scholarly journals Microstructure, Microhardness, Corrosion Resistance and Chemical Composition of Mo, B and Mo-B Coatings Produced Using Laser Processing

Materials ◽  
2020 ◽  
Vol 13 (15) ◽  
pp. 3249 ◽  
Author(s):  
Aneta Bartkowska ◽  
Dariusz Bartkowski ◽  
Mikołaj Popławski ◽  
Adam Piasecki ◽  
Damian Przestacki ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Laser Beam ◽  
Cross Sections ◽  
Steel Substrate ◽  
Scanning Speed ◽  
Beam Power ◽  
Laser Alloying ◽  
Properties Of Coatings ◽  
Study Results ◽  
Steel Substrates

The paper presents study results of laser alloying of CT90 tool steel with an applied pre-coat of boron, molybdenum or a mixture of these elements. Pre-coats were applied on steel substrates in the form of a paste. The aim of the study was to investigate the microstructure, chemical and phase composition, microhardness and corrosion resistance of these newly-formed coatings. The laser alloying process was carried out using a diode laser with a nominal power of 3 kW. In this study a laser beam power of 900 W and a scanning speed of 48 mm/s were used. As a result of the laser beam action, the presence of three areas was observed in cross-sections of specimens: a remelted zone, a heat affected zone and the substrate. The properties of coatings enriched with both molybdenum and boron were better than those of the steel substrate, but only the use of a Mo-B mixture resulted in a significant improvement in microhardness and corrosion resistance.

scholarly journals Production and Properties of FeB-Fe2B-Fe3(B,C) Surface Layers Formed on Tool Steel Using Combination of Diffusion and Laser Processing

Coatings ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1130 ◽  
Author(s):  
Aneta Bartkowska
Keyword(s):  
Wear Resistance ◽  
Corrosion Resistance ◽  
Laser Beam ◽  
Tool Steel ◽  
Laser Processing ◽  
Steel Substrate ◽  
Beam Power ◽  
Slight Reduction ◽  
Laser Beam Power ◽  
Study Results

The paper presents the study results of laser remelting diffusion boronized layers produced on CT90 tool steel. A diffusion boronized layer was produced at 950 °C in a powder mixture containing boron carbide as a source of boron. A needle-like microstructure of iron boride was obtained. After diffusion boronizing, the specimens were subjected to laser processing, which was carried out using a diode laser with a nominal power of 3 kW. Three laser beam power values were applied (600, 900, and 1200 W). The aim of the study was to investigate the microstructure, microhardness, chemical, and phase composition as well as the wear and corrosion resistance of newly formed FeB-Fe2B-Fe3(B,C) layers. As a result of the laser beam interaction, the needle-like borides occurring in the subsurface zone were remelted, and three characteristic areas were obtained: the remelted zone, the heat-affected zone, and the substrate. The properties of newly formed layers have improved in comparison to diffusion boronized layers (except for corrosion resistance). It should be noted that using the highest laser beam power contributed to a slight reduction in wear resistance. Both the reduced corrosion and wear resistance were caused by greater remelting of the steel substrate and thus by the increased iron content in the formed layer.

scholarly journals Influence of Laser Cladding Parameters on Microstructure, Microhardness, Chemical Composition, Wear and Corrosion Resistance of Fe–B Composite Coatings Reinforced with B4C and Si Particles

Coatings ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 809 ◽  
Author(s):  
Dariusz Bartkowski ◽  
Aneta Bartkowska ◽  
Adam Piasecki ◽  
Peter Jurči
Keyword(s):  
Wear Resistance ◽  
Corrosion Resistance ◽  
Chemical Composition ◽  
Laser Beam ◽  
Laser Cladding ◽  
Scanning Speed ◽  
Powder Mixtures ◽  
Wear And Corrosion ◽  
Study Results ◽  
Wear And Corrosion Resistance

The paper presents the study results of a laser cladding process of C45 steel using powder mixtures. The aim of this study was to investigate the microstructure, X-ray diffraction (XRD), chemical composition (EDS), microhardness, corrosion resistance and wear resistance of the newly obtained coatings. Modified coatings were prepared using laser cladding technology. A 1 kW continuous wave Yb:YAG disk laser with a powder feeding system was applied. Two different powder mixtures as well as various laser beam parameters were used. The first powder mixture contained Fe–B, and the second mixture was Fe–B–B4C–Si. Two values of laser beam power (600 and 800 W) and three values of scanning speed (600, 800, and 1000 mm/min) were applied during the studies. As a result of the influence of the laser beam, the zones enriched with modifying elements were obtained. Based on the results of XRD, the presence of phases derived from borides and carbides was found. In all cases analyzed, EDS studies showed that there is an increased content of boron in the dendritic areas, while there is an increased silicon content in interdendritic spaces. The addition of B4C and Si improved properties such as microhardness as well as wear and corrosion resistance. The microhardness of the coating increased from approx. 400 HV to approx. 1100 HV depending on the laser parameters used. The best corrosion resistance was obtained for the Fe–B–B4C–Si coating produced using the highest laser beam scanning speed. An improvement in wear resistance can be seen after wear tests, where the weight loss decreased from about 0.08 g to about 0.05 g.

scholarly journals Microstructural and Mechanical Properties of B-Cr Coatings Formed on 145Cr6 Tool Steel by Laser Remelting of Diffusion Borochromized Layer Using Diode Laser

Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 608
Author(s):  
Aneta Bartkowska ◽  
Dariusz Bartkowski ◽  
Damian Przestacki ◽  
Jakub Hajkowski ◽  
Andrzej Miklaszewski
Keyword(s):  
Wear Resistance ◽  
Corrosion Resistance ◽  
Laser Beam ◽  
Diode Laser ◽  
Tool Steel ◽  
The Other ◽  
Beam Power ◽  
Other Hand ◽  
Laser Beam Power ◽  
Study Results

The paper presents study results focused on the microstructural, mechanical, and physicochemical properties of B-Cr coatings obtained by means of modification of diffusion borochromized layers by diode laser beam. The studies were conducted on 145Cr6 tool steel. Diffusion borochromized layers were produced at 950 °C in powder mixture containing boron carbides as a source of boron and ferrochrome as a source of chromium. In the next step these layers were remelted using laser beam. Powers: 600, 900, and 1200 W were used during these processes. The microstructure, microhardness, chemical composition, as well as wear and corrosion resistance of newly-formed B-Cr coatings were determined. As a result of laser beam interaction, the diffusion borochromized layer was mixed with the steel substrate. The study showed that too low laser beam power causes cracks in the newly formed B-Cr coating, and on the other hand, too higher laser beam power causes deep remelting resulting in the loss of microhardness. The reduced corrosion resistance in comparison with diffusion borochromized layers was caused by occurrence cracks or deep remelting. For B-Cr coatings produced using laser beam power 600 W, a small decrease in wear resistance was observed, but note that this coating was much thicker than diffusion borochromized layers. On the other hand, laser beam power of 1200 W caused a significant decrease in wear resistance. Newly formed B-Cr coatings had an advantageous microhardness gradient between the layer and the substrate.

scholarly journals Characterization of laser-borided Nimonic 80A-alloy

2018 ◽  
Vol 188 ◽  
pp. 02003 ◽  
Author(s):  
Piotr Kieruj ◽  
Natalia Makuch ◽  
Mateusz Kukliński
Keyword(s):  
High Temperature ◽  
Laser Beam ◽  
Laser Scanning ◽  
Scanning Speed ◽  
Beam Power ◽  
High Tech ◽  
Beam Diameter ◽  
Laser Alloying ◽  
Wear Protection ◽  
Nimonic 80A

Nimonic 80A-alloy belongs to Nickel-based superalloys. Many of them are used in variety branches of industry due to high strength and resistance in aggressive conditions. Moreover, its mechanical properties are kept in high temperature. However, these materials should be coated by appropriate wear protection, under conditions of considerable mechanical wear. Unfortunately, the production of thick borided layer in diffusion boriding required high temperature and long duration of this processes. Therefore, in this study instead conventional diffusion process laser boriding was applied in order to produce boride layer on Nimonic 80A-alloy substrate. Laser alloying is the high-tech process which allows to modify the chemical composition of the surface. Laser boriding was arranged as a single tracks, therefore it was possible to evaluate the influence of laser treatment parameters on thickness and hardness of produced layers. The laser beam power P, laser scanning speed vl and laser beam diameter dl were the variable parameters used during laser alloying.

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.

scholarly journals Fabrication and Characterization of Zein/Hydroxyapatite Composite Coatings for Biomedical Applications

Surfaces ◽  
2020 ◽  
Vol 3 (2) ◽  
pp. 237-250 ◽  
Author(s):  
Yusra Ahmed ◽  
Muhammad Yasir ◽  
Muhammad Atiq Ur Rehman
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Biomedical Applications ◽  
Steel Substrate ◽  
Composite Coatings ◽  
Sem Images ◽  
Taguchi Design Of Experiments ◽  
Hydrophilic Nature ◽  
Strong Adhesion ◽  
Steel Substrates

Stainless steel is renowned for its wide use as a biomaterial, but its relatively high corrosion rate in physiological environments restricts many of its clinical applications. To overcome the corrosion resistance of stainless steel bio-implants in physiological environments and to improve its osseointegration behavior, we have developed a unique zein/hydroxyapatite (HA) composite coating on a stainless steel substrate by Electrophoretic Deposition (EPD). The EPD parameters were optimized using the Taguchi Design of experiments (DoE) approach. The EPD parameters, such as the concentration of bio-ceramic particles in the polymer solution, applied voltage and deposition time were optimized on stainless steel substrates by applying a mixed design orthogonal Taguchi array. The coatings were characterized by using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and wettability studies. SEM images and EDX results indicated that the zein/HA coating was successfully deposited onto the stainless steel substrates. The wettability and roughness studies elucidated the mildly hydrophilic nature of the zein/HA coatings, which confirmed the suitability of the developed coatings for biomedical applications. Zein/HA coatings improved the corrosion resistance of bare 316L stainless steel. Moreover, zein/HA coatings showed strong adhesion with the 316L SS substrate for biomedical applications. Zein/HA developed dense HA crystals upon immersion in simulated body fluid, which confirmed the bone binding ability of the coatings. Thus the zein/HA coatings presented in this study have a strong potential to be considered for orthopedic applications.

scholarly journals Influence of SiO2 Content and Exposure Periods on the Anticorrosion Behavior of Epoxy Nanocomposite Coatings

Coatings ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 118 ◽  
Author(s):  
Alam ◽  
Samad ◽  
Sherif ◽  
Poulose ◽  
Mohammed ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
High Performance ◽  
Electrochemical Impedance ◽  
Steel Substrate ◽  
Sio2 Nanoparticles ◽  
Epoxy Coating ◽  
Properties Of Coatings ◽  
Ft Ir ◽  
Eis Measurements ◽  
Coating Formulations

Epoxy coating formulations containing 1%, 3%, and 5% SiO2 nanoparticles were produced and applied on a mild steel substrate to achieve the objective of high performance corrosion resistance. The electrochemical impedance spectroscopy (EIS) technique was employed to measure the anticorrosive properties of coatings. The corrosion tests were performed by exposing the coated samples in a solution of 3.5% NaCl for different periods of time, varied from 1 h and up to 30 days. Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) analyses revealed the presence of nanoparticles in the final cured samples. Establishing the incorporation of the nanoparticles in the coating formulations was confirmed by employing both of XRD and FT-IR techniques. The FT-IR spectra have proved to be satisfactory indicating that there was a complete reaction between the epoxy resin with the hardener. EIS measurements confirmed that the presence and the increase of SiO2 nanoparticles greatly improved the corrosion resistance of the epoxy coating. The highest corrosion resistance for the coatings was obtained for the formulation with 5% SiO2 nanoparticles content, particularly with prolonging the immersion time to 30 days.

scholarly journals Manufacturing Technology and Properties of Fe/TaC Metal Matrix Composite Coatings Produced on Medium Carbon Steel Using Laser Processing—Preliminary Study on the Single Laser Tracks

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5367
Author(s):  
Dariusz Bartkowski
Keyword(s):  
Laser Beam ◽  
Metal Matrix Composite ◽  
Matrix Composite ◽  
Laser Processing ◽  
Metal Matrix ◽  
Steel Substrate ◽  
Composite Coatings ◽  
Tantalum Carbide ◽  
Beam Power ◽  
Laser Beam Power

The paper presents study results of Fe/TaC metal matrix composite coatings produced on tool steel using laser processing of TaC pre-coat. The Fe/TaC coatings were produced in two steps. First, a pre-coat in the form of a paste based on tantalum carbide and water glass was made and then applied to the steel substrate. In the second step, the TaC pre-coat was remelted with steel substrate using a diode laser beam with a rated power of 3 kW. A constant scanning speed of the laser beam of 3 m/min and three types of laser beam power: 500 W, 800 W and 1100 W were applied. Tests were carried out on three different thicknesses of the TaC pre-coat: 30 µm, 60 µm and 90 µm. The influence of pre-coat thickness and laser beam power on the microstructure, chemical composition and microhardness were analyzed. A possibility of producing coatings with a characteristic composite structure was found, where the iron from the substrate became the matrix, and the introduced tantalum carbides—the reinforcing phase. It was found that too high power of the laser beam leads to complete melting of the introduced primary TaC particles. It was also found that the use of a thicker TaC pre-coat contributes to microhardness increase.

scholarly journals Microstructure, phase composition and corrosion resistance of Ni2O3 coatings produced using laser alloying method

2016 ◽  
Vol 36 (1) ◽  
pp. 23-29 ◽  
Author(s):  
Aneta Bartkowska ◽  
Damian Przestacki ◽  
Tadeusz Chwalczuk
Keyword(s):  
Corrosion Resistance ◽  
Surface Layer ◽  
Phase Composition ◽  
Laser Beam ◽  
Nickel Oxide ◽  
Heat Affected Zone ◽  
Laser Alloying ◽  
Nickel Oxides ◽  
Thickness Increase ◽  
Good Corrosion Resistance

Abstract The paper presents the studies' results of microstructure, microhardness, cohesion, phase composition and the corrosion resistance analysis of C45 steel after laser alloying with nickel oxide (Ni2O3). The aim of the laser alloying was to obtain the surface layer with new properties through covering C45 steel by precoat containing modifying compound, and then remelting this precoat using laser beam. As a result of this process the surface layer consisting of remelted zone and heat affected zone was obtained. In the remelted zone an increased amount of modifying elements was observed. It was also found that the surface layer formed during the laser alloying with Ni2O3 was characterized by good corrosion resistance. This property has changed depending on the thickness of the applied precoat. It was observed that the thickness increase of nickel oxides precoat improves corrosion resistance of produced coatings.

scholarly journals Study of the thermally sprayed Zn coatings in the context of use in special purpose articles

2018 ◽  
Vol 90 (11) ◽  
Author(s):  
Mariusz Bober ◽  
Rafał Milczarek ◽  
Marek Żubrowski ◽  
Wojciech Sokołowski
Keyword(s):  
Corrosion Resistance ◽  
Alloy Steel ◽  
Steel Substrate ◽  
Atmospheric Conditions ◽  
High Corrosion Resistance ◽  
Protective Layers ◽  
Operational Tests ◽  
Steel Substrates ◽  
Thermally Sprayed ◽  
Salt Fog

The paper presents the results of operational tests of thermal sprayed zinc coatingsof various thicknesses on non-alloy steel substrates. The resistance of coatings to:variable temperature cycles, increased ambient humidity, salt fog as well as the electri-cal resistance of the coating and its adhesion to the steel substrate were tested. It hasbeen shown that Zn coatings has a high corrosion resistance in various atmospheric conditions and have satisfactory properties so they can be protective layers of ma-chine parts used in the armaments industry.

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