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Purpose This paper aims to investigate the fretting wear mechanism of an Al-Li alloy at room temperature, the tangential fretting wear tests were carried out. Design/methodology/approach The effects of displacement amplitude and fretting frequency on the tangential fretting wear characteristics were mainly investigated. The experimental data obtained are analyzed and compared. Findings The results indicated that the fretting friction coefficient increased with the increase of displacement amplitude. As the displacement amplitude increased, the wear scar morphology changed significantly, mainly in terms of delamination debris and furrow scratches. The wear mechanism changed from initial mild wear to more severe oxidative wear, adhesive wear and abrasive wear. Originality/value This paper extends the knowledge into mechanical tight connections. The conclusions can provide theoretical guidance for the fretting of mechanical tight connections in the field of automotive lightweight and aerospace. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2019-0490/

TiO2 nanotube coatings with different structures were prepared on bone plate surface by anodic oxidation at different voltages or time and in an ethylene glycol solution containing 0.3 wt% ammonium fluoride (NH4F) and 2 vol% deionized water. Subsequently, the morphology, elemental composition, crystalline structure, surface roughness, microhardness, contact angle, adhesion force, corrosion resistance and wear resistance of the as-prepared coatings were characterized. At the optimized oxidation voltage of 60 V in microstructural, biocompatibility and properties of coatings considerations, the prolonged oxidation within a certain range led to increasing nanotube thickness and inner diameter, which further improved the properties of TiO2 nanotube coating samples. Specifically, surface roughness and adhesion force of the coatings increased progressively, the maximum adhesion force was (12.10 ± 0.50) N, while their contact angle and microhardness decreased gradually. Moreover, the coatings also exhibited the enhanced corrosion resistance in simulated body fluid (SBF), with the corrosion potential or the corrosion current increased by 56.91% or decreased by 79.45% to the largest extent. During dry friction, both friction coefficient and wear groove depth declined, corresponding reduction rates up to 22.52% and 49.01% evidenced the improved wear resistance. Besides, the major wear mechanism of the coating was a combination of abrasive and adhesive wear. Accordingly, the voltage of oxidation at 60 V and the oxidation time of 6 h were determined as the optimum processing parameters for preparing TiO2 nanotube coating on the bone plate surface, and the nanotube inner diameter and coating thickness were (118 ± 3.5) nm and (34 ± 2.8) μm, respectively. The novelties of the present study are: 1. A uniform and neat TiO2 nanotube coatings were fabricated using the anodic oxidation method. The effects of oxidation voltage and oxidation time on the microstructure of TiO2 nanotube array were further examined, and the relationship between oxidation parameters and coating morphology was concluded. On that basis, the changes in the structural parameters of TiO2 nanotube coatings under other oxidation parameters can be inferred. 2. The morphology, elemental composition, crystalline structure, surface roughness, microhardness, contact angle, adhesion force, corrosion resistance and wear resistance of TiO2 nanotube coatings were systematically studied, and the relationship between roughness and hydrophilicity of the coatings was discussed. 3. The wear process of anodized TiO2 nanotube coatings under dry friction conditions was explained according to the friction coefficient curves, and the wear mechanism of the coating was clarified based on the wear morphology and the energy spectrum analysis of the coatings. 4. The optimum oxidation voltage and oxidation time for preparing of TiO2 nanotube coating on the bone plate surface by anodization were determined as 60 V and 6 h, respectively, when the electrolyte was an ethylene glycol solution containing 0.3 wt% NH4F and 2 vol% deionized water.

This paper presents a new method of postweld treatment. The 5154 aluminum alloy was cleaned by Nd:YAG laser after welding. The surface morphology, energy spectrum, friction and wear properties, hardness, and residual stress of the welded joint at different cleaning speeds were studied. The results show that an Nd:YAG laser can effectively remove the welding slag and eliminate the pores in the weld under a certain cleaning speed. When the cleaning speed is in the range of 5.2–20.7 mm/s, laser cleaning can improve the heat-affected zone’s tribological characteristics. Laser cleaning can eliminate the residual stress of the welded joint and improve the welding joint’s strength, which provides a reference for laser cleaning instead of traditional heat treatment.

H13 die steel often fails as a result of physical and chemical effects such as wear, erosion and cyclic stress. Accordingly, the study evaluates Co-based gradient coating on an H13 steel featuring a stress-relieving effect. Scanning electron microscope and X-ray diffraction were used to analyze the microstructure and phase of the coatings. A microhardness tester and friction and wear tester were used to compare the hardness and wear resistance of the coatings and the substrate, and the wear morphology was observed. A pendulum impact test was used to compare the impact resistance of the coatings and the substrate, and the fracture morphology was observed. Finally, a corrosion test was used to compare the corrosion resistance of coatings and substrate. The results show that the Co-based gradient coatings have good combinations with the substrate, the hard phase content gradually increases from the bottom to the top of the coating, and the crystal microstructure generally maintains a distribution trend from coarse to fine. The hardness of the gradient coatings is significantly higher than the substrate, and from the coating surface to the substrate, the hardness decreases slowly. The wear loss of the coatings is much lower than that of the substrate, the main wear mechanism of the substrate is abrasive wear, and the main wear mechanism of the coatings is brittle spalling. While the gradient coatings increase the surface hardness, the brittleness also increases, the impact resistance of the coatings is lower than that of the substrate, the fracture form of the substrate is a ductile fracture, and the fracture form of the coating is a brittle fracture. The gradient coatings effectively improve the corrosion resistance of the substrate surface, and the higher the content of the reinforcing phase, the better the corrosion resistance of the coatings.

The roles of calcium oxide on fluorapatite crystal morphology, crystallization kinetics behavior and mechanical property of functional glass-ceramics in the SiO 2 -Al 2 O 3 -K 2 O-CaO-P 2 O 5 system were investigated. Glass compositions with calcium oxide content (in wt%) of (1) 3.8, (2) 4.2, (3) 5.3, (4) 6.0, and (5) 6.9 were fabricated by sintering method. Different heat treatments were carried out at the temperature of 930 °C for 30 min, 1100 °C for 30 min and 1100 °C for 120 min, respectively. The results showed that the length of fluorapatite crystal increased with temperature and heating time, however, the length increased firstly and then decreased dramatically with the increase of calcium oxide content. Meanwhile, the minor crystalline phase changed from low albite to anorthite. The microhardness was also influenced by different crystal morphologies. The results revealed that it was possible to control crystalline phase and mechanical property of fluorapatite glass-ceramics by changing calcium oxide content and heat treatment regime.

In this paper, the effect of hydrogen on true and pseudo twinning of γ phase in a TiAl based alloy was investigated by means of plane strain compression tests at elevated temperature. The results showed that hydrogen could increase true- and pseudo-twin boundaries of γ phase. Hydrogen-decreased stacking fault energy, hydrogen-promoted Shockley dislocation movement, hydrogen-decreased stacking fault energy and hydrogen-enhanced element diffusion promoted γ-phase mechanical twinning and grain boundary migration. Furthermore, more γ-phase mechanical twinning and grain boundary migration led to more true-twin boundaries. Additionally, hydrogen could promote order twinning. The interaction between true- and order-twin boundaries cloud result in pseudo-twin boundaries. Therefore, hydrogen-promoted true and order twinning could indirectly increase pseudo twinning.

The atomic-scale investigation on fretting wear mechanism of γ phase in a cast Ti-45Al alloy was conducted. The fretting wear of the alloy at 25 °C was a mixture of abrasive and adhesive wear. The results showed that serrated waves were observed in the force-time curves, which was associated with the local welding between the abrasive particles and substrates when fretting wear occurred. The main plastic deformation mechanism was mechanical twinning in the substrates. The introduction of order-twin (RT) interfaces restricted the downward movement of abrasive particles. The twinning across lamellae was dominant in the substrates with a RT lamella. Dislocation pile-ups in RT interfaces induced the formation of twin embryo. The successive dislocation dissociation 1 / 6 [ - 12 - 1 ] → 1 / 6 [ 011 ] + 1 / 6 [ - 11 - 2 ] was the nucleation mechanism of twinning across lamellae.

CuZrAlTiNi High entropy alloy (HEA) coating was synthesized on T10 substrate using mechanical alloying (MA) and vacuum hot pressing sintering (VHPS) technique. The MA results show that the final product of as-milled powders is amorphous phase. The obtained coating sintered at 950 °C is compact and about 0.9 mm in thickness. It is composed of a couple of face-centered cubic (FCC), one body-centered cubic (BCC) solid solutions and AlNi 2 Zr phase. The interface strength between coating and substrate is 355.5 MPa measured by three point bending test. Compared with T10 substrate, the corrosion resistance of CuZrAlTiNi HEA coating is enhanced greatly in the seawater solution, which is indicated by the higher corrosion potential, wider passivation region, and secondary passivation. The average microhardness of the coating reaches 943 HV 0.2 , and is about 3.5 times higher than the substrate, which is mainly ascribed to the uniformly dispersed nano-size precipitates, phase boundary strengthening and solid solution strengthening. Moreover, the wear resistance of the coating is slightly improved in comparison with the substrate.

The surface of the aluminum alloy is prone to oxidation, which in turn affects the quality of the weld. The 5A12 aluminum alloy was cleaned by acousto-optic Q-switched diode-pumped Nd:YAG laser and the effects of different laser powers and different cleaning speeds on the surface roughness, microstructure, element content, microhardness, residual stress and corrosion resistance of aluminum alloy were investigated. The results show that when the power is 98W and the cleaning speed is 4.1 mm/s, the effect of Nd: YAG laser on the removal of oxide film on 5A12 aluminum alloy surface is the most effective. After laser cleaning, the smoothness and strength of aluminum alloy surface can be effectively improved. However, as a major element in 5A12 aluminum alloy, the content of magnesium decreased. At the same time, the residual tensile stress was generated on the surface of the aluminum alloy after cleaning, and the corrosion resistance slightly decreased.

According to research, we have learned that zinc has excellent cathodic protection performance, that the corrosion products of aluminum and magnesium can form dense and stable passivation films to protect internal materials of coatings, and that TiO2 has excellent photocatalytic self-cleaning performance which will form a physical adsorption film on the surface to isolate the external corrosion solution. In this paper, a Zn-Al-Mg-TiO2 pseudo alloy coating was prepared by cold spray technique on a Q235 substrate. The protective performance of Zn-Al-Mg-TiO2 for marine metal equipment was studied using dynamic salt water corrosion testing, electrochemical testing, and friction and wear testing. The microstructure, composition, and wear marks of coatings were observed using a scanning electron microscope (SEM), energy dispersive spectrometer (EDS), and white-light interferometer. The results show that the Zn-Al-Mg-TiO2 coating has excellent corrosion and wear resistance, which can provide long-term and stable protection for the substrate.

In order to slow down the corrosion and wear of offshore equipment, the Zn&ndash, Al composite coating was prepared on Q345 substrate by cold spray technique. The mass fraction of Zn and Al in the raw material was 2:3. The microstructure of the original coating was observed by scanning electron microscopy (SEM) and was characterized by energy dispersive spectrometer (EDS). From the composite alloy coating obtained by cold spraying, it was observed that the Zn and Al particles were uniformly distributed without oxidation product, and the powder particles were significantly plastically deformed. The microstructure of the composite coating is very dense and has strong adhesion to the substrate. Neutral salt spray test (NSS) and electrochemical accelerated corrosion test results showed that Zn&ndash, Al composite coating can effectively provide corrosion protection.

FeCoNiTiAlx (x = 0, 0.5, 1) high-entropy alloy coatings were prepared by laser cladding technology. The phase, microstructure, hardness, wear resistance and corrosion resistance were tested and analyzed. The results showed Al element promoted the conversion from the FCC phase to the BCC phase. The coating presented dendritic structure due to the addition of the Al element, while the number of dendrites increased. And the average hardness of the coating increased from 204 to 623 HV. The addition of the Al element increases the corrosion current density of the coating from 1.270 &times, 10&minus, 5 to 3.489 &times, 5 A/cm2. The wear rate of the coatings decreases with the increase of Al content according to dry friction and wear, which indicates the wear resistance of the coating was improved by adding the Al element. According to the corrosion wear test in 3.5% NaCl solution, it can be found that the wear rate of the coating increases firstly and then decreases with the addition of the Al element, which indicates that the addition of the Al element intensifies the wear of the coating in 3.5% NaCl solution.

Improving the property of coating is the focus of current marine protection research. In this paper, the Zn-Al-Mg-TiO2 and Zn Al coatings were prepared by cold spraying. The wear, electrochemical experiment and methyl blue degradation tests were carried out to study the tribological, anticorrosive and antifouling properties of coatings. The microstructure, composition, and wear scar of coatings were analyzed by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), and white-light interferometer. The results showed that the wear mechanism of the Zn-Al-Mg-TiO2 coating was mainly abrasive wear, and the wear property of the Zn-Al-Mg-TiO2 coating was better than Zn Al coating. Compared with the Zn Al coating, Zn-Al-Mg-TiO2 coating had lower corrosion current density. In addition, the Zn-Al-Mg-TiO2 coating can rapidly degrade methyl blue in a UV-rich environment, but Zn Al coating did not.

To investigate the effect of hydrogen on the high-temperature deformation behaviors of TiAl-based alloys, the high-temperature tensile experiment was carried out on a Ti&ndash, 45Al&ndash, 9Nb (at.%) alloy with the H content of 0 and 0.8 at.%, respectively. Then, the effect of hydrogen on the high-temperature mechanical properties of the as-cast alloy was studied, the constitutive relations among stress, temperature, and strain rate were established, and the microstructure was analyzed. The results indicated that, compared with the unhydrogenated alloy, the flow stress of the hydrogenated alloy was significantly reduced, and the peak stress of the hydrogenated alloy decreased by (16.28 &plusmn, 0.17)% deformed at 1150 &deg, C/0.0004 s&minus, 1. Due to the presence of hydride (TiAl)Hx in the alloy, the elongation showed a decline trend with increasing strain rate at the same deformation temperature. Compared with the unhydrogenated alloy, the elongation of the hydrogenated alloy reduced by (26.05 &plusmn, 0.45)% (0.0004 s&minus, 1), (23.49 &plusmn, 0.38)% (0.001 s&minus, 1), and (14.23 &plusmn, 0.19)% (0.0025 s&minus, 1), respectively, indicating that 0.8 at.% H softened the Ti&ndash, 9Nb alloy and reduced the high-temperature plastic deformability. Under the same deformation condition, the deformation extent of the hydrogenated alloy was less than that of the unhydrogenated alloy. There were more residual lamellae in the hydrogenated alloy, and the extent of dynamic recrystallization was lower than that of the unhydrogenated alloy.

Comparative study on sliding friction and wear properties of low alloy wear-resistant steel Hardox400 and NM400 at room temperature using Retc multi-function friction and wear tester. The hardness, microstructure and wear surface morphology of the test steel were compared and analyzed by microhardness tester, optical microscope (OM) and scanning electron microscope (SEM). The results show that the wear mechanism of the two kinds of test steels is mainly manifested as abrasive wear and fatigue wear. The Martensite-Bainite Dual Phase Structure in Hardox400 has a good match of strength and toughness, and the sliding wear performance is better than the NM400 of martensite structure.

The CoCrFeNi high-entropy alloy coatings (HEACs) with different weight ratios (10 and 30 wt.%) of WC additions have been prepared using mechanical alloying and a vacuum hot pressing sintering technique on a Q235 steel substrate. The microstructures, microhardness, wear resistance, and corrosion resistance of HEACs were studied. The CoCrFeNi(WC) powders were obtained by mixing the CoCrFeNi HEA powders and WC particles. The sintered products of both HEACs with high relative density contained one solid solution phase with face-centered cubic structure, WC, and unknown precipitate phases. The transition boundary had a good metallurgical bonding with the coating and substrate. The average microhardness values of CoCrFeNi HEACs with 10 and 30 wt.% WC additions reached 475 and 531 HV respectively, which were far higher than that of the substrate (160 HV). Moreover, both coatings exhibited better wear resistance than the substrate under the same wear conditions. The 30 wt.% WC HEAC displayed the lower friction coefficient, and the shallower wear groove depth. The grain refinement strengthening and second-phase particle strengthening could be beneficial to the enhanced hardness and wear resistance of coatings with WC additions. The corrosion behavior of the tested samples in the 3.5 wt.% NaCl solution were investigated using electrochemical polarization measurements. The CoCrFeNi(WC) coatings all revealed the improved corrosion resistance. Especially, a 10 wt.% WC addition remarkably enhanced the comprehensive corrosion resistance and easy passivation of CoCrFeNi HEAC.

As a veneering porcelain coating of dental prosthesis, two-body and three-body wear behavior of dental glass-ceramic with the main crystalline phase of fluorapatite has not been comprehensively studied. In this work, a self-made fluorapatite glass-ceramic was synthesized and the mechanical and tribological performances of the glass-ceramic were tested, comparing with a commercial feldspathic glass-ceramic. The friction and wear experiments were performed between disk-shaped glass-ceramics and natural teeth in two-body (dry, water, saliva) and three-body (slurry) modes, respectively. Results showed that good mechanical properties of fluorapatite glass-ceramic can be achieved by the sintering process. In both two-body and three-body modes, the fluorapatite glass-ceramic had a smaller friction coefficient and wear rate and caused less damage on antagonistic teeth than the feldspathic glass-ceramic. The greater mechanical properties give fluorapatite glass-ceramic a better wear resistance and reduce the adhesive wear.

TiO2 nanotubes have a good application prospect in the field of drug load and delivery. In this study, TiO2 nanotubes were prepared by electrochemical anodic oxidation with voltage and time of 60 V and 2 hours, respectively. After anodization, it was annealed at 450 ° C for 2 hours. The crystalline phases as well as the morphology and structure of nanotubes were characterized by XRD, field-emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDS), respectively. The results show that surface of TiO2 nanotubes are clean and highly ordered construction. In addition, the diameter and wall thickness of the nanotubes are about 110 nm and 5 μm, respectively. Finally, the TiO2 nanotubes which load iodine by electrodeposition method have polymer particulate iodine on the surface, thereby developed a kind of orthopaedic implants with antibacterial properties, which is expected to be widely used in clinical practice.

There are many researches on the deformation behavior of wrought magnesium alloys, such as AZ31, AZ80, AZ91, and ZK60 magnesium alloys at different temperatures and strain rates, but few of them focuses on the deformation behavior of AZ41M and ZK60M alloys, especially under the twin-roll casting (TRC) state. Meanwhile, the existing researches only focus on the grain refinement law of the magnesium alloys under deformation conditions, the deformation mechanism has not been revealed yet. The hot compression behavior of AZ41M and ZK60M magnesium alloys under the temperature and strain rate ranges of 250–400 °C and 0.001–1 s−1 are studied by thermal simulation methods using Gleeble 1500 machine and virtual simulation using finite element analysis software. Simulation results show that sine hyperbolic law is the most suitable flow stress model for wider deformation conditions. The most reasonable selected deformation conditions of ZK60M alloy is 350 °C/0.1 s−1 for TRC and 350 °C/1 s−1 for conventional casting (CC), while AZ41M alloy is 300 °C/0.01 s−1 for TRC and 350 °C/0.1 s−1 for CC. Deformation behavior and dynamic recrystallization (DRX) mechanism of them are analyzed at the same deformation conditions. The microstructures of AZ41M and ZK60M alloys are observed at different deformed conditions by optical microscopy (OM) and electron back scatter diffraction (EBSD) and it reveals the flow behavior and deformation mechanism of them. Working harden and work soften contribute to the activation of basal, non-basal slip systems which promote DRX. The proposed research reveals the deformation behavior and mechanism of the AZ41M and ZK 60M magnesium alloys and concludes their optimized deformation parameters and processes and provides a theory basis for their manufacturing and application.

The microstructural features of hypoeutectic Al-10%Si alloy were observed using optical microscopy and electron backscatter diffraction. The results show that primary silicon particles are frequently found in hypoeutectic alloys. Hence, the nucleation and growth mechanisms of the precipitation of primary silicon of hypoeutectic Al-10%Si alloy melts were investigated. It was discovered that Si atoms are easy to segregate and form Si-Si clusters, which results in the formation of primary silicon even in eutectic or hypoeutectic Al-Si alloys. In addition, solute redistribution caused by chemical driving force and large pile-ups or micro-segregation of the solute play an important role in the formation of the primary silicon, and the solute redistribution equations were derived from Jackson-Chalmers equations. Once Si solute concentration exceeds eutectic composition, primary silicon precipitates are formed at the front of solid/liquid interface.

Al 67 Ti 25 Cr 8 powders with cubic L1 2 ordered structural characteristic are formed by mechanical alloying and annealing process. X % Al–Al 67 Ti 25 Cr 8 composites ( X = 5, 10, 15, 20 wt.%) were fabricated by hot isostatic pressing. Porosity of bulk specimen, first decreases, and then increases with increasing Al content at same test conditions. The 10 wt.% Al–Al 67 Ti 25 Cr 8 composite exhibited good compactibility, whilst the 20 wt.% Al–Al 67 Ti 25 Cr 8 composite exhibited honeycomb-shaped structures due to the expanding and shrinkage of Al. Owing to Al additions jamming the micro-pores and micro-cracks, Al–Al 67 Ti 25 Cr 8 composites with suitable Al contents (10–15 wt.%) exhibit improved strength (0.2%YS as 420 MPa and UTS as 469 MPa) and fracture toughness (10.4 MPa m 0.5 ). However, too high Al additions caused the deterioration of mechanical properties.

Effects of yttrium (Y) on the microstructure and properties of as-cast Mg-Al-Zn (AZ91) alloys were studied. Y additions not only change the microstructure but also influence the mechanical properties of AZ91 alloy. AZ91 unmodified alloys under as-cast state indicate that eutectic phase Mg17Al12 is continuous and reticulated. Yttrium addition to AZ91 casting alloys has an important influence on the primary-phase and precipitation. When the Y content is 0.3 wt.%, no Y-containing compound was observed. When the Y content is 0.6 and 0.9 wt.%, Al2Y phase formed in the alloy and the growth morphology of eutectic Mg17Al12 phase is modified. When the Y content is further increased to 1.2 wt.%, the Al2Y phase becomes coarser and Mg17Al12 transforms into a cotton-shape structure. The results showed that Y can improve significantly as-cast microstructure of AZ91 alloys, refining Mg17Al12 phase and increasing in hardness and strength and decreasing in impact toughness and elongation.

The spherical plain bearing was established using the UG of three-dimensional modeling software and imports model into the finite element software ANSYS-Workbench in modal analysis. Under two different materials between GCr15 and Ti44Al2Cr8Nb3V0.5B0.5Al2O3(referred TiAl based alloys), analysis of modal frequencies and mode shapes for spherical plain bearings. The result shows that the deformation of TiAl base alloys spherical plain bearings is significantly less than the amount of deformation of GCr15 spherical plain bearings. So spherical plain bearings modal analysis provide a theoretical basis and reference in the spherical plain bearing applications for the new TiAl base alloy material. KEYWORD: Spherical plain bearing; TiAl based alloys; modal analysis

Magnesium matrix composites reinforced by three dimensional (3-D) network structure were fabricated by pressure-less infiltration technology. The 3-D network structure reinforcement and its composites exhibited special topology structure and different fracture characteristic. Metal matrix fractured in a ductile mode is manifested by small dimples and craters on the fracture surface. When the volume fraction of reinforcement is not in excess of 6%, the composite had an improved fracture toughness. This is because of the relatively homogeneous Si3N4 particles distributed in the metal matrix and the occurrence of interface reaction product such as MgAlO2 spinel phase. With the increases of volume fraction of reinforcement (>6%), the fracture toughness decreases slowly at the initial stages and then decreases rapidly towards the end. Therefore, the main fracture failure mechanisms consist of crack nucleation, growth, coalescence and crack propagation.

In order to design a new kind of low-cost high-temperature ferrite–austenite duplex alloy, the effects of carbon and chromium on the alloy solidification structure and properties have been investigated with orthogonal experiments. The addition of carbon promotes strongly the formation of austenite and that of carbides in the alloy solidification structure and refines the alloy grains. With the increase of carbon content, the alloy high temperature strength and oxidation resistance at 1250°C improves at first, but then begins to deteriorate greatly when the carbon content exceeds 0.15%. The addition of chromium facilitates the formation of ferrite in the alloy solidification structure. As the chromium content increases, the alloy rupture strength at 1250°C initially is enhanced, but then reduces rapidly, while the alloy oxidation resistance improves continuously.

In this paper, AlCrFeNi high entropy alloy coating was fabricated on the surface of Q235 steel using hot pressing sintering process. The coating has the controlled thickness size and excellent mechanical properties. Scanning electron microscopy (SEM), XRD and hardness testing method were used to study the morphology, phase structure and hardness of high entropy alloys coating. The lattice distortion plays a significant role in increasing the hardness. Coating formation mechanism caused by the element diffusion under the hot pressing effect is also discussed in the paper. Simultaneously, the dry sliding and oil lubrication wear tests, wear morphology observation and wear mechanism discussion were completed. As the result shows, AlCrFeNi high entropy alloys coating exhibits superior wear resistance either at dry sliding or oil lubrication tests owing to its hard high entropy solid solution structure.

The high temperature oxidation resistance behavior of a AISI430 ferritic stainless steel with a FeCrAISi coating was investigated at 900°C in air by the continuous measurement of the weight gain. The micro-structural characterization was performed by scanning electron microscopy (SEM) and the composition was determined by energy dispersive spectroscopy (EDS). The FeCrAISi coating was found to possess good resistant to oxidation at 900°C in air. The results confirmed that the good oxidation resistance of the FeCrAISi coating was attributed to formation the thin a-Al 2 O 3 phases on the coatings' surface and at the substrate/coating interface.