WC-Co Coatings Research Articles

Effects of the ambient oxygen concentration on WC-12Co cermet coatings fabricated by laser cladding

Surface coatings of tungsten carbide-cobalt (WC-Co) cermet materials on mechanical components are useful for wear-resistant applications. Laser cladding has recently been widely adopted as a surface modification process offering advantages over other conventional techniques. Thus far, however, the laser cladding of WC-Co cermet coatings has been compromised by the appearance of abundant defects (pores and cracks). In this study we investigated the effect of the ambient oxygen concentration on the laser cladding of WC-Co within an oxygen-control chamber designed for laser cladding. From our results, balancing of a lower oxygen concentration and an optimum heat input was effective in preventing the pores and the decarburization caused by the reaction of carbon and oxygen during the laser cladding.

The Effect of Laser Beam Processing on the Properties of WC-Co Coatings Deposited on Steel.

The main objective of the present work is to determine the effects of laser processing on properties of WC-Co electro-spark deposited (ESD) coatings on steel substrates. Tungsten carbide coatings have been applied to steel substrates using a manual electrode feeder, model EIL-8A. The laser beam processing (LBP) of electro-spark coatings was performed using an Nd:YAG fiber laser. The microstructure and properties of laser treated/melted coatings were evaluated by means of scanning electron microscopy (SEM), X-ray diffraction (XRD), surface geometric structure (SGS) and roughness measurements and adhesion, microhardness, residual stresses, corrosion resistance and application tests. The obtained experimental data were subjected to statistical analysis and multidimensional numerical and visual exploratory techniques. It has been shown conclusively that the laser-treated ESD WC-Co coatings are characterized by lower microhardness, higher resistance to corrosion, increased roughness and better adhesion to the substrate. LBP homogenizes the chemical composition, refines the microstructure and heals microcracks and pores of ESD coatings. The laser treated ESD WC-Co coatings can be used in frictional sliding nodes (e.g., on the front seal rings used in pumps) and as protective layers.

Corrosion Behavior and Galvanic Corrosion Resistance of WC and Cr3C2 Cermet Coatings in Madeira River Water

Thermally sprayed cermet coatings are adequate solutions to improve cavitation and wear resistance of hydraulic turbines made of stainless steel (SS), especially in rivers with a high sediment load, such as the Madeira River in Brazil. However, some cermets are easily dissolved in river water, leading to premature failure of the coating and costly maintenance. Moreover, galvanic corrosion induced by coupling the cermet to a SS can accelerate the coating dissolution. Therefore, the corrosion resistance of six cermets (WC-12Co, WC-10Ni, WC-10Co-4Cr, Cr3C2-25NiCr, Cr3C2-10NiCr and Cr3C2-10Ni) and the galvanic corrosion resistance of these materials coupled to CA6NM SS were evaluated in a solution that simulated Madeira River water. WC-12Co and WC-10Ni cermets exhibited the highest corrosion rates, 0.077 and 0.068 mm/year, respectively, whereas the Cr content in the WC-10Co-4Cr (0.017 mm/year) and Cr3C2-based coatings (0.005 to 0.007 mm/year) led them to corrode at slower rates. Moreover, the WC-10Co-4Cr and Cr3C2-based cermets exhibited negligible galvanic corrosion current when coupled to the CA6NM SS, making them good options to coat hydraulic turbines. In contrast, WC-12Co and WC-10Ni coatings underwent a more severe galvanic corrosion process, which would drastically reduce the lifespan of these materials as hydraulic turbine coatings.

Wear properties of WC–Co and WC–CoCr coatings applied by HVOF technique on different steel substrates

Abstract Low alloy and stainless steel are the most used types of iron-based materials world wide. Their use against in machine element work, reclamation, corrosion and wear resistance are still challenging. To overcome this problem, many steel alloys are coated with cermet coatings to protect the parts from wear and corrosion. In the present study, WC-Co and WC-CoCr coatings were applied by means of a high velocity oxy-fuel (HVOF) technique on AISI 304, AISI 1040, and AISI 4340 steel alloys used as substrates. The aim was to investigate surface properties and wear resistance of the coatings and to determine their relationship with the type of coating and substrate. In accordance with this purpose, hardness and thickness of the coatings were measured, sliding wear tests were performed, scanning electron microscope (SEM) images and X-ray diffractions (XRD) were taken, surface roughness and friction coefficients were determined. The results showed that the WC-CoCr coatings had higher hardness and lower thickness than the WC-Co coatings. Maximum hardness was obtained in the WC-CoCr coating applied to AISI 4340 steel, which was also the hardest alloy among those studied. After wear resistance tests, it was revealed that the wear resistance of the WC-CoCr coatings was better than that of the WC-Co coatings for each steel substrate. During the coating, the new phases resulting from the decomposition of the WC phase in the WC-CoCr coatings contributed more to wear resistance than those of the WC-Co coatings. A lower friction coefficient and lower surface roughness of the WC-CoCr coatings during wear were obtained, resulting in higher wear resistance. A WC-CoCr coating on AISI 4340 alloy which has the highest hardness, lowest surface roughness and lowest friction coefficient resulted in the highest wear resistance among all types studied.

Wear properties of WC–Co and WC–CoCr coatings applied by HVOF technique on different steel substrates

Abstract Low alloy and stainless steel are the most used types of iron-based materials world wide. Their use against in machine element work, reclamation, corrosion and wear resistance are still challenging. To overcome this problem, many steel alloys are coated with cermet coatings to protect the parts from wear and corrosion. In the present study, WC-Co and WC-CoCr coatings were applied by means of a high velocity oxy-fuel (HVOF) technique on AISI 304, AISI 1040, and AISI 4340 steel alloys used as substrates. The aim was to investigate surface properties and wear resistance of the coatings and to determine their relationship with the type of coating and substrate. In accordance with this purpose, hardness and thickness of the coatings were measured, sliding wear tests were performed, scanning electron microscope (SEM) images and X-ray diffractions (XRD) were taken, surface roughness and friction coefficients were determined. The results showed that the WC-CoCr coatings had higher hardness and lower thickness than the WC-Co coatings. Maximum hardness was obtained in the WC-CoCr coating applied to AISI 4340 steel, which was also the hardest alloy among those studied. After wear resistance tests, it was revealed that the wear resistance of the WC-CoCr coatings was better than that of the WC-Co coatings for each steel substrate. During the coating, the new phases resulting from the decomposition of the WC phase in the WC-CoCr coatings contributed more to wear resistance than those of the WC-Co coatings. A lower friction coefficient and lower surface roughness of the WC-CoCr coatings during wear were obtained, resulting in higher wear resistance. A WC-CoCr coating on AISI 4340 alloy which has the highest hardness, lowest surface roughness and lowest friction coefficient resulted in the highest wear resistance among all types studied.

Understanding the Influence of High Velocity Thermal Spray Techniques on the Properties of Different Anti-Wear WC-Based Coatings

This work analyzes the differences found in hard metal coatings produced by two high velocity thermal spray techniques, namely high velocity oxy-fuel (HVOF) and high velocity air-fuel (HVAF). Additionally, the effect of the metallic matrix and ceramic composition and the original carbide grain size on coating properties is compared to the most studied standard reference material sprayed by HVOF, WC-Co. For this evaluation, the physical properties of the coatings, including feedstock characteristics, porosity, thickness, roughness, hardness, and phase composition were investigated. Several characterization methods were used for this purpose: optical microscopy (OM), scanning electronic microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDS), and X-ray Diffraction (XRD), among others. The final performance (abrasive wear and corrosion resistance) shown by the coatings obtained by these two methodologies was also analyzed. Thus, the abrasive wear resistance was analyzed by the rubber-wheel test, while the corrosion resistance was characterized with electrochemical methods. The characterization results obtained clearly showed that the coatings exhibit different microstructures according to feedstock powder characteristics (carbide grain size and/or composition) and the thermal spray process used for its deposition. Thus, the incorporation of WB to the cermet composition led to a high hardness coating, and the complementary hardness and toughness of the WC-Co coatings justify its better abrasion resistance. The presence of Ni on the metal matrix increases the free corrosion potential of the coating to more noble region. However, the WC-Co coatings show a lower corrosion rate and hence a higher protective performance than the rest of the coatings.

Carbide dissolution in WC-17Co thermal spray coatings: Part 1-project concept and as-sprayed coatings

Tungsten carbide-cobalt (WC-Co) thermal spray coatings are widely used for ambient temperature wear applications and are typically deposited using agglomerated feedstock consisting of 1–5 μm sized carbide particles. There are technical challenges to reduce the carbide particle grain size to the desirable <1 μm because of carbide dissolution and carbon loss in-flight’; i.e., in transit from the torch to the substrate. This work explores a novel processing route for the WC-Co system that has been conceptualised previously for the chromium carbide-nickel chromium (Cr3C2-NiCr) system. The approach is based on the tendency for carbides to dissolve in-flight and for precipitation of submicron carbide particles on subsequent heat treatment. Part 1 of this two-part series reviews the equilibrium Co-W-C system to assess this concept for the WC-17 wt%Co composition. WC-17 wt%Co thermal spray coatings, targeting varying degrees of carbide dissolution/decomposition and carbon loss, were sprayed using HVOF, plasma Ar-He and plasma Ar-H2 techniques. The deposits were characterised by XRD pattern fitting, cross-sectional SEM and LECO carbon combustion analysis. The mechanisms of phase formation and carbon loss are discussed.

Scratch Resistance of High Velocity Oxy-Fuel Sprayed WC-20% Co Coatings Reinforced with Carbon Nanotubes

Tungsten Carbide-20 weight % Cobalt (WC-20 wt% Co) coatings were extensively used material to achieve a combination of extreme hardness and excellent strength. Hence, an effort has been made to improve the toughening properties of WC-Co coatings through reinforcement of Carbon Nano-Tubes (CNTs) using High-Velocity Oxy-Fuel (HVOF) spraying process. In this work, 2 wt%, 4 wt%, and 6 wt% of CNTs were blended by the ball milling process with WC-Co powders. These composed powders were deposited by HVOF process on to the plain mild steel substrates. The scratch test analysis on as-sprayed coatings showed that due to the addition of CNTs on WC-Co coatings, the resistance to penetrate the coating surface increased. Also, by varying the percentage of CNTs in the coating system, the pores were reduced. This phenomenon is attributed to the toughening mechanism by forming a CNT bridge which avoids the formation of internal cracks.

Adhesion of HVOF-Sprayed WC-Co Coatings on 316L Substrates Processed by SLM

Different studies have been demonstrated that the surface integrity of substrate bulk materials to be coated has a significant impact on the adhesion of thermally sprayed coatings. It is known that the surface integrity of parts processed by selective laser melting (SLM) differs from those obtained from bulk materials. Although 316L stainless steel is among the most investigated material for SLM, the adhesion of thermally sprayed coatings on 316L stainless steel substrates processed by SLM has not been studied yet. This study aims at evaluating the effect of various mechanical pre-treatments onto 316L stainless steel substrates processed by SLM and their effect on the adhesion of high velocity oxy-fuel (HVOF)-sprayed WC-Co coatings. To differentiate between topographical effects and residual stress-related phenomena, a stress-relief heat treatment of the SLM substrates served as a reference throughout the investigations. The differently pre-treated SLM substrates were investigated with regard to the surface roughness and residual stresses. For the HVOF-sprayed SLM composites, Vickers interfacial indentation tests were conducted to assess the resulting coating adhesion. The findings demonstrated that the HVOF-sprayed WC-Co coatings predominantly exhibit good adhesion to the SLM 316L substrates. However, it was found that the stress state in the SLM 316L substrate surface is more likely to affect the adhesion of the WC-Co coating, while the substrate surface roughness showed a marginal effect.

Room and high temperature wear behaviors of steelmaking slag coating and WC-reinforced composite coatings

Steelmaking slag (SmS) powder and commercial WC-reinforced composite powders (NiCrBSi/WC (50/50) and WC/Co (88/12)) were deposited on the AISI 316 L stainless steel substrates by atmospheric plasma spraying (APS), and high velocity oxy fuel (HVOF) spraying techniques. The microstructures as well as the room and high temperature wear performances of the fabricated coatings were comparatively evaluated to assess the usability of steelmaking slag, an industrial by-product of steelmaking industry, as an alternative protective coating material against room and high temperature sliding wear. The friction-wear tests of all coatings against Al2O3 abrader were performed on a high-temperature ball-on-disk tribometer at room temperature and elevated temperatures (250 °C–500 °C) under 5 and 10 N normal loads. The powders, as-sprayed and worn samples were characterized by X-ray diffraction (XRD), scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) techniques and a 3D optical surface profiler. The SmS coating structure displayed the highest porosity which was followed by NiCrBSİ-WC and WC-Co coatings. WC-Co coating exhibited the lowest specific wear rates until being damaged at 500 °C due to severe decarburization. NiCrBSi-WC and SmS coatings withstood the 500 °C wear test and NiCrBSi-WC coating slightly outperformed SmS coating under high load whereas SmS coating displayed lower wear rates under low load. SmS coating's stable oxide-rich structure acted in the favor of the coating's wear performance. The slight increase in the wear rate of SmS coating with the increase of temperature from 250 °C to 500 °C is believed to be induced by the large temperature gradients between the real contact areas and their surroundings. Overall, plasma sprayed SmS coating exhibited promising results when compared with its commercial HVOF sprayed WC-reinforced composite counterparts.

Wear and microstructural properties of coatings on Weldox 700 steel

Abstract In this study, the wear and microstructure properties of some coatings produced on Weldox 700 steel were investigated via a high-velocity oxygen fuel (HVOF) technique. For the coating types, NiCrBSi, WCCo and CoNiCrAlY-based coatings were selected. Microstructure and phase formation were examined via scanning electron microscopy (SEM), X-ray diffraction and X-ray energy dispersive spectrometry. Wear tests of the substrate and coatings were made using the ball-on-disc method. It can be seen from the SEM images that the coating layers are metallurgically/ mechanically connected to the substrate and have a mostly homogeneous structure. The hardness measurement was taken from the top of the coatings. The hardness values of the coatings were significantly higher than those of the substrate. The coated substrates exhibit a very good tribological performance compared with the substrate. Depending on the load, the wear rate and coefficient of friction of the coatings were much lower as compared with the Weldox 700 steel substrate.

Fabrication, Wear, and Corrosion Resistance of HVOF Sprayed WC-12Co on ZE41 Magnesium Alloy

This study shows that WC-12Co coatings with low porosity and high wear and corrosion resistance can be applied by high velocity oxygen-fuel (HVOF) on a low melting and highly flammable ZE41 magnesium alloy. This provides a novel and promising use of the high-energy thermal spraying technique on low temperature melting substrates. The spraying distance used was 300 mm, which is between two and three times the recommended distanced for HVOF coating with WC-12Co on steels. Despite this, the WC-12Co coatings obtained were homogeneous, crack-free, and dense. The coatings were very well adhered to the substrates and the spraying distance allowed avoiding any thermal affectation of the substrate. The thickness of the coatings was limited to 45 μm to avoid a big mass increase in the samples. The effect of the number of layers, the O2/H2 ratio and the gas transport flow in the coating was studied. The coatings reduced the wear rate of the substrate by 104 times, making them wear resistant. Electrochemical corrosion tests were conducted to study the corrosion protection of the coatings, showing that it is possible to protect the magnesium substrate for 96 h in contact with 3.5 wt.% NaCl aqueous solution.

Tribological investigation of surface structures processed by high-feed milling on HVOF sprayed WC-12Co coatings

Since properties of high-velocity oxy-fuel (HVOF) sprayed WC-12Co coatings are limited due to the inherent restrictions of the material, new approaches that involve tailored surfaces and designing friction properties of functional materials have attracted enormous interest. Within this scope, two different deterministic patterns are machined on as-sprayed and polished WC-12Co coatings by means of a high-feed milling (HFM) process, whereby different process parameters with respect to the feed per tooth as well as the lead angle are taken into account. The produced high-feed milled surfaces are investigated with respect to the resulting topography and tribological properties under dry sliding conditions.The tribological examination of the high-feed milled surfaces reveals a decreased coefficient of friction (COF) compared to the polished WC-12Co coating sliding against a 100Cr6 counter-body. The lower friction is attributed to the reduction of the contact area as well as the capability of the cavities to store the transferred material resulting from wear debris. With respect to the different surface patterns, higher values for the kurtosis Sku lead to a reduction of friction. In contrast to the results presented for 100Cr6, the WC-12Co surfaces sliding against Al2O3 counter-bodies exhibit an almost constant COF for all surfaces. Although the reduced contact area leads to increased tribological stresses, the processed surfaces show a high resistance to sliding wear. Finally, it is clarified that time- and cost-consuming mechanical surface treatments such as polishing or grinding prior to a subsequent HFM process do not have to be applied. Therefore, HFM enables a new manufacturing route to structure WC-12Co coatings as well as to modify the tribological properties.

Microstructures and high-temperature self-lubricating wear-resistance mechanisms of graphene-modified WC-12Co coatings

To reduce the friction coefficient of cobalt-cemented tungsten carbide (WC-12Co) wear-resistant coatings, graphene was compounded into WC-12Co powder via wet ball milling and spray granulation. Self-lubricating and wear-resistant graphene coatings were prepared via detonation gun spraying. The presence, morphologies, and phase compositions of graphene in the powders and coatings that are obtained through different powder preparation processes were analyzed. The analysis was performed using the following technologies: energy-dispersive X-ray-spectroscopy (EDXS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy. The mechanical properties of the coatings were studied using a microhardness tester and a universal drawing machine. The friction and wear properties of the coatings were studied using an SRV-4 friction and wear tester. The results showed that the graphene content in the WC-12Co coating modified with graphene was higher than that without modification; graphene was embedded in the structure in a transparent and thin-layer state. The adhesive strength of this coating at approximately 25 °C was approximately 60.33 MPa, and the hardness was approximately 984 HV0.3. After high-temperature treatment, the adhesive strength and hardness of the graphene oxide (GO)/WC-12Co coating decreased slightly (the lowest adhesive strength of 53.16 MPa was observed after treatment at 400 °C, and the lowest hardness of approximately 837 HV0.3 was observed after treatment at 300 °C). Compared to the friction coefficient (0.6) of the WC-12Co coating obtained at room temperature, the friction coefficient of the GO/WC-12Co coating was decreased by approximately 50% of that value. The graphene-modified coating was continuously exposed to the wear tracks on the surface of the contacting materials during friction, and a lubricating film was formed in the microareas in which the wear tracks were present. The coating exhibited improved self-lubricating and wear-resistant effects compared to the unmodified WC-12Co coating. The results of this study demonstrated that graphene could be effective in self-lubrication and wear-reduction in a temperature range of 100–200 °C, as a friction coefficient of 0.3 was maintained.

Fabrication of mechanically durable slippery surface on HVOF sprayed WC-Co coating

The limitations of the existing art and the fragility of the developed hydrophobic surfaces limit its applications to the real field. Hence, the fabrication of slippery surface with the required durability has been considered to be an important academic and industrial challenge. The WC-Co coating possesses exceptional mechanical and tribological properties and is considered as one of the most durable surfaces available. The WC-Co coating with nanoscale surface roughness is in high demand in aerospace and automobile industries. In this study, shape adaptive grinding (SAG) is conducted to attain nanoscale surface roughness on hard WC-Co coatings. The static and dynamic wetting behaviour of as-sprayed, ground and nanofinished WC-Co coating are studied by analysing the static contact angle, sliding angle, and contact angle hysteresis (CAH). A model is proposed to predict the apparent contact angle of the coatings. The nanofinished coating exhibits a lower sliding angle and contact angle hysteresis and the water droplets get completely released from the surface in dynamic condition. This is attributed to the lower surface retention force and the presence of trapped air inside the porosities and the nano-well of the coating surface. The durability test of the nanofinished surface is also performed by abrasion test and sand impact test and it is observed that the surface can retain its original topographical features and wetting properties. This report presents a sustainable method for the fabrication of a mechanically durable slippery surface.

Improvement of microstructural and tribological properties of APS carbide coatings via PTA surface melting

ABSTRACTIn the current study, WC-Co and Cr3C2-NiCr coatings deposited on 90MnCrV8 steel surface via an atmospheric plasma spray (APS) system were modified by the plasma transferred arc (PTA) welding method. Microstructural defects including micro-cracks, voids, pores, and non-uniform zones were determined in the APS deposited layers. The microstructural defects were terminated by the PTA melting process due to the dissolving pool at high temperature. Strong metallurgical bonding between the coating layer and substrate and columnar dendrites and inter-dendritic precipitates were observed during the PTA melting process. Following the PTA melting process, MC, M3C, and M7C3 hard phases were formed in the coating layers. The hardness and wear performance of the coating layers significantly increased due to the PTA surface modification. The main reason for the significant increases in wear performance corresponded to the newly formed hard carbide phases and elimination of microstructural defects via the PTA surface modification.

Wear and microstructural properties of coatings on Weldox 700 steel

Abstract In this study, the wear and microstructure properties of some coatings produced on Weldox 700 steel were investigated via a high-velocity oxygen fuel (HVOF) technique. For the coating types, NiCrBSi, WCCo and CoNiCrAlY-based coatings were selected. Microstructure and phase formation were examined via scanning electron microscopy (SEM), X-ray diffraction and X-ray energy dispersive spectrometry. Wear tests of the substrate and coatings were made using the ball-on-disc method. It can be seen from the SEM images that the coating layers are metallurgically/ mechanically connected to the substrate and have a mostly homogeneous structure. The hardness measurement was taken from the top of the coatings. The hardness values of the coatings were significantly higher than those of the substrate. The coated substrates exhibit a very good tribological performance compared with the substrate. Depending on the load, the wear rate and coefficient of friction of the coatings were much lower as compared with the Weldox 700 steel substrate.

Effects of cyclic heating and water-cooling on the mechanical properties of WC-Co coatings

To determine the effect of heating and water-cooling on the mechanical properties of the WC-Co coatings, we conducted a series of mechanical tests on the HVOF (high-velocity oxygen-fuel) sprayed WC-Co samples. These coatings were first heated to the target temperatures (200–800 °C), followed by rapid cooling with water. Mechanical properties were tested after thermal treatments. Microstructural changes were also observed using a scanning electron microscope and optical microscope. According to experimental results, the microhardness, residual stress and adhesive strength of the heated WC-Co coating changed significantly after water-cooling. As heating temperature rises, changes in these properties become more pronounced. However, the number of cycles has less effect on the mechanical properties of the coatings and the effect mainly occurs in the first 30 cycles. Compared with the argon-cooling method, water-cooling induces greater changes in the mechanical properties at higher target temperatures. This indicates that water-cooling can damage the heated WC-Co coatings more remarkably than the other cooling treatment. Nevertheless, after about 30 cycles, changes in mechanical become less pronounced. Additionally, cobalt content has little impact on the mechanical properties of the coating after heating and water-cooling.

Self-lubrication and wear-resistance mechanism of graphene-modified coatings

To reduce the friction coefficient of WC-17Co wear-resistant coatings, Graphene oxide were used to mix with WC-17Co powder. The SEM, EDS and Raman results were used to analyze the morphology and phase composition of graphene oxide in the powder and coating obtained by plasma spraying processes. The mechanical properties of the coatings were studied by using a microhardness tester and a universal testing machine. The friction and wear properties of the coatings were studied by using a UMT-2 friction and wear tester. The results show that among the pulverization processes, the spray granulation process can achieve a stronger and more uniform adhesion of graphene oxide on the surface of WC-17Co particles, and the graphene oxide content in the coating is higher. Graphene is still embedded in the coating as transparent, thin sheets. The bonding strength is approximately 63 MPa, the hardness is approximately 931 HV0.1, and the friction coefficient of the graphene oxide coating is reduced by approximately 22% compared to that of the coating without graphene. The formation of lubrication films in the micro-area improves the self-lubrication and antiwear effects.

Evaluation of the mechanical properties of WC-Ni composite coating on an AISI 321 steel substrate

In this study, The WC-Ni composite powders were fabricated by the electroless plating of nickel-phosphorus, followed by the appliance of the obtained particles as a coating on an AISI 321 steel by laser cladding method. Effects of main laser parameters, including power, scanning speed, and powder feed rate on the geometric properties were reviewed. The optimum single-pass specimen was chosen after considering the geometrical shape, dilution, and crack and porosity amount of the single-pass specimens. It was found that the increase in laser power and powder feed rate results in the rise of the height and the width of the coatings. In contrast, coatings with lower height and width were achieved by employing lower laser power and powder feed rates. The procedure was followed by the laser cladding of the WC-Ni powders on 321 steel substrate under the optimum coating parameters with a variety of overlap amounts; 30, 50, and 70 percent. By investigating the formed phases and microstructure of the overlap specimens, the 70 percent overlap coating was chosen as the optimal one. Mechanical and wear tests were conducted on the optimal overlap specimen. Experiments indicated that the hardness, elasticity modulus, and fracture toughness of the coating were, respectively, 1457 Vickers, 6.24 Mpa.m1/2, and 250 GPa. The micro-hardness of the WC-Ni coating was 1.2–1.6 times higher than the WC-Ni, WC-Co and WC-Co-Ni coatings, made by thermal spray coating. Also, the toughness of the coating was 1.5 times higher than the WC-Co thermal sprayed coat. The elasticity modulus of the WC-Ni coating (250 GPa) was 1.1 times more than the WC-Co coating manufactured with the laser cladding method.