Dominant Wear Mechanism Research Articles

Tribological behavior of SiC reinforced AZ91D composites manufactured by semisolid injection molding

Semisolid injection molding is a novel and ideal process for manufacturing particle reinforced magnesium composites. The main purpose of this article is to reveal the wear mechanism of SiC/AZ91D composite prepared by this method. AZ91D Mg alloy and its composites reinforced with 1 % and 2.5 % SiC particles were manufactured by the semisolid injection molding method and their microstructure and wear behavior were investigated. The composites are composed of a Mg matrix, consisting of unmelted AZ91D particles distributed in a resolidified Mg base, and uniformly-dispersed SiC particles. The dry wear tests showed that adding SiC reinforcement increases the friction coefficient, enhances the wear resistance at the low loads of 5 N and 10 N, but reduces the wear resistance at the high load of 20 N. The dominant wear mechanism is abrasive wear, accompanied by small contributions from adhesive and oxidative wear.

Microstructure, mechanical and tribological properties of APC/Al laminated composites prepared by hydrothermal carbon adsorption on plates

Amorphous carbon (APC)/Al laminated composites were prepared by hydrothermal carbon adsorption on plates (HTCAP) and vacuum hot-press sintering process. The effect of the glucose solution concentration on the microstructure, mechanical properties and tribological properties was investigated. The results indicate that APC is uniformly distributed between layers and has good interfacial bonding with the matrix through the diffusion of Al. As the glucose solution concentration increases, the interlayer hardness, ultimate tensile strength and elongation first increase and then decrease, while the wear rate shows the opposite trend and the coefficient of friction (COF) gradually decreases. A maximum elongation of 16.4% and a minimum wear rate of 0.344×10−5 mm3/(N·m) are achieved at a glucose solution concentration of 0.3 mol/L. Adhesive wear is the dominant wear mechanism of APC/Al laminated composites. The improvement in wear resistance is attributed to the formation of uniform APC lubrication film on the wear surface.

Wear mechanism transforming of ultrafine-grained pure titanium by multi-axial forging and low-temperature annealing

The effect of microstructure and mechanical properties of submicro grained commercial pure titanium (CP–Ti) on the wear mechanism is still unclear. In the present work, CP-Ti samples were subjected to multi-axial forging (MAF) and low-temperature annealing treatment to prepare ultrafine-grained (UFG) material. The mechanical properties, microstructure, and tribological characterization between coarse-grained (CG) sample and UFG samples were comparatively studied. The results showed that the MAF sample could reach a grain size of 165 nm, while its grains coarsened slightly after low-temperature annealing. The MAF sample had the highest strength and hardness and the lowest coefficient of friction, but only a 7.3 % decrease in wear rate compared to the CG sample. The 400 °C annealed MAF sample possessed a good combination of tensile strength (814 MPa) and elongation (18.6 %), resulting in the lowest wear rate of 16.8 × 10−5mm3/(N∙m). The dominated wear mechanisms of the CG sample, MAF sample and 500 °C annealed MAF sample were abrasive wear, adhesive wear and delamination wear, while the primary mechanism of the 400 °C annealed MAF sample was abrasive wear and adhesive wear. It was found that the wear mechanism transforming, higher hardness and sufficient work hardening could be responsible for lower wear rate of the 400 °C annealed MAF sample. The 400 °C annealed MAF sample showed a thinner and more homogeneous deformation layer near the worn surface, and its thickness of deformation layer was about 8 μm.

Dual-phase high-entropy carbide/boride ceramics with excellent tribological properties

Tribological characteristics of fine-grained dual-phase high-entropy carbide/boride ceramics were investigated using the ball-on-flat dry sliding method in air, applying linear reciprocation motion with SiC counterpart. Detailed fractographical analyses were used for the characterization of the deformation and damage mechanisms. The investigated system with composition (Ti0.14Zr0.2Nb0.2Hf0.2Ta0.26)C + (Ti0.38Zr0.18Nb0.22Hf0.115Ta0.105)B2 showed density with value 8.72 g/cm3 and very high hardness of HV1 29.4 ± 2.0 GPa. The friction coefficient at the test with 5 N was 0.56 and during the test with 10 N and 25 N loads were 0.48 and 0.5, respectively. The effective wear rates at the loads of 5 N and 25 N were very similar with values of 7.93 × 10−7 mm3/Nm and 6.63 × 10−7 mm3/Nm. At load 50 N the effective wear rate is significantly higher with a value of 9.11 × 10−6 mm3/Nm. Detailed fractography revealed that the dominant wear mechanisms at loads of 5 N and 25 N were an oxidation-driven tribochemical reaction and tribo-layer formation in boride grains and mechanical wear in carbide grains and at the load of 50 N fracture of boride and carbide grains and formation of chemically complex tribolayers.

Microstructure and Wear Behavior of Heat-Treated Mg-1Zn-1Ca Alloy for Biomedical Applications.

The microstructure and wear properties of a Mg-1wt.% Zn-1wt.% Ca (ZX11) alloy with different heat treatments have been investigated. The ZX11 alloy was tested in the as-cast state and after different heat treatment conditions: solution-treated (at 450 °C for 24 h), peak-aged (solution-treated + aged at 180 °C for 3 h), and over-aged (solution-treated + aged at 180 °C for 24 h). The microstructure of the as-cast sample showed a continuous intermetallic phase at the grain boundaries, while the heat-treated samples exhibited discrete precipitated particles within the grains. To evaluate the wear behavior, the samples were tested using a pin-on-disc configuration, where the wear rates and friction coefficients were measured at different loads and sliding speeds. An AZ31 magnesium alloy was used as the counterbody. The worn surfaces and the wear debris were studied to identify the main wear mechanisms corresponding to each test condition. The results indicated the presence of abrasion, oxidation, and adhesive wear mechanisms in all testing conditions. In the as-cast state, delamination and plastic deformation were the dominant wear mechanisms, while they were less relevant in the heat-treated conditions. The peak-aged samples exhibited the lowest wear rates, suggesting that modifying the distribution of intermetallic precipitates contributed to enhancing the wear resistance of the alloy.

Evaluation of Machining Variables on Machinability of Nickel Alloy Inconel 718 Using Coated Carbide Tools

The current work was undertaken with the research aim of experimental examination of tool wear, surface roughness and burr formation during the micro-milling of Inconel 718 using different coated tools. Inconel 718 is one of the most widely used materials for purpose-oriented utilization owing to its preferred mechanical and physical properties, including high strength and corrosion resistance. On the opposite end, the machining of Inconel 718 poses certain machinability challenges, which significantly elevates tool wear and subsequently surface roughness. Cutting speed, feed rate and depth of cut were selected as variable machining inputs. With reference to tool wear, all input variables were found to be significant, with tool coating having the highest contribution ratio of 36.19%. In case of surface roughness, cutting speed and tool coating were identified as effective input parameters with contribution ratios of 51.24% and 34.27%, respectively. Similarly, depth of cut proved to be an influential factor for burr height formation (in both up-milling and down-milling), whereas feed rate had the highest contribution ratios for burr width formation during up-milling and down-milling, i.e., 39.28% and 36.26%, respectively. Consequently, contour plots for output responses were drawn between significant parameters to analyze machinability. One of the vital research outcomes was the identification of a tool coating parameter that is significant for all four analyzed aspects of burr formation. In addition, regression equations were formulated for machining responses. The best- and worst-case scenarios for individual input parameters, as identified from main effects plots, were validated during confirmatory experimentation. Moreover, effects of input variables on output response were characterized using close-up imagery, and dominant wear mechanisms were also identified. The utility of the research is underlined by the optimization of the sustainability and productivity of the manufacturing process.

Investigation of the wear behavior of FeNi36 alloy cut by WEDM method under different loads

PurposeFeNi36 (Invar-36) alloy is widely used in the fabrication of molding tools in aerospace industries but there remains a need to improve its wear and friction performance due to its relatively low hardness. The formation of a heat affected zone (HAZ) on the surface of Invar-36 cut by wire electric discharge machining (WEDM) is promising to enhance its tribological properties. This study aims to investigate the tribological performance of WEDM-treated Invar-36 via a ball-on-disk tribometer in dry-sliding conditions.Design/methodology/approachThe untreated and WEDM-treated Invar-36 surfaces were reciprocated against an alumina ball at a sliding velocity of 40 mm/s, a stroke length of 10 mm and a sliding duration of 125 min under loads of 5, 10 and 20 N. The worn surfaces were characterized using a 2D profilometry and a scanning electron microscope equipped with energy-dispersive spectroscopy.FindingsThe results showed that the WEDM-treated surface had a superior friction coefficient and wear resistance in comparison to the untreated surface, due to the grown HAZ. There was found to be a 9.3%–11.4% decrease in the friction coefficient and a 47%–57% reduction in the wear volume after the WEDM treatment. Both the untreated and WEDM-treated Invar-36 surfaces found abrasion and plastic deformation as the dominant wear mechanisms.Originality/valuePrevious works have not focused on the tribological performance of the WEDM-treated Invar-36 extensively used for molding tools in aerospace industries. Our findings provide compelling evidence that the WEDM treatment improved the wear and friction performance of Invar-36 alloy because of the grown HAZ.

Microstructural Modification of Cold-Sprayed Ti-Cr3C2 Composite Coating by Laser Remelting

Laser processing is an effective post-treatment method for modifying the structure and improving the properties of cold-sprayed coatings. In the present work, the possibility of fabricating a hard and wear-resistant Ti-based cermet coating by cold spray followed by laser remelting was studied. A mixture of titanium and chromium carbide powders in a ratio of 60/40 wt.% was deposited by cold spray onto a titanium alloy substrate, which ensured the formation of a composite coating with a residual chromium carbide content of about 12–13 wt.%. The optimal values of laser beam power (2 kW) and scanning speed (75 mm/s) leading to the qualitative fusion of the coating with the substrate with minimal porosity and absence of defects were revealed. The microstructure and phase composition of as-sprayed and remelted coatings were examined with SEM, EDS and XRD analysis. It was shown that the phase composition of the as-sprayed coating did not change compared to the feedstock mixture, while the remelted coating was transformed into a β-Ti(Cr) solid solution with uniformly distributed nonstoichiometric TiCx particles. Due to the change in microstructure and phase composition, the remelted coating was characterized by an attractive combination of higher microhardness (437 HV0.1) and lower specific wear rate (0.25 × 10−3 mm3/N × m) under dry sliding wear conditions compared to the as-sprayed coating and substrate. Laser remelting of the coating resulted in a change in the dominant wear mechanism from oxidative–abrasive to oxidative–adhesive with delamination.

Temperature‐dependent wear characteristics of ZE41 magnesium alloy under air and inert environments

AbstractDry sliding wear behaviour of ZE41 magnesium alloy was evaluated under the air and argon environment at room temperature, 125 °C, and 250 °C. The coefficient of friction was increased with increasing the test temperature. At room temperature and 125 °C, the friction coefficient was reduced in the argon environment. However, at 250 °C, the friction coefficient in the argon environment was measured as higher compared to that of the tests conducted in the air environment. The wear rate increased with the increasing temperature. However, a lower wear rate was observed in the case of argon atmosphere than in air for all the test temperatures. Abrasion and delamination were dominant wear mechanisms at room temperature and 125 °C, whereas at 250 °C, thermal softening and shearing were found to be dominant. Furthermore, oxidation wear was observed as the prominent mechanism in the air environment.

Role of multi-walled carbon nanotube particles on the wear behaviour of vacuum hot pressed Mg-AZ91 composite

The demerit of Mg-AZ91 alloy is poor wear resistance. In order to increase the wear resistance and decrease the CoF, MWCNT is reinforced in various wt% (0.5, 1, & 1.5) into Mg-AZ91 by a vacuum hot press technique. The OM image of the specimens shows the strong metallurgical bonding between matrix material, uniform dispersion of MWCNT for 0.5 and 1 wt% composites and agglomeration of MWCNT for 1.5 wt% composite. XRD analysis confirms MWCNT presence and peak shift towards a higher angle in the composites. MWCNT reinforced 1 wt% composite has exhibited the highest hardness values of 97.90 HV0.3, good wear resistance (wear rate = 3.28 × 10-5 g/m) due to the strengthening by grain size reduction and a low CoF value of 0.32 due to the self-lubrication effect of MWCNT. SEM investigation confirms that surface fatigue is the dominant wear mechanism in all specimens.

Dry sliding wear behavior of AA7075 alloy produced by thixocasting

Abstract In this study, the wear behavior of AA7075 alloy produced by thixocasting was investigated. The wear behavior of the AA7075 alloy is examined for three cases: extruded with T6 heat treatment, as-thixocast, and thixocast with T6 conditions. The dry sliding wear test was conducted with a tribometer according to ASTM G-99 standard. The microstructures were characterized by optical microscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray analysis (EDX). The tensile and hardness tests were performed to evaluate the mechanical properties. The AA7075 alloy was successfully shaped by thixocasting. The as-thixocast sample exhibited typical globular structures with multinary eutectic structures along the grain boundaries. The globular grains transform into a polygonal structure, and the grain size increases from 50 μm to 60 μm in the thixocast + T6 sample. This microstructure exhibited excellent wear resistance under dry sliding conditions in the thixocast + T6 sample. The aging treatment with prolonged solution process improved the mechanical properties two times and the wear rate three times for the thixocast AA7075 alloy. Furthermore, the thixocast + T6 sample exhibited a significant decrease in the coefficient of friction with the lowest wear rate compared to the as-thixocast sample. The dominant wear mechanisms are microdelamination, adhesion, and oxidation in all samples.

Study on tool wear mechanism and chip morphology during turning of Inconel 713C by textured inserts

The present study aims to analyze the tool wear mechanism and chip morphology during dry (D) and graphene solid-lubricant (S), turning of Inconel 713C with a new novel textured (honeycomb (T2) and rectangular(T3)) and further compare with the textured dimple tool (T1). In addition, the performances were compared with the untextured tool (T0). The machining tests for all conditions were carried out at different levels of cutting speeds (75 m/min and 150 m/min), feed rate (0.1 mm/rev and 0.2 mm/rev), and a constant level of depth of cut (0.5 mm). Honeycomb-textured cutting tools performed better. Improvements of 33.3 % (T1D), 50 % (T3D), and 75 % (T2D) without graphene and 66.6 %(T1S), 75 % (T3S), and 100 %(T2S) with graphene are observed compared to T0. The primary mechanism for the better performance of T2S was the reduced tool chip contact length (8–50 %), chip width (30.4 %), friction coefficient (57.4 %), chip thickness (17.8 %), and higher shear angle (14.2 %) compared to dry textured and untextured tools at the end of tool life. Additionally, the T2S (solid lubricant-impregnated honeycomb) demonstrates a decrease in equivalent chip thickness (19.8 %) and an increase in shrinkage factor (17.2 %) at worn-out tool life conditions at high cutting speed and feed rate. Under the same conditions, T2S has 27.3 % lower cutting force and 36.2 % lower surface roughness of machined workpieces compared to the untextured tool at the end of tool life. The chip micrograph reveals the chips are shorter, and the chip radius is lower for T2S tools with smooth friction tracks and fine deformed lamella on the free surface of the chip. Under SEM, flank wear, adhesion materials, abrasion, micro-chipping coating peeling, and BUE were dominant wear mechanisms. However, T2S tools effectively reduce Ni elements' diffusion and suppress the built-up edge's adhesion by improving friction characteristics at the tool-chip interface region. Lastly, the outcomes of experimental results suggest that the honeycomb texture for dry machining of Inconel 713C.

Optimizing material selection: A study of erosion-corrosion performance in homogeneous and carbide-containing materials

Erosion-corrosion is a major factor contributing to material loss and reduced useful life of hydro-transport equipment. The combined effect of erosion and corrosion is responsible for high degradation rates. In oil sand mining, materials from different classes are used for various applications depending on the severity of degradation. In this research, we assessed the erosion-corrosion characteristics of four uniform materials (pipeline and abrasion-resistant steels) as well as five materials containing varying types and quantities of carbide (chrome white iron and WC-based overlay). The materials underwent erosion-corrosion testing within a slurry container (comprising 3.5 wt% NaCl + 35 wt% natural silica sand) at a temperature of 45 °C. Under the test conditions, it was found that matrix wear influences the extent of carbide degradation for all carbide-containing materials. To provide good erosion-corrosion resistance, the surrounding matrix that supports the carbide must have sufficient wear and corrosion resistance. This study also identifies the dominant wear mechanisms for both uniform and carbide-containing materials.

Effect of cold spray processing parameters on the microstructure, wear, and corrosion behavior of Cu and Cu–Al2O3 coatings deposited on AZ31 alloy substrate

Cold spray coatings represent a newly emerging and recently implemented approach to enhance the poor wear and corrosion resistance of AZ31 magnesium alloy. In this study, the authors applied pure Cu and Cu-50 wt% Al2O3 composite coatings on an AZ31B substrate using the cold spray deposition method and investigated the effects of gas pressure (1, 2, and 3 MPa) and stand-off distance (1, 2, and 3 cm) on their microstructure characteristics. An increase in gas pressure from 1 MPa to 3 MPa resulted in a decrease in porosity, ranging from 33 % to 38 %, across varying stand-off distances. Increasing the stand-off distance from 1 to 3 cm resulted in a nearly four-fold rise in porosity for 2 and 3 MPa pressures and about 1.5 times for 1 MPa. The porosity increased with higher pressure due to the fragmentation of Al2O3 particles but decreased with greater spraying distance due to reduced Al2O3 retention. Additionally, the incorporation of Al2O3 particles into Cu coatings led to a significant improvement in sliding wear resistance, by up to 50 %, compared to the bare substrate. Abrasive wear and delamination were identified as the dominant wear mechanisms for the composite coatings based on friction coefficient values and micromorphology of wear tracks. Electrochemical results indicated a significant increase in the corrosion resistance of the Cu coating compared to both the bare Mg substrate and Cu–Al2O3 coating, attributed to improved resistance to galvanic corrosion.

The Tribological Behavior of Cast Iron by Laser Surface Texturing under Oil-Lubricated Initial Line Contact for Rotary Compressor

The tribological behaviors of cast iron by laser surface texturing were experimentally compared with the behavior of untextured by unidirectional rotary sliding friction and wear tests under oil-lubricated initial line contact. The friction coefficient and temperature rise were analyzed with the increasing load applied by block-on-ring tests. In addition, the wear loss and wear mechanism were also investigated through the surface topographies analysis. The results showed that the tribological improvement strongly depended on the contact form. For the oil-lubricated initial line contact in this work, the textured surface showed a better frictional advantage with a lower friction coefficient and lower temperature rise. The hydrodynamic effect enhanced the load-carrying capacity of the oil film and increased the film thickness. The friction coefficients were 11~64% lower than those on the untextured one. Meanwhile, the textured surface deteriorated the wear behavior due to the coupling effect between the micro-cutting effect of the texture edges and the material deformations of the counter surface. The material loss induced by abrasive wear and fatigue wear was the dominant wear mechanism. Namely, the laser surface texturing improved the friction properties but reduced the wear resistance.

Tribological behavior of Al matrix composites reinforced by hybrid Cu and SiC under SN500 + G lubricant

Al matrix composites reinforced with hybrid SiC and Cu reinforcement were prepared by powder metallurgy and sintering. The presence of Cu in the composite microstructure has caused the formation of a three-dimensional network of metallic reinforcing phase. Wear tests were performed (50 and 100 N, 1 mm/s, 1000 m) as dry wear and lubricated wear under SN500 base oil containing graphite particles. The friction results showed that the COF under lubricant compared to the dry wear test was decreased by ∼80 %. With increasing SiC/Cu content the wear rate was decreased up to 30 %. The SEM observation of the lubricated worn surfaces showed that adhesive wear was the dominant wear mechanism, which significantly decreased with the tribofilm formation.

Development of interactive friction model for machining considering the instantaneous interfacial characteristics

In this article, the transient and complex tribological characteristics of machining interfaces have been considered for developing a friction model. The interfacial characteristics – a condition where process parameters are in fluctuation rather than being constant – are identified. In an investigation of coated carbide tool wear in machining AISI H13 steel, the dominant wear mechanisms were identified as the abrasion, adhesion, and asperity deformation. Considering the complex loading, transient tribological behaviours, and observed wear mechanisms in machining, an interactive friction model is developed based on the mutually interactive nature of wear-and-friction. The evolution of the coefficient of friction with machining time is considered with different stages of tool wear. The adjusting capability of the developed model with respect to the complex loading is explored. The value of this research is to discover a unique behaviour at interfaces, additionally to identify the transient tribological conditions including wear mechanisms, and for the first time, to develop the interactive friction model for machining that adds scientific contribution to the domain of machining tribology.

Consolidation and wear resistance of Fe based bulk metallic glass composites by spark plasma sintering

High densification and wear resistance are essential for the application of Fe-based bulk metallic glass composites. In this work, Fe-based composites were fabricated by spark plasma sintering. Firstly, under the pressure of 150 MPa, all samples achieved high densification, the microcontact pressure between powder particles decreased with increasing density. Then, as the sintering temperature was increased from 350 °C to 450 °C, the crystalline phases were identified as Fe3Si and Fe2B. The hard borides improved the hardness and wear resistance of composites. Finally, at sintering temperature of 400 °C, the sample exhibited the highest micro-Vickers hardness of 1168.8 Hv and the lowest friction coefficient of 0.59, the coefficient of friction was lower than that of bearing steel. FeSiB BMG composites showed dominant abrasive and oxidative wear mechanisms. FeSiB composites showed excellent hardness and wear resistance, which extends the potential application of bulk metallic glass in the field of engineering structural materials.

Microstructure and wear resistance of in-situ TiC reinforced Stellite 6 coating using PTA cladding

To enhance the durability of copper tuyeres in blast furnaces, it is necessary to apply coatings on their surfaces to protect against wear caused by high-temperature coke. In this study, a series of in-situ synthetic TiC-reinforced Stellite 6 alloy coatings containing a Ni60A interlayer were successfully produced on copper substrates using 5–45 wt% TiFe/Cr3C2 precursor powders. The coatings exhibited excellent metallurgical bonding with the Ni60A interlayer, and an elemental transition zone was formed at the interface between the coating and the interlayer. XRD Rietveld refinement analysis revealed that the T45 coating with 45 wt% of precursor powder showed the highest TiC phase content of 12.27 %, with an average hardness of 658.15 HV0.2, which was 31.2 % higher than that of the Stellite 6 alloy. The wear mechanism of the Stellite 6 coating was plastic delamination at 25 °C, and oxidative wear at 500 °C. As the TiC particle content in the coating increased, the dominant wear mechanism tended to shift towards abrasive wear. The specific wear mechanism of the coating was influenced by the content of coating phases and the operating temperature. The best wear resistance was achieved by the T45 coating, which showed an abrasive wear mechanism at both 25 °C and 500 °C, with a wear resistance of 4.47 and 5.94 times higher than that of the Stellite 6 alloy respectively.

Tribological and corrosion behaviour of medical grade 316LVM steel by low temperature hybrid gaseous nitriding and carburizing

This study approached a low temperature hybrid gaseous nitriding and carburizing at varying temperature and gas composition to develop S-phase layer on 316LVM steel. The hybrid gaseous treatment at 475 °C and 10 % CH4 developed a distinct S-phase layer that is harder (1444 ± 32 HV0.025) than untreated surface. The S-phase layers are effective in reducing specific wear rates by 67 % to 1.19 ± 0.05 × 10−3 mm3/Nm, coefficients of friction by 26 % to 0.49 ± 0.02, and corrosion rate by 23 % to 6.02 ± 0.32 µm/y. Both untreated and treated surfaces had dominant abrasive wear mechanisms but on treated surface spalling holes were observed. This research highlights low-temperature hybrid gaseous nitriding and carburizing is promising for improving 316 LVM steel surface for orthopedic.