Effect of Thermal Aging on the Transformation Temperatures and Specific Heat Characteristics of 9Cr-1Mo Ferritic Steel

2008 ◽  
Vol 279 ◽  
pp. 85-90 ◽  
Author(s):  
B. Jeya Ganesh ◽  
S. Raju ◽  
E. Mohandas ◽  
M. Vijayalakshmi
Keyword(s):  
Heat Capacity ◽  
Phase Transformation ◽  
Specific Heat ◽  
Room Temperature ◽  
Martensitic Steel ◽  
Thermal Ageing ◽  
Phase Transformation Temperature ◽  
Scanning Calorimetry ◽  
Temperature Range ◽  
Martensite Microstructure

The effect of thermal ageing on the heat capacity and transformation behaviour of behaviour of 9Cr-1Mo-0.1C (wt.%) ferritic / martensitic steel has been studied using differential scanning calorimetry (DSC) in the temperature range 473 to 1273 K. It is found that a-ferrite + carbide ® g-austenite phase transformation temperature is only mildly sensitive to microstructural details; but the enthalpy change associated with this phase transformation and especially, the change in specific heat around the transformation regime are found to be dependent on the starting microstructure generated by thermal ageing treatment. Prolonged ageing for about 500 to 5000 hours in the temperature range 823 to 923 K contributed to a decrease in heat capacity, as compared to the normalised and tempered sample. The martensite microstructure is found to possess the lowest room temperature CP among different microstructures.

Study of the heat capacity of VZhM4 nickel superalloy using differential scanning calorimetry, adiabatic and mixing calorimetry

2021 ◽  
Vol 87 (12) ◽  
pp. 30-35
Author(s):  
S. Yu. Shorstov ◽  
P. S. Marakhovsky ◽  
S. I. Pakhomkin ◽  
M. G. Razmakhov
Keyword(s):  
Differential Scanning Calorimetry ◽  
Heat Capacity ◽  
Specific Heat ◽  
Nickel Superalloy ◽  
Measurement Procedure ◽  
Aviation Industry ◽  
New Materials ◽  
Scanning Calorimetry ◽  
Temperature Range ◽  
High Level

An increase in the operating temperatures of assemblies and parts of modern aircraft is a key task for the aviation industry which entails developing of new materials that meet the increased requirements for their operational characteristics. A high level of the accuracy and reliability of the determined properties is one of the most important factors in designing high-temperature metal, ceramic and heat-shielding materials. The features of a particular measurement procedure, as well as their hardware design, do not always ensure the specified accuracy of experiments over the entire temperature range. We present the results of studying the heat capacity of VZhM4 nickel superalloy in the temperature range 100 – 1360° C by the methods of differential scanning calorimetry (DSC), adiabatic and mixing calorimetry. The data of the DSC analysis of the alloy, the temperatures of phase transformations and temperature dependences of the specific heat of the material are analyzed along with the assessment of their accuracy at different temperature intervals. A comparative analysis of the studied measurement procedures complements the research. The results obtained can be used in the development of new materials and in the study of the specific heat capacity of metal products in a wide temperature range.

Development of the room temperature protocol based on room temperature ionic liquids and surfactant ionic liquids for the synthesis of derivatives of 2-amino-thiazoles and thermo-physical analysis of the synthesized derivatives using TGA-DSC.

2020 ◽  
Vol 10 ◽  
Author(s):  
Chandrakant Sarode ◽  
Sachin Yeole ◽  
Ganesh Chaudhari ◽  
Govinda Waghulde ◽  
Gaurav Gupta
Keyword(s):  
Thermal Analysis ◽  
Heat Capacity ◽  
Ionic Liquids ◽  
Specific Heat ◽  
Specific Heat Capacity ◽  
Room Temperature ◽  
Heat Capacity Data ◽  
General Strategy ◽  
Capacity Data ◽  
Derivatives Of

Aims: To develop an efficient protocol, which involves an elegant exploration of the catalytic potential of both the room temperature and surfactant ionic liquids towards the synthesis of biologically important derivatives of 2-aminothiazole. Objective: Specific heat capacity data as a function of temperature for the synthesized 2- aminothiazole derivatives has been advanced by exploring their thermal profiles. Method: The thermal gravimetry analysis and differential scanning calorimetry techniques are used systematically. Results: The present strategy could prove to be a useful general strategy for researchers working in the field of surfactants and surfactant based ionic liquids towards their exploration in organic synthesis. In addition to that, effect of electronic parameters on the melting temperature of the corresponding 2-aminothiazole has been demonstrated with the help of thermal analysis. Specific heat capacity data as a function of temperature for the synthesized 2-aminothiazole derivatives has also been reported. Conclusion: Melting behavior of the synthesized 2-aminothiazole derivatives is to be described on the basis of electronic effects with the help of thermal analysis. Additionally, the specific heat capacity data can be helpful to the chemists, those are engaged in chemical modelling as well as docking studies. Furthermore, the data also helps to determine valuable thermodynamic parameters such as entropy and enthalpy.

Specific heats of polymer powders by differential scanning calorimetry

1982 ◽  
Vol 60 (14) ◽  
pp. 1853-1856 ◽  
Author(s):  
Eva I. Vargha-Butler ◽  
A. Wilhelm Neumann ◽  
Hassan A. Hamza
Keyword(s):  
Differential Scanning Calorimetry ◽  
Specific Heat ◽  
Scanning Calorimetry ◽  
Temperature Range ◽  
Specific Heats ◽  
Powdered Form ◽  
Polymer Powders

The specific heats of five polymers were determined by differential scanning calorimetry (DSC) in the temperature range of 300 to 360 K. The measurements were performed with polymers in the form of films, powders, and granules to clarify whether or not DSC specific heat values are dependent on the diminution of the sample. It was found that the specific heats for the bulk and powdered form of the polymer samples are indistinguishable within the error limits, justifying the determination of specific heats of powders by means of DSC.

INDIRECT MEASUREMENT OF Zn-DOPED In2S3 NANOFILMS' SPECIFIC HEAT CAPACITY

2008 ◽  
Vol 07 (04n05) ◽  
pp. 229-233 ◽  
Author(s):  
S. LAZZEZ ◽  
K. BOUBAKER BEN MAHMOUD ◽  
M. AMLOUK
Keyword(s):  
Heat Capacity ◽  
Electron Microscope ◽  
Specific Heat ◽  
Specific Heat Capacity ◽  
Room Temperature ◽  
Thermal Analyses ◽  
Indirect Measurement ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
The Mean

ZnIn 2 S 4 nanofilms were grown on In 2 S 3 substrates. The band gap of ZnIn 2 S 4 barriers was approximately 2.8 eV at room temperature. The morphology and structure of the obtained nanofilms were already investigated via transmission electron microscope (TEM), scanning electron microscope (SEM) and X-ray diffraction analyses.1,2 In this paper, thermal analyses are performed via a photothermal technique, which has been used to indirectly evaluate the specific heat capacity of the obtained Zn -doped nanofilms. The yielded value for an optimal zinc-to-indium ratio, x (0.33), at the mean room temperature (T∞ = 301 K ), was Cs ≈ 411.5 J K -1 kg -1.

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