
pp. 1743-1746
Author(s):  
Peng Fei Yang
Keyword(s):  
Rate Constant ◽  
Phenyl Isocyanate ◽  
Hydroxyl Group ◽  
Activation Entropy ◽  
Ir Studies ◽  
Initial Stage ◽  
Different Temperatures ◽  
Ft Ir ◽  
Kinetics Of

Phenyl isocyanate is used to react with 3-methyl-1,3-butanediol at different temperatures. Dimethylformamide is used as solvent. In-situ FT-IR is used to monitor the reaction to work out rate constant, Arrhenius equation and Eyring equation. The urethane reaction has been found to be a second order reaction, and the rate constant seems different between initial stage and final stage. The activation energy (Ea), activation enthalpy (ΔH) and activation entropy (ΔS) for the urethane reaction of tertiary hydroxyl group are calculated out, which are 75.2 kJ•mol-1, 72.4 kJ•mol-1and -44.8 J•mol-1•k-1, respectively. They are very useful to reveal the reaction mechanism.

In Situ FT-IR Studies on the Urethane Reaction Kinetics of 1,3-Butanediol in Nitrogen-Contained Solvent

2012 ◽  
Vol 472-475 ◽  
pp. 1911-1914
Author(s):  
Peng Fei Yang
Keyword(s):  
Rate Constant ◽  
Phenyl Isocyanate ◽  
Hydroxyl Group ◽  
Activation Entropy ◽  
Ir Studies ◽  
Initial Stage ◽  
Different Temperatures ◽  
Ft Ir ◽  
Kinetics Of

Phenyl isocyanate is used to react with 1,3-butanediol at different temperatures. Dimethylformamide is used as solvent. In-situ FT-IR is used to monitor the reaction to work out rate constant, Arrhenius equation and Eyring equation. The urethane reaction has been found to be a second order reaction, and the rate constant seems different between initial stage and final stage. The activation energy (Ea), activation enthalpy (ΔH) and activation entropy (ΔS) for the urethane reaction of primary hydroxyl group are calculated out, which are 90.9 kJ•mol-1, 88.2 kJ•mol-1and 20.2 J•mol-1•k-1, respectively. They are very useful to reveal the reaction mechanism.

GROWTH OF OXIDE LAYER ON GERMANIUM (011) SUBSTRATE UNDER DRY AND WET ATMOSPHERES

1999 ◽  
Vol 06 (06) ◽  
pp. 1053-1060 ◽  
Author(s):  
N. TABET ◽  
J. AL-SADAH ◽  
M. SALIM
Keyword(s):  
Simple Model ◽  
Oxide Film ◽  
Growth Kinetics ◽  
Photoelectron Spectroscopy ◽  
Early Stage ◽  
X Ray ◽  
Apparent Thickness ◽  
Different Temperatures ◽  
Kinetics Of

X-ray Photoelectron Spectroscopy (XPS) has been used to investigate the oxidation of (011) Ge substrates. The sample surfaces were CP4-etched, then annealed in situ, at different temperatures, for various durations. Dry and wet atmospheres were used. The oxidation rate during the early stage was increased by the presence of moisture in the atmosphere. A simple model was used to define and determine an apparent thickness of the oxide film from XPS measurements. The time dependence of the apparent thickness is consistent with a partial coverage of the surface by oxide islands. The growth kinetics of the oxide islands obeys a nearly cubic law.

Effects of Solvent Polarity on the Urethane Reaction of 1,2-Propanediol

2012 ◽  
Vol 450-451 ◽  
pp. 38-41
Author(s):  
Peng Fei Yang
Keyword(s):  
Rate Constant ◽  
Solvent Polarity ◽  
Reaction Rates ◽  
Phenyl Isocyanate ◽  
Second Order Reaction ◽  
Polar Solvents ◽  
Initial Stage ◽  
Ft Ir ◽  
Kinetics Of

The urethane reaction kinetics of 1,2-propanediol with phenyl isocyanate are investigated in different solvents, such as xylene, toluene and dimethylformamide. In-situ FT-IR is used to monitor the reaction to work out rate constant. It showsthat the urethane reaction has been found to be a second order reaction, solvents largely affects reaction rates. The reaction is largely accelerated in polar solvents, following the order of dimethylformamide > toluene > xylene. Further more, when dimethylformamide is used as solvent, the rate constants are different between initial stage and final stage, which belongs to different hydroxyls in 1,2-propanediol. However, when toluene or xylene is used as solvent, the rate constant is the same. That is, there is no reactivity difference for hydroxyls in 1,2-propanediol.

Nitridation Isothermal Kinetics of In Situ β-Sialon Bonded Al2O3-C Refractories

2016 ◽  
Vol 697 ◽  
pp. 572-575
Author(s):  
Xue Qing Yang ◽  
Nai Peng ◽  
Cheng Ji Deng
Keyword(s):  
Activation Energy ◽  
Apparent Activation Energy ◽  
Isothermal Kinetics ◽  
Nitridation Reaction ◽  
Result Show ◽  
Different Temperatures ◽  
Two Stages ◽  
Kinetics Of ◽  
And Diffusion

The kinetics of in-situ β- Sialon bonded Al2O3-C (SAC) refractories were investigated by TGA techniques via isothermal nitridation experiments at different temperatures. The result show that the nitridation process of in-situ β-Sialon bonded Al2O3-C refractories can be divided into two stages: the nitridation reaction rate controlling stage in the first 10 min, and the apparent activation energy of nitridation reaction is 370 kJ/mol ; then the reaction is controlled by both chemical reaction and diffusion rate in the following 110 min, the apparent activation energy of nitridation reaction is 410 kJ/mol.

scholarly journals Study of Recrystallization Kinetics of 1565ch Aluminum Alloy during hot deformation

2020 ◽  
Vol 326 ◽  
pp. 05001
Author(s):  
Vasiliy Yashin ◽  
Alexander Drits ◽  
Evgenii Aryshenskii ◽  
Ilya Latushkin ◽  
Ekaterina Chitnaeva
Keyword(s):  
Growth Rate ◽  
Aluminum Alloy ◽  
Optical Microscope ◽  
Recrystallization Process ◽  
System Alloy ◽  
Industrial Practice ◽  
Cast Ingot ◽  
Recrystallization Kinetics ◽  
Different Temperatures ◽  
Kinetics Of

The present study addresses recrystallization process in Al-Mg-Mn-Zn-Zr system alloy samples. The samples are collected from cast ingot, produced by casting to industrial DC mold, and homogenized based on standard industrial practice. After that the samples were rolled with different hot rolling schedules. Rolled samples were annealed at different temperatures and their resultant microstructure was examined using optical microscope. During the study new grains nuclei generation rate and their growth rate were determined, analytical records, describing recrystallization kinetics, were obtained, main differences, specific to this alloy recrystallization in 350 ºС-450 ºС temperature range, were identified.

Characterization of WELD Heat Affected Zone of ASTM A709 HPS 100W

2012 ◽  
Vol 706-709 ◽  
pp. 1474-1480
Author(s):  
Avidipto Biswas ◽  
Philip Nash ◽  
Sreeharsha Lalam ◽  
Steve Jansto
Keyword(s):  
Impact Toughness ◽  
Heat Affected Zone ◽  
Optical Microscope ◽  
Structure Property ◽  
Different Temperatures ◽  
Gleeble 3500 ◽  
Relationship Of ◽  
Weld Heat

The weld heat affected zone (HAZ) of HPS 100W was characterized in terms of microstructure and mechanical properties. HAZ simulation was carried out in a GLEEBLE 3500 along with in-situ dilation tests at different peak temperatures of 850°C, 1100°C, 1300°C and 1350°C with heat input of 2kJ/mm. Subsequently, impact toughness data were obtained at different temperatures by means of Charpy tests. The microstructures were characterized using optical microscope, SEM and TEM to correlate the structure-property relationship of the HAZ. Under the tested conditions, all the simulated HAZs exhibited higher impact toughness than the base metal.

The Amount Effect of Catalyst on the Urethane Reaction of 1,2-Propanediol in Xylene

2012 ◽  
Vol 450-451 ◽  
pp. 197-200 ◽  
Author(s):  
Peng Fei Yang
Keyword(s):  
Rate Constants ◽  
Catalyst Concentration ◽  
Phenyl Isocyanate ◽  
Order Reaction ◽  
Second Order Reaction ◽  
Amount Effect ◽  
Initial Stage ◽  
Ft Ir ◽  
Kinetics Of

The urethane reaction kinetics of 1,2-propanediol with phenyl isocyanate is monitored with in-situ FT-IR with xylene as solvent. Triethylamine is used as catalyst and its amount effect is investigated. Rate constants for the reaction with different concentrations of triethylamine are worked out. The urethane reaction has been found to be a second order reaction and the reaction is largely accelerated with the increase of catalyst concentration. Furthermore, when triethylamine is used as catalyst, the rate constants are different between initial stage and final stage, which belong to different hydroxyls in 1,2-propanediol. However, the rate constant is the same when there is no catalyst, which shows no reactivity difference for hydroxyls in 1,2-propanediol.

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