Arc Cladding Research Articles

Microstructure and properties of argon arc cladded CoCr x FeMoNiAl high entropy alloy coatings on Q235 steel

Abstract In this paper, the CoFeMoNiAlCr x coatings with different chromium content (x = 0, 0.3, 0.6, 0.9 and 1.2) were prepared by argon arc cladding technology on Q235 steel. The microstructure and phases of the coatings were analyzed by OM, SEM, EDS and XRD. The hardness, wear resistance and corrosion resistance of the coatings were tested by microhardness tester, friction and wear tester and electrochemical workstation. The results show that the highest hardness is obtained in the CoFeMoNiAlCr x=0 high entropy alloy coatings, about 500 HV, which is about 3 times than the hardness of Q235 steel (the substrate). With the chromium content of the CoFeMoNiAlCr x coatings increasing, the wear resistance increases first, and then decreases. When the chromium content is 0.9, the wear resistance of the coating is the highest with the wear loss about 2.6 mg and the friction coefficient about 0.52. The corrosion resistance of the coatings decreases with a small amount of chromium addition. When the Cr content in the coating is close to the atomic ratio, the content of the body-centered cubic phase structure increases, and the face-centered cubic phase structure appears in the coating.

Plasma Transferred Arc Cladding of an H13 Tool Steel Modified with a CoCrFeMnNi High Entropy Alloy.

Plasma Transferred Arc Cladding of an H13 Tool Steel Modified with a CoCrFeMnNi High Entropy Alloy.

Effect of rare earth oxide (Y2O3) addition on wear characteristic of TiB2 ceramic reinforced Mo-based composite coating fabricated by Argon shielded Arc cladding

In this study, Mo-based composite coatings with 1 wt.% of rare Earth oxide (Y2O3) contents were successfully manufactured on AISI SS304 (stainless steel) by argon shielded arc (ASAC) cladding method. The effect of Y2O3 on phase composition, microstructure, mechanical and tribological properties of Mo-based coatings were investigated by x-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM) with energy dispersive x-ray spectrometer (EDS), micro-Vickers hardness apparatus and pin-on-disc type wear tester. The result demonstrates that the upper surface of composite coating with and without addition of Y2O3 were mainly comprised of TiB2, Ni3Ti, Fe3Mo, MoNi4, NiTi, Mo2B, Y2TiO7, Cr2Ti, Fe3B, Y2O3, and MoNi4 appeared. The constituent phase components in the coated layer were found to be beneficial for the enhancement of the microhardness and wear resistance. The maximum value of average micro-hardness and wear resistance was observed in samples having 1 wt.% of Y2O3 as a precursor. The average microhardness of Mo-based coatings with Y2O3 addition was in the range of 1599 to 2170.4 HV0.1 and wear resistance increases from 1.41 to 6.36 × 10−8 g/N-m. The pronounced effect of Y2O3 addition on microhardness and wear resistance of coatings were consistent with the calculation results of applied multivariate statistical analysis. Thus, it can be concluded that the addition of Y2O3 is effective and achievable way to solidate hardness and wear resistance of Mo-based coatings.

Sedimentation suppression and precipitation regulation of WC-reinforced particles in plasma arc deposited Ni-based coatings via an alternating magnetic field

The pursuit of high quality, high efficiency, and low investment in ceramic particles reinforced Ni-based composite coating has prompted continuous advancement in surface modification technology. Herein, the WC/Ni60 coatings were prepared by a coaxial alternating magnetic field (AMF) coupled plasma arc cladding technology. The effects of AMF on the distribution of reinforcing particles and the improvement of coating quality were investigated. The results demonstrated that the AMF significantly suppressed the sedimentation behavior of WC particles within the coating, and the WC particles were dispersed and uniformly distributed under the AMF intensity of 20 mT. With the increase of the AMF intensity (10 mT–30 mT), the semi-quantitative evaluation of the combustion loss rate indicated a rise in the dissolution degree of WC particles from 10.1% to 33.4%, leading to a gradual increase in the content of precipitated carbides (i.e., M6C, M7C3) with varied morphological characteristics. AMF-induced magnetic stirring facilitated nucleation, contributing to remarkable grain refinement and an elevation in the proportion of high-angle grain boundaries. Mechanical testing witnessed that the AMF-assisted samples are superior in microhardness and wear resistance performance compared with the counterpart without AMF. In particular, the coating with AMF intensity of 20 mT exhibited the most uniform distribution of microhardness.

Effect of TiFe/Cr3C2 precursor powder ratio in in-situ synthesis of TiC-reinforced Stellite 6 coatings by PTA cladding

The copper tuyeres in blast furnaces were exposed to severe high-temperature wear during its operation, hence coating was necessary to improve its durability. This study focuses on the development of TiC-reinforced Stellite 6 alloy coatings on copper substrate. Plasma transferred arc cladding was used to prepare a series of coatings with 15 wt% TiFe/Cr3C2 powder in-situ synthesized TiC. Ni60A intermediate layers were first prepared on the copper surface followed by the TiC-reinforced Stellite 6 coatings with Ti/C ratios of 1:1, 2:1, and 3:1. The results indicate that the Ni60A intermediate layer demonstrated good bonding with the copper substrate and established a metallurgical bond with all the TiC-reinforced coatings. However, the coatings with a Ti/C ratio of 1:1 exhibited pore defects at the interface and severe adhesive wear at 500 °C. The 3:1 Ti/C coating exhibited the longest transition zone and the lowest hardness. The coatings with a Ti/C ratio of 2:1 was found to be the best ratio with a moderate transition zone and hardness, a defect-free interface, and the optimum high-temperature wear resistance. The hardness of this coating was 576.69 HV, which was 15.53 % higher than that of the Stellite 6 alloy. The wear mechanism of the T2 coating was abrasive wear and its wear resistance was 2.3, 4.1 and 4.1 times higher than that of the Stellite 6 alloy at test conditions of 25 °C, 300 °C and 500 °C respectively.

Laser beam remelting of stainless steel plate for cladding and comparison with conventional CMT process

Progressing towards circular economy requires smarter and more efficient use of energy and resources. Laser beam can be efficient and flexible tool for melting different metals, commonly used in cladding and additive manufacturing (AM) with a wire and powder feedstock. As an alternative, feedstock in the form of plates and sheets can be used for cladding to achieve corrosion resistant surfaces. Compared to powder or wire, plates are easier to process, less costly to use, and may come as scrap metal. This leads to smarter and more efficient resource utilization. However, processing plates in such way is not mature and requires more in-depth investigation to be competitive with well-established methods. In this work, 2.0 mm thick 316L stainless steel plates were remelted by a high-power fibre laser beam for cladding on carbon steel substrates. It was compared to the conventional cold metal transfer (CMT) welding-based arc cladding which is frequently used due to a low heat input. In the first phase, different defocusing distances were studied to understand the laser remelting process capabilities to optimize the productivity. It was found that a highly defocused laser beam provided unstable melt pool conditions with low track quality. Compared to CMT, the laser remelting provided enhanced productivity, reduced heat input by 50% per pass, and lower distortions. Microhardness testing showed an increase in hardness in the intermediate layer towards the fusion line due to carbon diffusion. Despite a higher delta ferrite formation in laser-remelted tracks, a comparable corrosion protection to CMT was observed. The proposed method is promising for reducing CO2 emissions with respect to reusing scrap metal in the form of plates or use of ordinary plates instead of filler wires which opens possibilities for further enhancements.

Effect of copper oxides on defect formation during PTA cladding of Stellite 6 on copper substrates

Stellite 6 coating is ideal for the protection of copper components in high-temperature environments, but the quality of the coating can be affected by the formation of copper oxide at the interface. In this study, plasma transfer arc cladding was employed to prepare Stellite 6 alloy cladding layers on copper substrates, with a preheating temperature of 700 °C and a cladding current of 120–170 A. Cladding experiments were conducted to investigate the impact of copper oxides generated during the cladding process on the quality of the cladding layer. Results showed that, when the current was below 140 A, insufficient current input caused edge cracking of the cladding layer, and the cracks tend to extend along the oxide layer at the interface. Interfacial reactions between the Stellite 6 alloy and copper oxide on the copper substrate produced CO/CO2, which led to pores forming at the interface. When the current was above 140 A, the localized overheating resulted in the upturning of the substrate, destroying the continuous copper oxide layer and eventually forming localized dents. The copper oxide affects the bonding of the cladding layer to the substrate. Increasing the cladding current helps to eliminate cracks and porosity, resulting in a good bond, but excessive current leads to localized dents. In this paper, 140 A was a relatively suitable current to produce satisfactory cladding layers. The wear resistance of the cladding layer was 1.9 and 2.2 times higher than that of the copper substrate at 25 and 300 °C, respectively.

Design, preparation, microstructure and tribological properties of Cr7C3 and CrxSy reinforced composite coating

Conventional rod pumping has been the dominant petroleum recovery technology for nearly a century. As key components of the rod pumping system, tubing and sucker rod coupling are often prematurely scrapped due to “rod/tubing eccentric wear”. To improve the service life of sucker rod coupling and tubing, a Cr7C3 and CrxSy reinforced γ-(Ni, Fe) matrix composite coating was designed by JMatPro simulation and the coating was prepared by plasma transferred arc (PTA) cladding technique. The coating has a refined microstructure composed of Cr7C3 carbide, amorphous sulfide CrxSy and γ solid solution. Primary Cr7C3 fine blocks with volume fraction up to 54% are uniformly dispersed in the coating giving the coating high hardness and good wear resistance. The in-situ synthesized CrxSy phases are dispersed in the γ matrix in the form of fine spherical particles, which endows CrxSy phases strong interfacial bonding, and allows the CrxSy particles to be stripped layer-by-layer, thereby providing continuous lubrication. The coating exhibits excellent wear resistance and low and stable friction coefficient, and is expected to serve as a protective coating for sucker rod coupling to simultaneously improve the service life of sucker rod coupling and tubing.

Firefly Algorithm and Neural Network Employment for Dilution Analysis of Super Duplex Stainless Steel Clads over AISI 1020 Steel Using Gas Tungsten Arc Process

Traditional low-carbon steels provide the strength needed to satisfy industrial demands. Low-carbon steel’s poor corrosion resistance is one of its main drawbacks. Due to this restriction, corrosion-resistant materials such as super duplex stainless steels are frequently used for cladding onto the surface of low-carbon steel. The cladded surface possesses superior chloride stress corrosion cracking resistance, pitting and crevice corrosion resistance, yield strength, ductility, and impact toughness. Mild steel with measurements of 300 × 300 × 12 mm has been selected as the substrate material, and super duplex stainless steel (S32950) with an electrode diameter of 2.4 mm has been selected as the filler wire. Gas Tungsten Arc (GTA) cladding was performed onto the surface of low-carbon steel for experimentation. The clad was deposited in the flat position with four different currents, i.e., 120 A, 130 A, 140 A, and 150 A. Cladding was performed on different layers of each current level, i.e., single layer, double layers, and triple layers. After experimenting and overviewing the outcomes, it can be concluded that the optimum input parameters would be a 3-layered clad at a 140 A current level. Cladding of the super duplex stainless steel over mild steel improves the corrosive properties. The percentage ratio of reactivation current density to activation current density (Ir/Ia%) improves from 29% (mild steel) to 4.1% at the top layer and 11.9% at the intermediate layer. The microhardness of the clad decreases with an increase in both the current level and the number of layers. Microhardness varies between 191–248 at the clad, 170–189 at the HAZ, and 143–153 at the substrate for a 1 kgf load. Dilution refers to the change in the cladding alloy composition due to the mixing of the molten matrix. The composition of the clad changes under a high dilution, resulting in a decrease in the mechanical as well as corrosion properties of the clad. However, if the dilution is too small, the bond between the substrate and the clad is poor. Therefore, dilution is one of the most important process control parameters and the key to obtaining high-quality cladding. Thus, the dilution effect is also analyzed on all three clad layers deposited at various current levels using the firefly algorithm (FA) and artificial neural network (ANN). It is observed that dilution levels are found to be more approachable to the experimental setup data with FA in comparison to ANN for various current levels.

Microstructure and Tribological Properties of Metal Layer Deposited by Arc Cladding of Powder Wire Containing Titanium Powder

Microstructure and Tribological Properties of Metal Layer Deposited by Arc Cladding of Powder Wire Containing Titanium Powder

Interfacial microstructures and infiltrated cracks in tin bronze/steel bimetallic materials fabricated by arc cladding

Interfacial microstructures and infiltrated cracks in tin bronze/steel bimetallic materials fabricated by arc cladding

Optimizing 304 Stainless Steel Surface Performance with CoCrFeMoNi High-Entropy Alloy Coating via Gas Tungsten Arc Cladding

Optimizing 304 Stainless Steel Surface Performance with CoCrFeMoNi High-Entropy Alloy Coating via Gas Tungsten Arc Cladding

In Situ Synthesis of Cr2AlC Gradient Coating by Plasma Transferred Arc Cladding

In Situ Synthesis of Cr2AlC Gradient Coating by Plasma Transferred Arc Cladding

Microstructure and wear analysis of CoWC alloy layers deposited by PTA process

CoWC composite coatings were produced on AISI 430 steel by the plasma transfer arc cladding. Three different powder mixtures containing WC (90%, 85% and 80%) and Co (10%, 15% and 20%) were used. Phase composition, microstructural characterization and coating properties were investigated by using scanning electron microscope (SEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD), elemental mapping, hardness and wear test. The wear shape morphology of coatings was determined by SEM. The increased ratio of WC in CoWC powders reduced the degradation of CoWC. The substrate hardness of 180 HV gained a coating hardness value of approximately 462 HV. An increase in the hardness of the coating alloy compared to the substrate was achieved. W2C, WC, CoC and Co6W6C phases were determined on the coating surface. The high levels of WC concentration on the coating surface increased the wear resistance.

Investigation of the microstructure and friction mechanism of novel CoCrCu0.2FeMox high-entropy alloy coating using plasma arc cladding

Investigation of the microstructure and friction mechanism of novel CoCrCu0.2FeMox high-entropy alloy coating using plasma arc cladding

Effects of Cu-Ni-Ti Interlayer on Microstructure and Wear Resistance around Gas Tungsten Arc Cladding Copper Matrix Composite Coatings on Steel

Due to the huge difference in thermophysical properties, it is difficult to obtain a defect-free bonding interface between copper and steel. A Cu-Ni-Ti interlayer was added between a TiC-reinforced copper matrix composite coating and Q235 steel in this study to improve its interfacial bond. The influence of the interlayer on its microstructure and properties was studied by characterizing microstructure, phase composition, and wear resistance of the composite coatings. Both coatings were found to consist of α-Cu matrix, in situ-generated TiC, and Fe-rich phases. With the addition of the Cu-Ni-Ti interlayer, the high-hardness unmixed zone at the interface was successfully eliminated due to the sufficient mixing of the molten pool. Even more importantly, liquid metal embrittlement cracks were also restrained, resulting from the Fe-rich solid solution band that reduced the contact probability around liquid copper atoms with the steel grain boundaries formed. In addition, the results showed that the microhardness of composite coatings was improved and the wear loss reduced by 4.2% after adding that interlayer, which was related to the combined action of solid solution strengthening, second-phase strengthening and grain-refinement strengthening mechanisms.

Recent Advancements in Surface Modification by Gas Tungsten Arc Cladding Technique: A Review

A technique of surface modification used to produce thick coatings with enhanced surface characteristics by developing highly resistive layers on the substrate is known as cladding. It plays a great role to increase the service life of industrial elements. It is broadly applied in chemical, mining, nuclear, power generation, and marine industries. There were a lot of studies done targeting Gas Tungsten Arc Cladding because of its advantages such as user-friendly, low cost, high deposition rate, low dilution, high reliability, etc. The four key features added to the substrate after claddings are dilution of a substrate, microstructure, microhardness, and tribological properties. Considering these features, the current article presents an overview of the Gas Tungsten Arc Cladding technique. The key goal is to reflect on the investigations conducted in the previous decade based on the wear, oxidation, and corrosion performance of cladding surfaces and their key observations. In addition, the effects of Gas Tungsten Arc Cladding process parameters, the substrate-clad materials combination, microstructural improvements, common advantages, and limitations associated with the technique are also presented. New research and industrial people on weld cladding would benefit from the outcomes of this article.

Tribological behaviour of TiB2 ceramic based composite coating deposited on stainless steel AISI 304 by gas tungsten arc (GTA) cladding process

In this study, Titanium (Ti)-Titanium diboride (TiB2) metal matrix composite (MMC) cladding layers were fabricated on an AISI 304 stainless steel substrate by the gas tungsten arc (GTA) cladding process. The composite cladding layer was produced using different powder mixtures: 85 wt% TiB2−15 wt% Ti, 75 wt% TiB2−25 wt% Ti, and 65 wt% TiB2 −35 wt% Ti. During cladding, the GTA process currents were used in the range of 70 A to 90 A with 10 A interval differences and the scan speed in the range of 1.1 mm sec−1 to 1.9 mm s−1 with 0.4 mm s−1 interval differences. All samples were investigated for mechanical properties, microstructure, and phase analysis by Vickers microhardness, scanning electron microscopy (SEM), Energy dispersive x-ray spectroscopy (EDX), and x-ray diffraction (XRD) respectively. The x-ray diffraction (XRD) findings indicate that the composite coatings consist of TiB2, TiB, Ti, Fe3C, B4C, and NiTi phases. The presence of elements B, C, Ti, Cr, Mn, Fe, and Ni in the coating was confirmed by x-ray energy dispersive spectroscopy (EDX). The maximum microhardness value of the composite coating was enhanced in the range of 1639 HV0.1 to 3781 HV0.1, whereas the microhardness of the AISI 304 stainless steel substrate was 194 HV0.1. The average wear rate of the coated samples was determined in the range of 11.09 × 10−9 g N−1-m−1 to 27.63 × 10−9 g N−1m−1, whereas the average wear rate of the AISI 304 steel substrate was 88.414 × 10−9 g N−1m−1. It can be concluded that the maximum micro-hardness of the composite coating increased by 9-19 times than that of the nominal substrate (AISI 304 stainless steel). Also, the wear resistance of the composite coating enhanced by 8 times as compared to AISI 304 steel substrate. It is demonstrated in this study that the processing current, TiB2 content, and scanning speed have significant effect on the microstructure, mechanical, and tribological features of the cladding layers under consideration.

Influence of WC particle content of Fe-based powder-cored wire on microstructure and properties of plasma cladding reinforced layers

The plasma arc cladding process with Fe-based powder-cored wire used to efficiently clad tungsten carbide (WC)-reinforced Fe-based layers on stainless steel is proposed. WC-Fe compound cladding layers on stainless steel were deposited with Fe-based powder-cored wire containing 10%, 20%, 30% or 45% WC particles. Then the macroscopic morphology, microstructure, microhardness and wear performance were characterized in detail. The cladding layers were mainly composed of austenite, but with the increasing WC content, the microstructure of the cladding layers become finer, and α-Fe, Fe3C, Cr7C3, Fe3W3C and residual WC contents gradually rose. The addition of WC can significantly refine the grain size. The low-angle boundary content increased from 14.47% to 71.92%, and the average grain size decreased by 50% from 63.2 to 31.6 µm, which resulted in a significant increase in the hardness and wear resistance of the cladding layers. The average microhardness rose by 38% from 349.0 to 482.1 HV. The wear resistance improved significantly.

Triple-wire plasma arc cladding of Cr-Fe-Ni-Tix high-entropy alloy coatings

High-entropy alloys (HEAs) are promising coating materials for wear resistance applications. However, the preparation of HEA coatings with powder has the disadvantages of high cost and low efficiency. In this study, an innovative triple-wire plasma arc cladding (TW-PAC) method was used to prepare HEA coatings. Nonequiatomic Cr-Fe-Ni-Tix (x is Ti wire feeding speed, x = 0, 0.5, 0.8 and 1.0 m/min, denoted as Ti0, Ti0.5, Ti0.8 and Ti1.0) HEA coatings were successfully prepared by using three commercial wires (ERTi-2, ER304L and Cr20Ni80 wire). With increasing Ti content, the structure of the Cr-Fe-Ni-Tix HEA coatings changed from the single FCC phase to the FCC + γ′ (Ni3Ti) + Laves (Fe2Ti) phase, and the microhardness of the coatings increased from 137 HV to 873 HV. Due to the addition of Ti, Ni3Ti and Fe2Ti phases with high hardness precipitated in the alloy coating, accompanied by the solid solution strengthening effect of the FCC phase, the wear resistance of the coatings was significantly improved (from 9.67 × 10−4 to 1.49 × 10−4 mm3/N·m). The results of this study contribute to the preparation of thick HEA coatings overlarge areas at low cost and with high efficiency and provide new insights into Cr-Fe-Ni-Tix HEA coatings.