scholarly journals Structure and Tribological Properties of Ni–Cr–Al-Based Gradient Coating Prepared by Detonation Spraying

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 218
Author(s):  
Bauyrzhan Rakhadilov ◽  
Meruyert Maulet ◽  
Madi Abilev ◽  
Zhuldyz Sagdoldina ◽  
Rauan Kozhanova
Keyword(s):  
Aluminum Content ◽  
High Hardness ◽  
Technological Parameters ◽  
Coating Structure ◽  
Detonation Spraying ◽  
Filling Degree ◽  
Substrate Level ◽  
Sprayed Coatings ◽  
Spraying Method ◽  
Formation Phase

In this paper, Ni–Cr–Al coatings were deposited using the detonation spraying method. The aim was to investigate how technological parameters influence coating structure formation, phase composition and tribological performances. We observed that the degree to which the barrel is filled with an O2/C2H2 gas mixture strongly influences the chemical composition of manufactured coatings. High degrees of barrel filling led to a decrease in aluminum content in the coating. Filling degrees of 40% and 50% produced sprayed coatings in which only Ni–Cr phases could be found. When the filling degree was reduced up to 25%, Ni–Al phases began to form in the sprayed coatings. Gradient Ni–Cr–Al coatings were produced by gradually reducing the filling degree from 50% to 25%. These coatings are characterized by Ni–Cr near the substrate level with Ni–Cr and Ni–Al phases at higher levels. The results obtained confirm that gradient Ni–Cr–Al coatings exhibit high hardness as well as good wear resistance.

Wear Characteristics of the Sprayed Coatings With Amorphous Material

2005 ◽  
Author(s):  
Myoung-Seoup Han ◽  
Sang-Ek Lee ◽  
Dae-Young Kim ◽  
Joong-Geun Youn
Keyword(s):  
Amorphous Materials ◽  
Amorphous Material ◽  
High Hardness ◽  
Wear Property ◽  
Hvof Spraying ◽  
Arc Spray ◽  
Hvof Spray ◽  
Sprayed Coating ◽  
Sprayed Coatings ◽  
Spraying Method

Characteristics of the sprayed amorphous material’s coating have been investigated in order to improve the life of liners used in a blasting system. The amorphous materials of interest were commercial Fe-Cr-B alloys and the processes employed were arc spray and HVOF spray. Erosion wear property of the coatings were evaluated using a steel grit blasting machine and actual blasting system. The coating produced by HVOF spraying method showed a very dense structure so that porosity content of the coating was less than 1% and split was not formed. Due to these features with its high hardness, the wear resistance of the HVOF sprayed coating was superior to that of the arc sprayed coating. Microstructural characteristic of the amorphous material’s coating were analyzed using SEM, EDX and XRD.

scholarly journals Obtaining multilayer coatings by the detonation spraying method

2021 ◽  
Vol 5 (2) ◽  
pp. 148-154
Author(s):  
D.N. Kakimzhanov ◽  
B.K. Rakhadilov ◽  
D.B. Buitkenov ◽  
L.G. Zhurerova ◽  
M.K. Rakhadilov ◽  
...  
Keyword(s):  
Phase Composition ◽  
Multilayer Coating ◽  
Gas Mixture ◽  
Multilayer Coatings ◽  
Al2o3 Coating ◽  
Technological Parameters ◽  
Detonation Spraying ◽  
Al2o3 Phase ◽  
Degree Of Filling ◽  
Spraying Method

This work were studied the effect of technological parameters of detonation spraying on the phase composition and tribological characteristics on the bases of NiCr and Al2O3 coatings. As well as there was obtained and investigated multilayer coating on the bases of NiCr/NiCr- Al2O3/Al2O3 . It was determined that during detonation spraying the phase composition of Al2O3 coatings strongly depends on the degree of filling the borehole with a gas mixture. The a - Al2O3 -phase content in the coatings increases when the degree of filling is 63% and 54%. Only one CrNi3 phase is observed on the diffractograms and only increase of reflex intensity (020) at barrel filling by 58% is observed by sputtering on the bases of NiCr coatings in different degrees of barrel filling. The results of the coating nanohardness study showed that the hardness of the Al2O3 coating increases depending on the content of a- Al2O3 in it. Al2O3 coating has the maximum nanohardness values and is 16.42 GPa at the borehole is filled to 63%. The nanohardness of NiCr coating has the maximum values at barrel filling by 58% and consisting of 8.02 GPa.

Quantities and Properties of Layers Sprayed with Cored Wire of Type Fe-Cr-C

1998 ◽  
Author(s):  
H. Drzeniek ◽  
W. Milewski
Keyword(s):  
Arc Spraying ◽  
Coating Structure ◽  
Cored Wire ◽  
Spraying Parameters ◽  
Parameter Variations ◽  
Sprayed Coatings ◽  
Spraying Method

Abstract Results of macro- and microhardness investigations of newly developed coatings are presented in this paper. The coatings were produced with flame- and arc spraying technique. The coating structure and hardness is significantly influenced by the spraying method and spraying parameters. It will be shown that properties for flame sprayed coatings are more effected by parameter variations than for arc sprayed coatings. A higher hard-ness, a greater density and a better particle cohesion can be obtained by using the arc spraying method.

Thermally Sprayed Quasicrystal Composite Coatings for Bearings and Other Friction Threaded Applications

2000 ◽  
Author(s):  
E. Lugscheider ◽  
C. Herbst-Dederichs ◽  
A. Reimann
Keyword(s):  
Composite Coatings ◽  
High Hardness ◽  
Atmospheric Plasma ◽  
Ductile Material ◽  
Metallurgical Analysis ◽  
The Matrix ◽  
Material Forming ◽  
Alloy Properties ◽  
Thermally Sprayed ◽  
Sprayed Coatings

Abstract Quasicrystalline phases improve many alloy properties such as thermomechanical stability, thermal and electrical conductivity, and tribological performance. High hardness, however, is accompanied by brittleness, an undesired property in many applications. Reduced brittleness can be achieved by embedding quasicrystalline phases in a more ductile material, forming a metal-matrix composite that retains some quasicrystalline properties. This study evaluates thermally sprayed coatings made from different compositions of such composites. The coatings assessed were produced by arc-wire, HVOF, and atmospheric plasma spraying using various forms of feed material, including blended, agglomerated, chemical encased, and attrition-milled powders and filled wires. The investigation involved metallurgical analysis, proving the existence of quasicrystal content and assessing the matrix phase, and tests showing how sliding wear is influenced by the composition of quasicrystalline phases.

scholarly journals Effect of structure on properties of Al2O3 and Al (or Ti) mechanical mixture coatings produced by multichamber detonation spraying method

2017 ◽  
Vol 2017 (9) ◽  
pp. 33-39
Author(s):  
L.I. Markashova ◽  
◽  
Yu.N. Tyurin ◽  
O.V. Kolisnichenko ◽  
E.N. Berdnikova ◽  
...  
Keyword(s):  
Mechanical Mixture ◽  
Detonation Spraying ◽  
Spraying Method ◽  
Effect Of Structure

scholarly journals STRUCTURAL DEVELOPMENT AND RESEARCH OF TECHNOLOGICAL PARAMETERS OF MACHINES FOR CENTRIFUGAL -PLANETARY VIBRATION TREATMENT

2020 ◽  
pp. 41-50
Author(s):  
Leonid Yaroshenko ◽  
Igor Kupchuk ◽  
Mykhailo Zamrii
Keyword(s):  
High Efficiency ◽  
Metal Removal ◽  
Three Dimensional ◽  
High Hardness ◽  
Working Environment ◽  
Repeated Loading ◽  
Structural Development ◽  
Technological Parameters ◽  
Advantages And Disadvantages ◽  
Wide Range

The paper analyzes current state and prospects of further development of technology and equipment for mechanization and automation of finishing and cleaning of details. It is stated that the most effective for this purpose are the methods of abrasive machining, which include bulk galvanizing, vibration, centrifugal-rotary and centrifugal-planetary processing. These methods reduce the complexity and cost of processing, which in some cases reaches 20% of the total cost of manufacturing parts. Each of these methods has a different level of efficiency, certain advantages and disadvantages, the level of versatility and scope of effective application. The processes of vibration processing are quite deeply studied, for its industrial mass-produced technological equipment, but they have certain shortcomings that limit their use for further widespread implementation. Centrifugal-rotary processing is a more productive process of three-dimensional finishing and cleaning treatment, but its scope is limited by the possibility of processing parts that are not complex, usually flat. The most productive methods of finishing and cleaning of details include centrifugal-planetary volume processing which high efficiency is caused by repeated loading of particles of working load by inertial forces that creates preconditions for the solutions of a wide range of technological problems, for example, processing of details of difficult form, small weight and the sizes from materials of high hardness or viscosity that represents a serious problem for other methods of volume processing. The constructive scheme is offered in the work and the influence of the composition of the abrasive free-granular working environment on the productivity of the machine for centrifugal-planetary processing of details is investigated. The kinetics of metal removal from the surface of machined parts using different types of abrasive working environment is analyzed. The results of comparative machining of parts in a torus vibrating machine and a machine for centrifugal-planetary machining are given. It is shown that the simultaneous use of centrifugal-planetary and vibration processing methods allows to increase the intensity of the process while ensuring high quality machining of parts of relatively complex shape. The constructive scheme of the machine which allows to implement the specified combined method of processing is offered and described.

Cavitation Resistant Thermal Spray Coatings on Diesel Engine Parts

2000 ◽  
Author(s):  
Y. Borisov ◽  
V. Bogush
Keyword(s):  
Nickel Alloys ◽  
Cavitation Erosion ◽  
Thermal Spraying ◽  
Spray Coatings ◽  
Steel Wires ◽  
Mechanical Mixtures ◽  
Cored Wires ◽  
Sprayed Coatings ◽  
Spraying Method ◽  
Thermal Sprayed Coatings

Abstract This work is devoted to the study of peculiarities of thermal sprayed coatings behavior under conditions of cavitation, as well as the elaboration of compositions of cavitation-resistant coatings and technology for their application with the aim of engine cylinders sleeves protection from cavitation-erosion destruction. The methods of arc metallization, flame and plasma spraying were used for coatings deposition. Powders of metal alloys and oxides, mechanical mixtures of nickel alloys with carbides, wires and flux-cored wires were applied as materials for thermal spraying. Method of magneto-striction vibration was used to determine the coatings cavitation resistance. A correlation between a bond strength of coatings and the character of their cavitation destruction was established. The best results were obtained in the case of using stainless steel wires and flux-cored wires using. Resistance of coated diesel engines sleeves was increased 1.6 times in comparison with sleeves without coatings. Semi-automatic line for arc metallization of diesel sleeves with a production of 600,000 sleeves per year was designed, build up and put into operation.

Modeling Technological Parameters for Producing Combined Electrospark Deposition Coatings

2019 ◽  
Vol 968 ◽  
pp. 131-142 ◽  
Author(s):  
Viacheslav Tarelnyk ◽  
Ievgen Konoplianchenko ◽  
Nataliia Tarelnyk ◽  
Aleksey Kozachenko
Keyword(s):  
Electrode Materials ◽  
Protective Coatings ◽  
High Hardness ◽  
Mass Transfer Process ◽  
Electrode Pair ◽  
Surface Plastic ◽  
Technological Parameters ◽  
Electrospark Deposition ◽  
Wear Resistant

The paper represents a formalized methodology for solving the problem of creating fundamentally new materials, such as "base - coating" ones, which have increased surface wear resistance and relatively high strength and viscosity. Electrospark alloying (ESA) method is proposed as a process for depositing protective coatings on metal surfaces. There are considered the issues of improving the quality of the coatings formed by the ESA method. There is specified a feature of processing the surfaces having been treated with the use of the ESA method, which feature being associated with a relatively small thickness of the layers formed (tens of micrometers). Since to reduce the roughness of the surface, the process of grinding is difficult or even unacceptable to perform, it has been suggested to use the method of surface plastic deformation (SPD). One of the effective SPD methods for finishing the parts is a diamond smoothing process, which, in contrast to running-in with a ball or roller, allows processing the parts of very high hardness values. As a reserve to improve the quality of coatings formed by the ESA method, there is considered a process for producing combined electrospark deposition coatings (CEC) with hard wear-resistant and soft anti-friction metals integrated therein. There are represented the results of mass transfer process investigation performed at forming the CEC on the specimens of steel 45 with indium, tin and copper being used as soft antifriction metals, and tungsten and hard alloy of VK8 grade applied as wear-resistant materials. There is represented a mathematical model for calculating the main ESA technological parameters being necessary for forming the CEC and allowing to predict the weight gain (increase in weight) and size gain (increase in size) at the cathode (the part). It allows predicting the CEC main technological parameters for any electrode pair materials (substrate material and electrode materials making up the CEC).

Effect of Annealing Treatment on the Structure and Microhardness of Cold-Sprayed Nanostructured FeAl/WC Composite Coating

2008 ◽  
Vol 373-374 ◽  
pp. 73-76 ◽  
Author(s):  
Hong Tao Wang ◽  
Guan Jun Yang ◽  
Chang Jiu Li ◽  
Cheng Xing Li
Keyword(s):  
Solid Solution ◽  
Annealing Time ◽  
Composite Coatings ◽  
Annealing Treatment ◽  
Nanocrystalline Structure ◽  
Intermetallic Phases ◽  
Coating Structure ◽  
Intermetallic Composite ◽  
Sprayed Coating ◽  
Sprayed Coatings

Nanostructured FeAl/WC intermetallic composite coatings were prepared by cold spaying of the ball-milled powders. The effect of annealing on the coating structure and microhardness was examined. It was found that the nanocrystalline structure of the milled feedstock was retained in the cold sprayed coatings. The FeAl intermetallic phases were formed from the milled Fe(Al) solid solution during the post-spraying annealing at 550oC. The microhardness of the as-sprayed coating was about 680HV0.1 and it decreased a little with increasing the annealing time at 550oC.

The Influence of Some Technological Parameters on the Fracture Toughness of Ceramic Materials

2010 ◽  
Vol 446 ◽  
pp. 11-21
Author(s):  
Viorel Goanta ◽  
Marian Mares
Keyword(s):  
Fracture Toughness ◽  
Low Cost ◽  
High Hardness ◽  
Fem Analysis ◽  
Ceramic Materials ◽  
Indentation Load ◽  
Test Material ◽  
Vickers Indentation ◽  
Technological Parameters ◽  
Material Fracture

In order to determine the fracture toughness of the materials presenting high hardness values in the superficial layers, the Vickers micro-indentation was imposed as a reliable procedure. That method became attractive because of the relative simplicity of the experimental technique and because of its low cost. There are several calculus relationships that could be applied using the data provided by that method, in order to determine the material fracture toughness. The determination of fracture toughness using the Vickers indentation method is based on the analysis of radial cracks propagation, from the corners of the indentation trace. The length of these cracks is connected with the material fracture toughness, on the basis of some semi-empirical calculus relations that are taking into account the indentation load and some physical characteristics of the test material, as Young’s modulus and Poisson’s coefficient. In the present paper, fracture toughness was determined on a series of ceramic samples, made of the same material, but with different geometrical shapes and obtained by applying different technological procedures. The influence of some technological parameters on the fracture toughness was evaluated. The material fracture toughness was determined, into the vicinity of the propagated cracks (in a sample that could be a final product), on an area with a specified geometric contour. As a preliminary stage, a step by step FEM analysis was made, into the Vickers indentation material region, for different values of indentation load. In this manner, it was proved that the maximum stress value, on the perpendicular direction, as related to the crack diagonal plane, is always located at the peak of the indentation trace, and that is the effective start-point of cracking, for this type of indentation.

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