Remelting of Thermal Spraying Coatings - Technologies, Properties and Applications

2021 ◽  
Vol 1016 ◽  
pp. 1597-1602
Author(s):  
Marek Stanisław Weglowski ◽  
Jerzy Dworak ◽  
Krzysztof Kwiecinski ◽  
Janusz Pikuła ◽  
Krzysztof Krasnowski ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Plasma Spraying ◽  
Thermal Spraying ◽  
Process Research ◽  
Flame Spraying ◽  
Simultaneous Increase ◽  
Arc Spraying ◽  
Heat Sources ◽  
Technological Parameters ◽  
The Right

The most popular spraying technologies include: flame spraying, arc spraying and plasma spraying. Spraying technologies allow for the formation of coatings with a desired chemical composition and thickness. However, such coatings characterize by numerous imperfections associated with the nature of the process itself. It is obvious that some of imperfections in thermal spraying coatings can be eliminated by choosing the right parameters of the process. However, in order to improve the properties and eliminate material discontinuous, it is necessary to conduct the remelting process. Research in most cases, showed that the reduction of porosity and simultaneous increase in hardness are possible only by remelting the coating using different heat sources. By adjusting the technological parameters and remelting speed, it is possible to precisely control the depth of the remelted material and thus the properties of final coatings. The paper presents the remelting processes of thermal spraying coatings in relation to technologies, properties and applications.

The Influence of Spraying Distance on the Chemical Composition of Arc Sprayed Layers

2015 ◽  
Vol 754-755 ◽  
pp. 865-868
Author(s):  
Iuliana Silvia Georgescu ◽  
Silviu Ionuţ Ursache ◽  
Elena Raluca Baciu ◽  
Daniel Hriţcu ◽  
Andrei Victor Sandu ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Chemical Elements ◽  
Thermal Spraying ◽  
Electric Arc ◽  
Filler Material ◽  
Arc Spraying ◽  
Technological Parameters ◽  
Edax Analysis ◽  
Initial Chemical Composition ◽  
Spraying Method

Arc spraying (AS) is a thermal spraying method. The spraying distance represents one of the main technological parameters. EDAX analysis, performed on the sprayed layers (SDA and SDS), have shown differences between the initial chemical composition of the filler material and of the obtained layers. The quantitative variations determined for Ni, Fe and Cr can be explained by: the volatilization process of the chemical elements from the electric arc area; losses increase with increasing the length of the spraying jet.

Ultrasound Examination – Mean of Analysis of the Layers Properties Deposited Through Different Thermal Spraying Methods

2012 ◽  
Vol 186 ◽  
pp. 169-175 ◽  
Author(s):  
Dand Botez Sorin Constantin ◽  
Gabriel Marius Dumitru ◽  
Bogdan Dumitru ◽  
Dina Viorel-Cristian
Keyword(s):  
Comparative Study ◽  
Adhesion Strength ◽  
Ultrasound Examination ◽  
Thermal Spraying ◽  
Atmospheric Plasma Spraying ◽  
Atmospheric Plasma ◽  
Flame Spraying ◽  
Arc Spraying ◽  
Surface Adhesion ◽  
Better Than

Reconditioning materials by thermal spray metalizing is a rapidly growing field. In this paper we conducted a comparative study of three methods of metal deposition: flame spraying, atmospheric plasma spraying, arc spraying. This was done considering two of the properties of layers obtained in metalizing process: surface adhesion strength and porosity. The result of ultrasound examination by immersion shows that adhesion obtained through APS method is better than the others two obtained through AS and FS methods.

Evolution of TSA/TSZ coatings: a review on recent advances on cold gas spraying for steel corrosion protection

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Vicente Albaladejo-Fuentes ◽  
Ana María Martos ◽  
Javier Sánchez ◽  
Irene Garcia-Cano
Keyword(s):  
Corrosion Protection ◽  
Thermal Spraying ◽  
Steel Corrosion ◽  
Cost Effective ◽  
Relevant Information ◽  
Flame Spraying ◽  
Arc Spraying ◽  
Recent Advances ◽  
Cold Gas

Abstract For decades, zinc- and aluminum-based coatings have been considered the best material choice for steel corrosion protection since they may act as a protective barrier and show sacrificial behavior. These coatings are often prepared by galvanizing methods. However, their application by thermal spraying techniques (wire arc spraying, WAS and flame spraying, FS) has been proved as a cost-effective solution for the preparation of long-term corrosion-resistant coatings. This review selectively collects the most relevant information about the application and performance of these two techniques on Zn and Al coatings for corrosion protection. The report summarizes separately the Zn and Al data from the effect of the spraying parameters on coating properties on the one hand, and the results shown in long-term studies carried out in relevant and real exposure conditions, on the other. Finally, this review includes a description and comparison of the most recent advances found out with the novel and emerging spray technique, cold gas spray, for the deposition of Zn and Al coatings for corrosion protection purposes. Nevertheless, the use of this technique has not reached the stage of wide industrial application yet and therefore its long-term performance is unknown, which suggests that there is still room for further development.

scholarly journals SPECIFIC FEATURES OF GAS-FLAME SPRAYING OF ULTRA-HIGH MOLECULAR POLYETHYLENE ON PARA-AMID FABRIC

2020 ◽  
pp. 41-46
Author(s):  
O.G. Devoino ◽  
◽  
A.P. Pilipchuk ◽  
Keyword(s):  
Arbitrary Shape ◽  
Thermal Spraying ◽  
Flame Spraying ◽  
Technological Parameters ◽  
Surface Layers ◽  
Ballistic Resistance ◽  
Gas Flame ◽  
Aramid Fabrics

The analysis of methods for increasing the ballistic resistance of para-aramid fabrics has been carried out. The defining value of friction between the threads of ballistic fabric, which contributes to the deformation of the bullet and its stopping, is noted. The expediency of using gas-flame spraying to create coatings from UHMWPE on the surface of para-aramid fabrics has been substantiated. The choice of material and equipment for gas-thermal spraying has been made. The technological parameters of gas-thermal spraying of UHMWPE on the surface of para-aramid fabrics have been determined. It is shown that the use of gas-flame spraying makes it possible to create surface layers of arbitrary shape.

Technology of obtaining composite conglomerate powders for plasma spraying of high-temperature protective coatings

2021 ◽  
Vol 23 (1) ◽  
pp. 6-20
Author(s):  
Boris Guzanov ◽  
◽  
Natalia Pugacheva ◽  
Evgeniy Slukin ◽  
Tatiana Bykova ◽  
...  
Keyword(s):  
High Temperature ◽  
Chemical Composition ◽  
Spray Drying ◽  
Plasma Spraying ◽  
Gas Turbines ◽  
Nickel Aluminide ◽  
Protective Coatings ◽  
Exothermic Reaction ◽  
Thermal Spraying ◽  
High Heat

Introduction. For parts of gas turbines operating under conditions of corrosion-erosion and intense wear, the most acceptable are compositions containing Ni, Co, Cr, Al, B, Y both in pure form and in the composition of compounds applied on the contact surface during thermal spraying. Modern integrated complexes obtained by combining dissimilar substances in the form of a single composition are promising. Such powders are obtained either by cladding or by conglomeration of finely dispersed starting components into a larger particle. The problem of developing and manufacturing plants for conglomeration of powders is urgent and practically important, since it makes it possible to obtain material for thermal spraying of coatings for high-temperature purposes. The aim of the work is to develop a technological scheme for obtaining powders of the required chemical composition with a given particle shape and size, intended for spraying high-temperature protective coatings. Materials and research methods. A technology is developed for the production of integrated powders for spraying coatings using the method of spray drying and subsequent sintering in vacuum or in an argon-hydrogen atmosphere, which avoids the loss of feedstock due to the return of fine and coarse fractions. A technology for preparing materials for spray drying and granulation is proposed. A gravity type aerodynamic classifier is designed and manufactured, which makes it possible to select automatically the powder fraction necessary for spraying the coating, as well as return the unwanted fraction for recycling. The morphology of the granular powder is determined using a TESCAN scanning electron microscope. The chemical composition of the resulting integrated complexes is determined by X-ray microanalysis on an OXFORD attachment. Results and discussion. The technological conditions for obtaining powders of a given size (40…100 µm) are established. It is shown that the shape of the conglomerate particles after spray drying is close to spherical. On the basis of a multifactor experiment, the optimization of the technological process for obtaining powders Ni-17Cr-10Al-1Y and Ni-22Cr-16Al-1Y with sizes up to 100 µm is performed. It is shown that when conglomerating powders with increased aluminum content (Ni-22Cr-16Al-1Y), it is necessary to take into account the exothermic reaction of nickel aluminide formation and dilute the mixture of initial components before sintering with the finished sintered powder. The resulting integrated complexes are characterized by high heat resistance; therefore they are designed and successfully used for plasma spraying of protective coatings for high-temperature purposes. Conclusions. A technology is developed for obtaining composite conglomerated powders Ni-17C-10Al-1Y and Ni-22Cr-16Al-1Y with particle sizes up to 100 µm and a shape close to spherical. A distinctive feature of this technology is that it avoids the loss of feedstock by returning fine and coarse fractions.

Plasma Spraying of Spray-Dried AI2O3 Powders

2000 ◽  
Author(s):  
G. Bertrand ◽  
B. Hansz ◽  
F. Tourenne ◽  
C. Coddet
Keyword(s):  
Chemical Composition ◽  
Plasma Spraying ◽  
Gas Flow ◽  
Raw Materials ◽  
Thermal Spraying ◽  
Ceramic Coatings ◽  
Crystallographic Structure ◽  
Ceramic Powders ◽  
Spray Process ◽  
Spray Dried

Abstract Today, powder particles diameter used for thermal spraying is generally comprised between 5 and 100µm with a preferred range around 40µm for APS applications. Actually, the future trends in plasma spraying are directed to the use of fine or ultrafine powders and the reduction of the steps between raw materials and coatings. So, the present paper investigates the way to use directly spray dried ceramic powders in suppressing the sintering stage. AI2O3 based powders were obtained by the spray drying process. By optimizing the parameters (slurry composition and injection as well as drying characteristics), a narrow grain size distribution was achieved. Chemical composition and shape of synthesized powders were analyzed by scanning electron microscopy (SEM) equipped with energy dispersive spectrometry (EDS). The crystallographic structure was identified by X-ray diffraction (XRD). Demonstration was made that it is possible to obtain coatings using directly spray dried ceramic powders. The plasma spray process parameters (such as current intensity, gas flow rate, powder feed rate and injection mode, cooling stage,...) have to be managed to achieve cohesive coatings. The structure and chemical composition of these coatings were studied. In this way, the direct use of spray dried powders appears as a promising way to realize ceramic coatings.

scholarly journals Modeling features of the technological process of forestry machines parts strengthening by the method of gas-thermal spraying

2021 ◽  
Vol 2131 (2) ◽  
pp. 022034
Author(s):  
V Kretinin ◽  
A Teppoev ◽  
V Sokolova
Keyword(s):  
Technological Process ◽  
Thermal Spraying ◽  
Flame Spraying ◽  
Technological Parameters ◽  
Wear Resistant ◽  
Wear Resistant Coatings ◽  
Conducting Research ◽  
Gas Flame ◽  
Working Bodies ◽  
Spraying Process

Abstract The efficiency of the working bodies of tillage forestry machines is determined by the sharpness of their soil-cutting elements. The purpose of the study is to substantiate the modes of the technological process of strengthening and recovery of cutting working forestry machines by the method of gas-flame spraying of wear-resistant coatings to increase their wear resistance and preserve the blade sharpness by implementing the self-sharpening effect, which allows increasing their life by 2-3 times. Technical and economic indicators of the gas-flame spraying process, as well as the scope of its application, depend on how well the technological modes of the spraying process are selected. The relevance of the topic is due to the need to increase the durability of tillage tools by strengthening their surfaces treatment. Such effective methods include the technology of recovery and strengthening of the working bodies of tillage machines using the technology of gas-flame spraying. In this regard, the issues of conducting research have become particularly relevant: to identify the relationships of technological parameters during the gas-flame application of wear-resistant coatings; to change the strength characteristics of the material of parts during their recovery, providing the necessary reliability and durability.

Quality analysis and prospects for use of lupin seeds of Belarusian selection

2020 ◽  
Vol 3 (1) ◽  
pp. 22
Author(s):  
Lyudmila Rukshan ◽  
Alena Navazhilova ◽  
Dmitry Kudin
Keyword(s):  
Chemical Composition ◽  
Physical Properties ◽  
Wheat Flour ◽  
Great Influence ◽  
Quality Analysis ◽  
Bakery Products ◽  
Whole Grain ◽  
Technological Parameters ◽  
Protein Food ◽  
Lupin Seeds

The paper investigates technological parameters of the quality of low-alkaloid lupin of five cultivars selected and grown in the Republic of Belarus during the years from 2007 to 2017. Prospects for the use of the obtained seeds have been studied. This study reveals great influence of cultivar and climatic conditions during growth of lupin seeds on correlation of anatomic parts in seeds as well as on their physical properties. Cultivar of lupin seeds Jan is recommended for whole grain flour and graded flour production based on its anatomic composition, uniformity and physical properties. A comparative analysis of chemical composition, quality parameters and technological properties of lupin flour has been done. The chemical composition of lupin flour, of whole grain lupin flour, in particular, has been found to be relatively low in starch, high in protein, food fibers, minerals and organic acids. As a result, whole grain lupin flour has been proved to have higher food value when compared to traditional wheat flour. This paper demonstrates the difference between lupin flour characteristics and those of wheat flour in terms of color, acidity, enzymatic activity and adsorbing properties. This study reveals the possibility of use of lupin flour in bakery products by substituting traditional types of flour with lupin flour at 10-30% levels, as well as by replacing egg products with lupin flour at 25-50% levels. The work highlights the use of lupin flour at the stages of dough kneading, dough preparation, foam and emulsion production mainly by using rapid dough making methods.Practical applicationsRecommendations have been made on the usage of lupin flour in the technological process of bakery products manufacturing, macaroni and flour confectionery products production.

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