scholarly journals Impact of dilution on the microstructure and properties of Ni-based 625 alloy coatings

2014 ◽  
Vol 19 (2) ◽  
pp. 134-144 ◽  
Author(s):  
Tiago Jose Antoszczyszyn ◽  
Rodrigo Metz Gabriel Paes ◽  
Ana Sofia Clímaco Monteiro de Oliveira ◽  
Adriano Scheid
Keyword(s):  
Thermal Conductivity ◽  
Steel Substrate ◽  
Oil Refinery ◽  
Alloy Sample ◽  
Aisi 316L ◽  
Properties Of Coatings ◽  
Low Thermal Conductivity ◽  
Microstructure And Properties ◽  
Nickel Based Alloy ◽  
The Impact

Nickel-based alloy IN 625 is used to protect components of aircrafts, power generation and oil refinery due to an association of toughness and high corrosion resistance. These properties are associated with the chemical composition and microstructure of coatings which depend on the processing parameters and the composition of the component being protected. This paper assessed impact of dilution on the microstructure and properties of the Ni alloy IN 625 deposited by Plasma Transferred Arc (PTA) on two substrates: carbon steel API 5L and stainless steel AISI 316L. Differences due to the interaction with the substrate were maximized analyzing single layer coatings, processed with three deposition current: 120, 150 and 180 A. Correlation with a cast Nickel-based alloy sample contributed to assess the impact of dilution on coatings. Dilution was determined by the area ratio and Vickers hardness measured on the transverse section of coatings. Scanning electron and Laser confocal microscopy and X-ray diffraction analysis were carried out to characterize the microstructure. Results indicated the increasing dilution with the deposition current was deeply influenced by the substrate. Dilution ranging from 5 to 29% was measured on coatings processed on the API 5L steel and from 22 to 51% on the low thermal conductivity AISI 316L steel substrate. Differences on the microstructure and properties of coatings can be associated with the interaction with each substrate. Higher fraction of carbides account for the higher coating hardness when processing on API 5L whereas the low thermal conductivity of AISI 316L and the higher Fe content in solid solution contributed to the lower hardness of coatings.

Microstructure Development During Plasma Spraying of Molybdenum Part 2: Coating Microstructure and Properties

1998 ◽  
Author(s):  
X.Y. Jiang ◽  
S. Sampath ◽  
A. Vardelle ◽  
M. Vardelle ◽  
P. Fauchais
Keyword(s):  
New York ◽  
Deposition Temperature ◽  
Steel Substrate ◽  
Processing Condition ◽  
Physical And Mechanical Properties ◽  
Splat Morphology ◽  
Microstructure Development ◽  
Properties Of Coatings ◽  
Microstructure And Properties ◽  
Coating Microstructure

Abstract This is part II of the two part paper based on international collaboration between the University of Limoges, France and the State University of New York, Stony Brook, USA, aimed at fundamental understanding the relationship between processing condition and microstructure development and properties of thermally sprayed materials. In this study, the effects of deposition temperature on the microstructure and properties development of molybdenum coating was investigated. It is found that with the increase of steel substrate temperature, the molybdenum splat morphology changes from fragmented to more contiguous disk-like shape. The splats on molybdenum substrate show predominantly disk shape. With the increase in deposition temperature, the coating exhibits better lamellar structure with less interlayer pores and debris. The fracture characteristics changes gradually from interlamellar to trans-lamellar and, thermal conductivity is enhanced. Higher deposition temperature improves dramatically the adhesion and bonding of the splats, therefore the physical and mechanical properties of coatings.

scholarly journals Microstructure And Properties Of WC-Co HVAF Coatings Obtained From Standard, Superfine And Modified By Sub-Micrometric Carbide Powders

2015 ◽  
Vol 60 (2) ◽  
pp. 759-766 ◽  
Author(s):  
H. Myalska ◽  
K. Szymański ◽  
G. Moskal
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
High Velocity ◽  
Steel Substrate ◽  
Technological Properties ◽  
Coating Properties ◽  
Properties Of Coatings ◽  
Microstructure And Properties ◽  
Basic Properties

Abstract In this paper, microstructure and some properties of various coatings based on WC-Co obtained by the High Velocity Air Fuel technique are discussed. Initially, two WC-Co 83-17 powders of standard and superfine size were examined as a feedstock for a coatings deposition on a steel substrate. A standard Amperit 526.074 powder and an Inframat superfine powder were applied. Then three different sub-micrometric powders, WC, Cr3C2 and TiC were applied to modify the microstructure of WC-Co (Amperit 526.074). The aim of the investigations was to compare the microstructure and basic properties of coatings deposited from different components. The influence of sub-micrometric additions on mechanical properties of basic coatings was analyzed. Microstructure characterization of powders by using SEM and characterization of their technological properties as well, are presented. For all manufactured coatings obtained by a High Velocity Air Fuel method, the microhardness, porosity, adhesion to a substrate, and fracture toughness were determined. An improvement in WC-Co coating properties, as a result of sub-micrometric carbides addition, was revealed.

The Novel Heating Method for the Sample of Spectral Emissivity Measurement

2011 ◽  
Vol 148-149 ◽  
pp. 951-957 ◽  
Author(s):  
Li Xing ◽  
Zun Dong Yuan ◽  
Min Chen Guo ◽  
Dong Wei ◽  
Li Zhi Cai ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Surface Temperature ◽  
Spectral Emissivity ◽  
The Novel ◽  
Heating Method ◽  
Low Thermal Conductivity ◽  
Measurement Results ◽  
Potential Applications ◽  
Emissivity Measurement ◽  
The Impact

In order to eliminate the temperature difference between center measurement points and surface temperature of the material samples with low thermal conductivity, this paper introduces a new hot airflow double-sided heating method for sample, and describes its principle, application, and the impact of the existing and novel methods on the measurement results of spectral emissivity. Also, we analyze and compare the results of two different samples obtained with these two heating methods. The new method for material samples with low thermal conductivity has outstanding advantages and potential applications.

Study of Microstructure and Properties of Corundum-Calcium Hexaluminate Composite Aggregate

2013 ◽  
Vol 690-693 ◽  
pp. 433-437
Author(s):  
Lv Ping Fu ◽  
Hua Zhi Gu ◽  
Bo Du ◽  
Ao Huang ◽  
Zheng Kun Li
Keyword(s):  
Thermal Conductivity ◽  
Heat Conductivity ◽  
Experimental Results ◽  
Generative Capacity ◽  
Closed Porosity ◽  
Low Thermal Conductivity ◽  
Microstructure And Properties ◽  
Large Numbers ◽  
Calcium Hexaluminate

Effect of adding CaCO3 on the microstructure and properties of corundum was studied, with corundum modified by adding CaCO3 powder, by means of XRD, SEM etc. The experimental results show that when the quantity of CaCO3 powder is not more than 14.1wt%, would obtain corundum-calcium hexaluminate composite aggregate. When a little hexaluminate is generated, it would not increase porosity significantly but closed porosity increase slightly, and the heat conductivity is lower than tabular corundum. Calcium hexaluminate in aggregate grow well and are flakes. There are large numbers of small pores, and distributed uniformly. Composite aggregate has preferable performance of sintered and low thermal conductivity when hexaluminate generative capacity is about 27%.

scholarly journals The impact of lone-pair electrons on the lattice thermal conductivity of the thermoelectric compound CuSbS2

2017 ◽  
Vol 5 (7) ◽  
pp. 3249-3259 ◽  
Author(s):  
Baoli Du ◽  
Ruizhi Zhang ◽  
Kan Chen ◽  
Amit Mahajan ◽  
Mike J. Reece
Keyword(s):  
Crystal Structure ◽  
Thermal Conductivity ◽  
Lattice Thermal Conductivity ◽  
Lone Pair ◽  
Low Thermal Conductivity ◽  
Lone Pair Electrons ◽  
The Impact

The discovery and design of compounds with intrinsically low thermal conductivity, especially compounds with a special bonding nature and stable crystal structure, is a new direction to broaden the scope of potential thermoelectric (TE) materials.

Structure and Thermoelectric Properties of New Quaternary Tin and Lead Bismuth Selenides, K1+xM4-2xBi7+xSe15 (M = Sn, Pb) and K1+xSn5-xBi11+xSe22

2000 ◽  
Vol 626 ◽  
Author(s):  
Antje Mrotzek ◽  
Kyoung-Shin Choi ◽  
Duck-Young Chung ◽  
Melissa A. Lane ◽  
John R. Ireland ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Single Crystal ◽  
Thermoelectric Properties ◽  
Three Dimensional ◽  
Structure Type ◽  
Narrow Gap ◽  
Low Thermal Conductivity ◽  
Seebeck Coefficients ◽  
Metal Atoms ◽  
Anionic Framework

ABSTRACTWe present the structure and thermoelectric properties of the new quaternary selenides K1+xM4–2xBi7+xSe15 (M = Sn, Pb) and K1-xSn5-xBi11+xSe22. The compounds K1+xM4-2xBi7+xSe15 (M= Sn, Pb) crystallize isostructural to A1+xPb4-2xSb7+xSe15 with A = K, Rb, while K1-xSn5-xBi11+xSe22 reveals a new structure type. In both structure types fragments of the Bi2Te3-type and the NaCl-type are connected to a three-dimensional anionic framework with K+ ions filled tunnels. The two structures vary by the size of the NaCl-type rods and are closely related to β-K2Bi8Se13 and K2.5Bi8.5Se14. The thermoelectric properties of K1+xM4-2xBi7+xSe15 (M = Sn, Pb) and K1-xSn5-xBi11+xSe22 were explored on single crystal and ingot samples. These compounds are narrow gap semiconductors and show n-type behavior with moderate Seebeck coefficients. They have very low thermal conductivity due to an extensive disorder of the metal atoms and possible “rattling” K+ ions.

Assessment of the impact of factors of the working environment on the health of workers in oil refining based on the analysis of morbidity

2020 ◽  
pp. 600-600 ◽  
Author(s):  
I. V. Ginko ◽  
T. M. Sushinskaya ◽  
A. L. Rybina
Keyword(s):  
Comparison Group ◽  
Main Group ◽  
Working Environment ◽  
Oil Refinery ◽  
Oil Refining ◽  
Production Environment ◽  
The Impact

Studies have been conducted to assess the impact of factors of the production environment on employees of the oil refinery ofJSC «Naftan». Significant differences with the comparison group on the indicators of SVT were revealed. Priority nosological forms of employees of the main group are identified.

A Novel Poly(Ionic Liquid) as the Thermal Insulating Material

2020 ◽  
Vol 13 (3) ◽  
pp. 241-247
Author(s):  
Wenxin Wei ◽  
Guifeng Ma ◽  
Hongtao Wang ◽  
Jun Li
Keyword(s):  
Thermal Conductivity ◽  
Ionic Liquid ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Flame Resistance ◽  
Insulating Material ◽  
Low Thermal Conductivity ◽  
Thermal Insulating ◽  
Poly Ionic Liquid

Objective: A new poly(ionic liquid)(PIL), poly(p-vinylbenzyltriphenylphosphine hexafluorophosphate) (P[VBTPP][PF6]), was synthesized by quaternization, anion exchange reaction, and free radical polymerization. Then a series of the PIL were synthesized at different conditions. Methods: The specific heat capacity, glass-transition temperature and melting temperature of the synthesized PILs were measured by differential scanning calorimeter. The thermal conductivities of the PILs were measured by the laser flash analysis method. Results: Results showed that, under optimized synthesis conditions, P[VBTPP][PF6] as the thermal insulator had a high glass-transition temperature of 210.1°C, high melting point of 421.6°C, and a low thermal conductivity of 0.0920 W m-1 K-1 at 40.0°C (it was 0.105 W m-1 K-1 even at 180.0°C). The foamed sample exhibited much low thermal conductivity λ=0.0340 W m-1 K-1 at room temperature, which was comparable to a commercial polyurethane thermal insulating material although the latter had a much lower density. Conclusion: In addition, mixing the P[VBTPP][PF6] sample into polypropylene could obviously increase the Oxygen Index, revealing its efficient flame resistance. Therefore, P[VBTPP][PF6] is a potential thermal insulating material.

scholarly journals Characteristics of Cr-B Coatings Produced on Vanadis® 6 Tool Steel Using Laser Processing

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2621
Author(s):  
Aneta Bartkowska
Keyword(s):  
Corrosion Resistance ◽  
Tool Steel ◽  
Laser Processing ◽  
Chemical Elements ◽  
Steel Substrate ◽  
Processing Parameters ◽  
Beam Power ◽  
Laser Beam Power ◽  
High Microhardness ◽  
The Impact

The paper presents the results of a study of the microstructure, chemical composition, microhardness and corrosion resistance of Cr-B coatings produced on Vanadis 6 tool steel. In this study, chromium and boron were added to the steel surface using a laser alloying process. The main purpose of the study was to determine the impact of those chemical elements on surface properties. Chromium and boron as well as their mixtures were prepared in various proportions and then were applied on steel substrate in the form of precoat of 100 µm thickness. Depending on the type of precoat used and laser processing parameters, changes in microstructure and properties were observed. Coatings produced using precoat containing chromium and boron mixture were characterized by high microhardness (900 HV0.05–1300 HV0.005) while maintaining good corrosion resistance. It was also found that too low laser beam power contributed to the formation of cracks and porosity.

Sign in / Sign up

Export Citation Format

Share Document