scholarly journals Influence of Chromium Concentration on the Abrasive Wear of Ni-Cr-B-Si Coatings Applied by Supersonic Flame Jet (HVOF)

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 915
Author(s):  
Mara Kandeva ◽  
Zhetcho Kalitchin ◽  
Yana Stoyanova
Keyword(s):  
Wear Resistance ◽  
Thermal Treatment ◽  
Composite Coatings ◽  
Research Work ◽  
High Hardness ◽  
Wear Intensity ◽  
Chromium Concentration ◽  
Preliminary Thermal Treatment ◽  
Cr Concentration ◽  
Pin On Disk

This research work studies the characteristics of wear and wear resistance of composite powder coatings, deposited by supersonic flame jet (HVOF), which contain composite mixtures Ni-Cr-B-Si having different chromium concentrations—9.9%, 13.2%, 14%, 16%, and 20%, at one and the same size of the particles and the same content of the remaining elements. The coating of 20% Cr does not contain B and Si. Out of each powder composite, coatings have been prepared without any preliminary thermal treatment of the substrate and with preliminary thermal treatment of the substrate up to 650 °C. The coatings have been tested under identical conditions of dry friction over a surface of solid, firmly-attached, abrasive particles using tribological testing device “Pin-on-disk”. Results have been obtained and the dependences of the hardness, mass wear, intensity of the wearing process, and absolute and relative wear resistance on the Cr concentration under identical conditions of friction. It has been found out that for all the coatings the preliminary thermal treatment of the substrate leads to a decrease in the wear intensity. Upon increasing Cr concentration the wear intensity diminishes and it reaches minimal values at 16% Cr. In the case of coatings having 20% Cr concentration, the wear intensity is increased, which is due to the absence of the components B and Si in the composite mixture, whereupon no inter-metallic structures are formed having high hardness and wear resistance. The obtained results have no analogues in the current literature and they have not been published by the authors.

scholarly journals Influence of Chromium Concentration on the Abrasive Wear Of Ni-Cr-B-Si Coatings Applied by High-Velocity Oxygen Fuel

2021 ◽  
Author(s):  
Zhetcho Doinov Kalitchin ◽  
Mara Krumova Kandeva ◽  
Yana Petrova Stoyanova
Keyword(s):  
Wear Resistance ◽  
Thermal Treatment ◽  
High Velocity ◽  
Composite Coatings ◽  
Research Work ◽  
Wear Intensity ◽  
High Velocity Oxygen Fuel ◽  
Preliminary Thermal Treatment ◽  
Cr Concentration ◽  
Oxygen Fuel

This research work studies the characteristics of wear and wear resistance of composite powder coatings, deposited by high-velocity oxygen fuel, which contain composite mixtures Ni-Cr-B-Si having different chromium concentrations – 9.9%; 13.2%; 14%; 16% and 20% , at one and the same size of the particles and the same content of the remaining elements. The coating of 20% Cr does not contain B and Si. Out of each powder, composite coatings have been prepared without any preliminary thermal treatment of the substrate and with preliminary thermal treatment of the substrate up to 650оС. The coatings have been tested under identical conditions of dry friction over a surface of solid firmly attached abrasive particles using the tribological testing device „Pin-on-disk“. Results have been obtained and the dependences of the hardness, mass wear, intensity of the wearing process, absolute and relative wear resistance on the Cr concentration under identical conditions of friction. It has been found out that for all the coatings the preliminary thermal treatment of the substrate leads to a decrease in the wear intensity. Upon increasing Cr concentration the wear intensity diminishes and it reaches minimal values at 16% Cr. In the case of coatings having 20% Cr concentration, the wear intensity is increased, which is due to the absence of the components B and Si in the composite mixture, whereupon no inter-metallic structures are formed having high hardness and wear resistance. The obtained results have no analogues in the current literature and they have not been published by the authors.

Wear Studies of Al2O3-ZrO2∙5CaO Composite Coatings for Tribological Applications

2018 ◽  
Vol 7 (3.4) ◽  
pp. 73
Author(s):  
Abhinav . ◽  
N Krishnamurthy ◽  
Ranjana Jain
Keyword(s):  
Composite Coatings ◽  
Spray Coating ◽  
High Hardness ◽  
Xrd Analysis ◽  
Atmospheric Plasma ◽  
Crystallographic Structure ◽  
The Coefficient Of Friction ◽  
Sem Micrograph ◽  
Composite Mixture ◽  
Pin On Disk

A composite mixture of Metco 105 SFP, 99.9% Al2O3 and Metco 201 NS, ZrO2.5CaO were blended in the pursuit of high hardness and improved wear resistance characteristics for tribological applications. In this context a composite mixture of alumina and calcia stabilized zirconia in 50:50 by wt. % proportion was developed, and applied over Al-6061 substrates. Atmospheric plasma spray coating technique was used to develop the coating systems. The ASTM G132 standard, a pin-on-disk tribometer was used to determine the specific wear rate at different normal loads of 5 N, 10 N and 15 N. Experimental results revealed that the top coat primarily subjected to sliding and localized abrasion and also confirmed with SEM micrograph. Sliding has mainly occurs in the plane of <111>, <200>, <220>, <311>, <222> found in the XRD analysis. Irrespective of the applied normal loads the coefficient of friction doesn’t influences much in the abrasive wear studies. However, wear mechanism was found to primarily dependent on the phases and on the crystallographic structure of the material used.  

scholarly journals Abrasive wear resistance of selected woods

2017 ◽  
Vol 63 (No. 2) ◽  
pp. 91-97
Author(s):  
Brožek Milan
Keyword(s):  
Wear Resistance ◽  
Abrasive Wear ◽  
Sweet Cherry ◽  
Sour Cherry ◽  
Wear Intensity ◽  
Horse Chestnut ◽  
Silver Fir ◽  
Abrasive Particles ◽  
Volume Weight ◽  
Pin On Disk

In this contribution, the results of the wear resistance study of 10 sorts of wood (apple, aspen, beech, hornbeam, horse-chestnut, London plane, mahogany, silver fir, sour cherry and sweet cherry) are published. The laboratory tests were carried out using the pin-on-disk machine when the abrasive clothes of three different grits (240, 120 and 60) were used. The wear intensity was assessed by the volume, weight and length losses of the tested samples. From the results of the carried out tests it follows that the wear resistance of different woods is different. It was proved that the wear resistance of different woods depends on the abrasive particles size, too. Also the technical-economical evaluation was part of the carried out tests. It was univocally proved that at the intensive abrasive wear using the abrasive cloth the best results were shown by hard woods, e.g. apple, beech or mahogany. Soft woods, e.g. horse-chestnut, silver fir or sweet cherry, are cheap, but their wear is bigger compared to hard woods.

Laser Cladding of Ni60/WC/TiN Composite Coatings on 00Cr13Ni4Mo Hydro Turbine Blade Stainless Steel for Improvement of Wear Resistance

2012 ◽  
Vol 430-432 ◽  
pp. 101-105
Author(s):  
Kai Jin Huang ◽  
Hua Rui Jiang ◽  
Xin Lin
Keyword(s):  
Stainless Steel ◽  
Wear Resistance ◽  
Turbine Blade ◽  
Laser Cladding ◽  
Composite Coatings ◽  
High Hardness ◽  
Dry Sliding Wear ◽  
Wear Property ◽  
Hydro Turbine ◽  
Wear Condition

To improve the wear property of 00Cr13Ni4Mo hydro turbine blade stainless steel, Ni-based composite coatings were fabricated on 00Cr13Ni4Mo stainless steel by laser cladding using mixed powders of Ni60, WC and TiN. The microstructure of the coatings was characterized by XRD and SEM techniques. The wear resistance of the coatings was evaluated under dry sliding wear condition at room temperature. The results show that the coatings mainly consist of Ni-based solid solution, WC and TiN phases. The coatings exhibit excellent wear resistance due to its high hardness of WC and TiN phases. The main wear mechanisms of the coatings and the 00Cr13Ni4Mo sample are different, the former is abrasive wear and the latter is adhesive wear.

The Effect of Processes Parameters on the Abrasive Wear Resistance of Boronized AISI 1050 Steel

2016 ◽  
Author(s):  
Mete Han Boztepe ◽  
Melih Bayramoglu
Keyword(s):  
Wear Resistance ◽  
Abrasive Wear ◽  
Mesh Size ◽  
High Hardness ◽  
High Strength ◽  
Constant Load ◽  
Abrasive Wear Resistance ◽  
Wear Testing ◽  
Wear Properties ◽  
Pin On Disk

Boronizing is one of the thermochemical surface treatment processes which is extensively used to obtain excellent mechanical properties such as high strength, very high hardness, good toughness and fracture toughness. In this study, AISI 1050 steel specimens have been subjected to pack boronizing process by using Ekabor 2 powder within the stainless steel seal container. The experiments were carried out at temperatures of 800 °C, 850 °C and 900 °C for 3, 6 and 9 hours to investigate the effect of these parameters on the wear resistance of boronized specimens. Pin-on-Disk wear testing is used to characterize wear properties of boronized specimens. Wear tests were performed at dry conditions under constant load of 30 N by using 220 mesh size Al2O3 abrasive paper. Different rotating speeds of the pin-on disk were selected as 300, 600, 900, 1200, 1500 revolutions for each of the test specimens. After the abrasive tests, weight losses of the specimens were measured to determine the abrasive wear resistance of boronized specimens. The results were also compared with unboronized and conventional hardened AISI 1050 steel specimens respectively.

scholarly journals Microstructure and Wear Behavior of In-Situ NbC Reinforced Composite Coatings

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3459 ◽  
Author(s):  
Baoming Shi ◽  
Shiming Huang ◽  
Ping Zhu ◽  
Changen Xu ◽  
Tengfei Zhang
Keyword(s):  
Wear Resistance ◽  
Composite Coating ◽  
Wear Behavior ◽  
Composite Coatings ◽  
Niobium Carbide ◽  
Low Carbon Steel ◽  
High Hardness ◽  
Low Carbon ◽  
Micro Hardness

In the present study, plasma spray welding was used to prepare an in-situ niobium carbide (NbC) reinforced Ni-based composite coating on the low carbon steel, and the phase composition and the microstructure of the composite coatings were studied. The wear resistance and the wear mechanism of the composite coatings were also researched by the wear tests. The results showed that the main phases of the composite coating were NbC, γ-Ni, Cr23C6, Ni3Si, CrB, Cr5B3, Cr7C3 and FeNi3. A number of fine in-situ NbC particles and numerous chromium carbide particles were distributed in the γ-Ni matrix. The increase in the mass fraction of Nb and NiCr-Cr3C2 could lead to the increase in NbC particles in the composite coatings. Due to the high hardness of NbC and chromium carbides, the micro-hardness and the wear resistance of the composite coatings were advanced. The composite coating with the powder mixtures of 20% (Nb + NiCr-Cr3C2) and 80% NiCrBSi had the highest micro-hardness and the best wear resistance in this study. The average micro-hardness reached the maximum value 1025HV0.5. The volume loss was 39.2 mm3, which was merely 37% of that of the NiCrBSi coating and 6% of that of the substrate under the identical conditions.

Wear Resistance of Laser Alloyed ZrB2 Coatings on Mild Steel

2000 ◽  
Author(s):  
A. Gadkari ◽  
A.S. Khanna ◽  
N.B. Dahotre
Keyword(s):  
Wear Resistance ◽  
Mild Steel ◽  
High Hardness ◽  
Laser Alloying ◽  
Temperature Oxidation ◽  
Wear And Corrosion ◽  
Wear And Corrosion Resistance ◽  
Xrd Techniques ◽  
Beam Directionality ◽  
Pin On Disk

Abstract Borides are promising materials with good wear and corrosion resistance properties. Boride coatings are expected to perform better where wear and corrosion resistances are simultaneously required. Zirconium diboride is an important emerging material for such applications, due to its high hardness, high melting point, good wear resistance and corrosion as well as high temperature oxidation resistance. Special properties of laser beam like beam directionality, high intensity and spatial resolution makes laser alloying a fast and efficient technique for producing improved wear resistance coatings. In the present work, mild steel was laser alloyed with ZrB2, using "two-stage" technique of laser alloying. These coatings after characterization by optical microscopy, SEM, EDAX and XRD techniques were tested on a "Pin-on-Disk" machine for determining their wear resistance.

ELECTRIDEPOSITION AND WEAR BEHAVIOR OF NANO-STRUCTURED Cr-WC COMPOSITE COATINGS FROM A TRIVALENT CHROMIUM BATH

2012 ◽  
Vol 05 ◽  
pp. 737-743 ◽  
Author(s):  
A. AMADEH ◽  
S. NADALI ◽  
S.M. LARI BAGHAL ◽  
H. MORADI
Keyword(s):  
Wear Resistance ◽  
Current Density ◽  
Duty Cycle ◽  
Wear Behavior ◽  
Composite Coatings ◽  
Sodium Dodecyl ◽  
Trivalent Chromium ◽  
Sodium Saccharin ◽  
Average Size ◽  
Pin On Disk

Electrodeposition of nano-structured Cr - WC had been carried out from a trivalent chromium bath using a square shaped pulse current. The average size of WC particles was 70 nm. The effect of sodium saccharin and sodium dodecyl sulfate (SDS) additives as well as pulse electroplating parameters such as current density, duty cycle and frequency on the amount of incorporated WC particles and morphology of the coatings was investigated. The structure and morphology of the coatings were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. In addition, the hardness and tribological behavior of the coatings were investigated by microhardness and pin on disk methods, respectively. The results showed that although the addition of saccharin and SDS decreased the amount of WC particles in the coating, but reduced the size of WC agglomerates which, in turn, increased the wear resistance of the coatings. Also, the optimum wear resistance was achieved at the current density of 8 A/dm2, duty cycle of 50% and frequency of 10 Hz.

Mechanical and Corrosion Behavior of TiN Coatings Deposited on Nitrided AISI 420 Stainless Steel

2019 ◽  
Vol 813 ◽  
pp. 135-140
Author(s):  
Eugenia Laura Dalibon ◽  
Amado Cabo ◽  
Jorge Halabi ◽  
Ramiro D. Moreira ◽  
Kevin Silva ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Wear Resistance ◽  
Corrosion Behavior ◽  
Nitrided Layer ◽  
Salt Spray ◽  
High Hardness ◽  
Wear Loss ◽  
Tin Coating ◽  
Tin Coatings ◽  
Pin On Disk

TiN coatings are widely used in different applications for extending the lifetime of components due to their high hardness and good wear resistance. However, it is not convenient to deposit them on soft stainless steels. In this work, the wear and corrosion behavior of commercial TiN coatings deposited by Arc-PVD on nitrided and non-nitrided martensitic stainless steel was studied. Two different nitriding conditions were used, one at high temperature (HTN) and the other at low temperature (LTN). Nanohardness and microhardness were measured. The microstructure was characterized by OM, SEM, XRD and XPS. Pin on disk and erosion tests were carried out in order to evaluate their wear resistance. The corrosion behavior was analyzed in salt spray fog and electrochemical tests in NaCl solution and the adhesion was measured in Scratch and Rockwell C Indentation tests.The coating thickness was about 1.5 µm and its hardness of 34 GPa. The nitrided layers were 13 µm and 17 µm thick for LTN and HTN, the hardness was approximately 12 GPa for both nitrided samples. The nitrided layer improved TiN coating adhesion in the Scratch tests. The wear loss volume was similar for both duplex and only coated samples in pin on disk tests. Nevertheless, wear resistance was not good for the LTN or HTN + TiN coating system in the erosion tests. Regarding corrosion behavior, the coatings showed poor corrosion resistance and this could be related to the presence of porous defects, which allow the solution to reach and attack the substrate, thus producing coating detachment around the pits.

Wear Resistance of Experimental Hard Alloys Grades with Co-Mo-Ti Binders upon Conditions of Friction without Lubricant on Stainless Steel

2021 ◽  
Vol 1037 ◽  
pp. 522-527
Author(s):  
Evgeny V. Fominov ◽  
Maxim S. Egorov ◽  
Denis V. Moiseev ◽  
E. Dieudonne ◽  
Constantine G. Shuchev
Keyword(s):  
Stainless Steel ◽  
Wear Resistance ◽  
Normal Load ◽  
Wear Intensity ◽  
Partial Substitution ◽  
Hard Alloys ◽  
Adhesive Interaction ◽  
Volume Wear ◽  
Shielding Properties ◽  
Pin On Disk

The results of studies of wear resistance and tribological properties of experimental single carbide hard alloys grades with modified Co-Mo-Ti binders upon conditions of friction without lubricant on stainless steel are presented. All the data obtained were compared with similar parameters for the basic alloy VK8 (Co-Mo), on the basis of which the experimental grades were developed. Tribological tests were performed on tribometer which implemented a scheme of friction "pin on disk" at constant sliding speed and normal load values with artificially heated tribo contact zone. Studies have found that partial substitution of cobalt in a binder by Mo and Ti has led to a decrease in average friction rates. It was established that the greatest wear resistance and the best tribological characteristics were obtained for specimens of experimental grade 2.22 (5,65%Co+1,8%Mo+0,6%Ti). The process of friction for this pin material was characterized by the formation of secondary structures with high shielding properties, reducing of the adhesive interaction of materials, low volume wear intensity, minimal friction coefficient, as well as the least roughness of friction tracks on the counter body (disk). An increase in the proportion of molybdenum in the binder of more than 5% reduced the wear resistance of the experimental grades in comparison with the basic alloy VK8.

Sign in / Sign up

Export Citation Format

Share Document