Dry Wear Tests Research Articles

A comparative analysis of the abrasion wear characteristics of industrial wastes filled glass/polyester composites based on the design of experiment and neural network

AbstractThis article presents the abrasion wear behaviour of different industrial wastes filled glass/polyester composites. Two types of fillers such as fly ash and granite dust are chosen with different weight proportions along with polyester and glass fiber for fabricating the composite using hand layup route. Abrasion wear properties of the developed composites are studied in the dry sand abrasion wear test rig as per the ASTM‐G‐65 standard. The experiments were conducted based on Taguchi design. Between the two fillers, granite filled composite showed better abrasion resistance property as compared with fly ash. Normal load and filler content are found to be the most influential factor for the abrasion loss of the composites followed by abrading distance and sliding velocity. The results are predicted using neural network and also compared with the experimental and regression model data. Abraded surfaces are examined by the SEM to ascertain the different wear mechanisms responsible for abrasion loss of material.

Evaluation of wear mechanisms in additive manufactured carbide-rich tool steels

Advances in additive manufacturing present the opportunity to design tool steels with higher carbon contents than previously possible with conventional manufacturing. A new class of carbide-rich tool steels with 8%, 20% and 25% volume fraction carbides has been developed using electron beam melting. Reciprocating ball-on-plate dry wear tests were performed to investigate the macro tribological performance of these materials. In-situ scratch wear tests were also performed to assess wear degradation effects at a more fundamental level. The main macro wear mechanism was oxidation with adhered iron oxide islands in all carbide-rich tool steels and the sliding of oxide particles caused three body abrasive wear in the lowest carbide containing material. Surface material removed from the counterbody and formed adhesive iron oxide islands over the oxidized carbide-rich tool steel surface. The compacted oxide islands initially formed at the edges of embedded carbides and then evolved to encompass the entire wear scar. The wear damage was assessed quantitatively through laser profilometry. The lowest wear damage was observed in the 20% carbide tool steel which also had the lowest coefficient of friction on moving average of 0.52±0.01 compared to the 8% and 25% carbide tool steel having on moving average 0.66±0.03 and 0.61±0.03 respectively. In-situ scratch wear tests revealed the potential plastic deformation mechanism of the matrix underneath the oxide film. The deformed matrix of 20% carbide tool steel generated limited wear debris at the interface of the tribo-system and this is surmised to provide better wear and friction performance among the materials considered.

Controllable preparation of micro-textures on WC/Co substrate surface by an integrated laser-dry etching process for improving PVD coatings adhesion

The micro-texture fabricated on the substrate surface of coatings is an established method for enhancing the Physical Vapor Deposition (PVD) coatings adhesion. Currently, laser micromachining is widely used to prepare the micro/nano-texture. Nevertheless, it has a problem of low processing accuracy, such as irregular texture edges and irregular protrusions inside the textures. Here, we propose an ion beam etching (IBE)-assisted laser machining approach to fabricate micro-texture, and the effect of IBE/laser textures on the PVD coatings adhesion is revealed for the first time. The profile evolution mechanism of the micro-textures on the cemented carbide during etching process was investigated. By IBE-assisted laser machining, a ring-shaped microholes array with high precision and controllability was fabricated on the cemented carbide substrate surface. Then, the textured substrates were coated with TiAlN materials using cathode arc-evaporation technique. The scratch tests and dry wear tests on the coatings with the textured substrates were carried out, demonstrating that the IBE/laser textured coatings exhibited higher adhesive strength compared to that of the untextured and laser textured ones. Thus, the IBE-assisted laser machining shows a great potential in the preparation of high precision micro-textures for enhancing PVD coatings adhesion.

Studies on mechanical, thermal and tribological properties of carbon fibre-reinforced boron nitride-filled epoxy composites

This research focuses on the static mechanical, thermal and tribological properties of carbon fibre epoxy (CF/Ep) composites filled with boron nitride (BN) micro-filler powder (BN-CF/Ep). The mechanical properties studied were tensile, flexural, interlaminar shear strength and hardness. The thermal properties studied were dynamic mechanical and thermogravimetric analyses which were analysed through dynamic mechanical analyser and thermogravimetric analyser, respectively. The curing ability and dispersion of BN filler in the Ep and composites were investigated through differential scanning calorimetry, Fourier-transform infrared spectra and scanning electron microscopy. The tribological properties focused were three-body abrasion and dry sliding friction and wear conduct. Three-body abrasion tests were studied with silica sand of 212 µm particle size, 30 N load, 2.38 m s−1 sliding velocity and variable abrasive distances of 250 m, 500 m, 750 m and 1000 m. The dry sliding wear tests were performed using pin-on-disc (POD) wear experimental set-up with 60 N load, 3 m s−1 sliding velocity and variable sliding distances of 1000 m, 2000 m and 3000 m. The results followed the trend of BN1% > BN3% > BN5% composites in all mechanical properties. The carbon fabric reinforcement along with the BN-Ep matrix improved enormously all the mechanical properties except impact resistance. Further, it was exhibited that 1 wt% BN into CF/Ep prompts better mechanical properties with predominant damping capacity and thermal stability. Both the dry sand abrasive wear and POD test outcomes revealed that all BN-CF/Ep composites prompt predominant wear resistance. CF along with BN improves enormously the wear resistance with friction coefficient. Further, it was exhibited that 1 wt% BN into CF/Ep in both three-body abrasive and POD tests prompts better wear resistance. Generally speaking, it was presumed that BN-CF/Ep gracefully and successfully improved the mechanical, thermal and tribological properties and morphology of Ep for various mechanical, electrical components and load-bearing applications used in automotive and engineered applications.

Impact of the multilayer approach on the tribocorrosion behaviour of nanocrystalline electroless nickel coatings obtained by different plating modes

This study aims to investigate the tribocorrosion behavior of electroless nickel coatings fabricated by three different means. Multilayered coatings were produced by consecutively stacking three NiP layers with the same phosphorous (P) content. This was accomplished by pausing the plating following each layer growth for sample cleansing and chemical replenishment of the electrolyte. For comparison purposes, two different monolayered coatings were produced in a continuous manner. One of them involved chemical replenishment of the electrolyte (R-monolayer) whereas no action was taken on the other one during the total plating time (Ur-monolayer). The results showed that all the coatings exhibited similar wear volumes under dry wear tests wherein the Ur-monolayer coatings developed fatigue cracks which traversed the coating thickness. Tribocorrosion tests were carried out in a NaCl 3.5 wt% solution and they showed tribolayer formation in all the studied conditions. Moreover, monolayered coatings exhibited fatigue cracks and higher worn volumes than the multilayer ones. The presence of interphases in the multilayer coatings, which originated from pausing the electroless plating, allows enhancing their load bearing capability. Thus, multilayer coatings cope better with the stress derived from the applied normal load and sliding motion during tribocorrosion tests, which translates into a lower plastic deformation of the coatings and 3.5 times smaller worn volumes under the same testing conditions.

A New Ternary Alloy Ti26Zr24Nb for Biomedical Application: Behavior in Corrosion, Wear, and Tribocorrosion

Titanium (Ti)-based alloys with only β-phase have arisen the interest of academics and industrials for bone implants due to their mechanical properties close to those of hard tissues, and for the capability of allowing with β-stabilizers, totally biocompatible elements like Nb, Ta, and Zr. However, there is no consensus about the most adequate composition and, in many cases, tribocorrosion behavior is not considered during their development. New ternary alloy Ti26Zr24Nb as biomaterial is the matter of study of this work regarding wear and corrosion resistances, and the tribocorrosion behavior of this alloy in contact with pH 7, deaerated Hanks solution at 37 °C to simulate a body fluid. All samples have had surface prepared according to the same protocol and a subtract characterization previously and after the electrochemical, dry wear, and tribocorrosion experiments. Results showed high corrosion resistance, with constant open circuit potential (~ − 200 mV) and low corrosion current density (~ 0.9 × 10−8 A/cm2) and important pitting resistance, as well as higher coefficient of friction (COF) for both wear (0.69) and tribocorrosion (0.65) tests than those reported in the literature and, additionally, less wear under tribocorrosion condition compared to dry wear test.

Study of Dry Wear Behavior and Resistance in Samples of a Horizontally Solidified and T6/Heat-Treated Automotive AlSiMg Alloy

To investigate dry wear behavior in an aluminum-based automotive alloy, transient horizontal solidification experiments using a water-cooled directional solidification device have been performed with the Al7Si0.3Mg alloy (wt%). Samples of the as-cast ingot at positions (P) 2, 4, 6, 40, and 80 mm from the cooled interface were subjected to precipitation hardening heat treatment (T6-type). The heat treatment has been applied under the following conditions: solution treatment for 3 h at 520 ± 2 °C, followed by quenching in warm water (70 ± 2 °C), aging for 3 h at 155 ± 2 °C and air-cooling. Dry wear tests were performed on both the as-cast and heat-treated samples. The wear tests were carried out by rotary-fixed ball wear machine means. The analyzed parameters were solidification growth and cooling rates (VL and TR), secondary dendritic spacings (λ2), and wear volume and rate (WV and WR). An interrelation between these parameters has been conducted and experimental mathematical equations have been proposed to characterize the WV and WR dependence on P, VL, TR and λ2. The T6-heat treatment has affected the length of the as-cast dendritic scale, increasing the λ2 values as well as the wear features of the investigated automotive alloy. Finer and coarser dendritic microstructures inherited better wear resistance for the as-cast and heat-treated samples, respectively. An evaluation by occupied area fraction (%IRAF) of interdendritic regions on wear resistance in the as-cast and heat-treated samples has been performed. It has been observed higher and lower IRAF values in the as-cast and heat-treated samples, respectively.

Effect of Ag concentration on structure and wear behaviour of coatings formed by micro-arc oxidation on Ti6Al4 V Alloy

ABSTRACT Micro-arc oxidation (MAO) coating was prepared on Ti6Al4 V alloy in the electrolyte based on different ratios of calcium acetate and a fixed ratio of sodium phosphate with/without Ag additive. The surface, elemental and phase compositions, and dry wear tests of the MAO coating were analysed. The X-ray diffraction results presented that the MAO coating formed rutile, anatase and hydroxyapatite. The results show that the coating performance was improved when Ag additives were included. The wear resistance of the MAO coatings was increased by the addition of Ag.

Effect of plasma-assisted laser pretreatment of hard coatings surface on the physical and chemical bonding between PVD soft and hard coatings and its resulting properties

This research reveals for the first time, how different surface pretreatments (including mechanical polishing, plasma etching, femtosecond laser texturing, and plasma-assisted femtosecond laser texturing) on the PVD hard coatings impact the physical and chemical bonding between PVD soft and hard coatings and its resulting properties. Therefore, the as-deposited TiAlN coatings were served as substrates for the following pretreatments and the deposition of WS2 soft coatings. The scratch tests and dry wear tests were carried out to investigate the adhesion and tribological performance of these WS2/TiAlN soft/hard composite coated samples. Results show that uniform and periodic nano-textures are fabricated on the TiAlN coatings surface by the plasma-assisted laser texturing, which results in high compressive stress and increased surface activity. Thus, the critical load of WS2 coatings deposited on the plasma-assisted laser textured TiAlN substrates (FN = 46 N) exhibits higher values in comparison with the WS2 coatings deposited on untreated TiAlN substrate (FN = 28 N). And, an obviously increasing in wear life of WS2 coatings from 2400 s to 5200 s is achieved by plasma-assisted laser texturing. Additionally, the growth mode of WS2 coatings deposited on the plasma-assisted laser pretreated TiAlN substrare is changed from Volmer–Weber model to Stranski–Krastanov model.

Tribological and electrochemical corrosion performanceanalysis of Hastelloy C276 under different loading conditions

Hastelloy C276, a Ni-Cr-Mo wrought alloy and generally considered as a versatile corrosion resistant alloy, is investigated for dry sliding wear against an EN 31 stainless steel (hardness 60 HRC) at 298 K. The tribological properties such as frictional force, Coefficient of friction and the wear rate on the material surface at different sliding distance are examined under different loading conditions. In the dry wear test at 40 N load, the wear rate increased by 300% as compared to 10, 20, 30 N loading conditions.The experimental results indicated reduction in coefficient of friction values and thus an increase in the frictional force with the increase in normal load. The Scanning Electron Microscope images of worn out surfaces confirm that the delamination and adhesion causes the material removal from the surface in dry sliding. Further, the analysis of the hardness characteristics of worn out surfaces shows surface hardening during sliding wear processunder 40 N loads. The study on the corrosion wear behaviour in the sulphuric acid showed a significantly lower value of corrosion rate (0.0016579 mm/y in H2SO4 solution) in comparison to other alloys frequently used in industries.

Comparative study of mechanical performance between Al–Graphite and Cu–Graphite self-lubricating composites reinforced by nano-Ag particles

Copper and aluminum metals are classified relatively as softer materials that possess comparatively poor mechanical and wear characteristics; accordingly, this study has aimed an attempt to improve their properties and compare between them. At the present work, both copper and aluminum metals were used separately as a matrix composite for a comparative study. They reinforced with a fixed content of 4 vol% graphite as a solid lubricant and various content of 0, 1, 2, 3, and 4 vol% silver nanoparticles. The pure metals and the hybrid nanocomposites were manufactured by utilizing the powder metallurgy technique. Mechanical properties such as hardness, diametral compressive strength, and tensile strength were studied. Moreover, a dry wear test was performed by applying various loads of 5, 10, 15, and 20 N with constant sliding distance and speed of 1810 m and 1.5 m/s, respectively. In order to interpret the results and prove the preparation goodness, Field Emission Scanning Electron Microscope (FESEM) and Energy-Dispersive X-ray (EDX) analysis were employed to characterize the as-received composite powders, worn surface, and wear debris morphology. The results were revealed that the microhardness, diametral compressive strength, tensile strength, friction coefficient, and wear resistance were improved significantly by increasing silver nanoparticle content up to 2 vol% and 3 vol% in aluminum and copper matrix composites, respectively, and then deteriorated gradually as compared with pure metals. Convergence was observed in the wear rate results between the copper and aluminum matrix composites in the silver content of 2 vol%. Besides that, the increment in applied loads was associated negatively with the wear resistance. Lastly, the impact of improving silver nanoparticles content on strengthening the copper matrix composite is higher than aluminum matrix composite.

Microstructural Characterization and Evaluation of Sliding Wear of Hastelloy C276 under Different Loading Conditions

Hastelloy C276 is investigated for dry sliding wear against an EN 31 stainless steel (hardness 60 HRC) at 298 K. The tribological properties such as frictional force, coefficient of friction and the wear rate on the material surface at different sliding distance are examined under different loading conditions. In the dry wear test at 40 N load, the wear rate increased by 300% as compared to 10, 20, 30 N loading conditions. The experimental results indicated reduction in coefficient of friction values and thus an increase in the frictional force with the increase in normal load. SEM images of worn out surfaces confirm that the delamination and adhesion causes the material removal from the surface in dry sliding. Further, the analysis of the hardness characteristics of worn out surfaces shows surface hardening during sliding wear process under 40 N loads.

Experimental investigation on chromium-diamond like carbon (Cr-DLC) coating through plasma enhanced chemical vapour deposition (PECVD) on the nozzle needle surface

This study emphases the reduction of droplet defect in nozzle needle during the application of Cr-DLC coating on the substrate. The coatings were carried out in the highly sophisticated chamber with attached coating setup under the vacuum atmosphere. The materials were assessed in terms of their adhesiveness, hardness, wear resistance, and microstructural morphology. The dry wear test result reveals the appreciable outcome of nitrogen (N2) flushing on quality of interfacial bonding. The indentation confirms the superior morphology of coated substrates but yet insufficient to resist crack propagation due to weak in adhesiveness of chromium (Cr) layer under non-N2 flushing. Scanning electron microcopy (SEM) embedded with energy dispersive X-ray (EDX) was deployed for analysis of cross-sectional coated of substrate. The statistical results claimed that the samples rejection without N2 flushing was showed up to 1.2%. However, the results revealed that Cr-DLC coating with N2 flushing reduced droplet defect and gain remarkable performance over a wide range of samples. Consequently, this novel methodology was employed to assess the coating performance by using a performance index based on tribological properties.

Dry sliding and abrasive wear behaviour of Al-7075 reinforced with alumina and boron nitride particulates

Abstract Present research examination focuses on the surface morphology; mechanical properties and wear conduct of Al-7075 metal matrix composites reinforced with alumina and hexagonal boron nitride fillers. Particulate reinforced Al-7075 metal matrix composites were manufactured following the two step stir casting method with differing the weight percentage (2.5 and 5) of reinforcement. Uniform dispersion of alumina and hexagonal boron nitride in pure alloy was verified by optical microstructure. The fabricated samples were subjected to abrasion using dry sand rubber wheel abrasive wear test rig by varying the abrading distance and the applied normal load. Silica sand of particle size 350–400 µm was used as abrasive medium. Mechanical and dry sliding wear test results indicated that both alumina and hexagonal boron nitride fillers show improved mechanical properties and wear resistance. From the abrasive wear test results, it was recognized that the wear resistance of composites is increased by increasing the weight percentage of reinforcements and the reinforced composite gave better resistance against abrasion than the control sample (Al-7075). Further, it was adjudicated that 5 wt% micro hexagonal boron nitride reinforced Al-7075 composite prompts predominant abrasion resistance. Finally, it was presumed that hexagonal boron nitride and alumina fillers gracefully and successfully improved morphological, mechanical, and also the wear properties of Al-7075 alloy for various engineered load-bearing applications.

Analysis of the Tribological Properties of Commercial Pure (CP) Aluminum Developed by Chip Consolidation through Equal Channel Angular Pressing (ECAP)

The goal of this research work is to study the role of equal channel angular pressing on consolidation behavior of machined chips of CP Al through ECAP. The chips are collected by orthogonal cutting with cutting edge angle 75° and depth of cut 0.2 mm. The ECAP die with Φ = 90° (channel angle) and Ψ = 20° (corner angle) is used for consolidation of machined chips. The consolidation is done by pre-heating the chips at 200°C upto four passes through processing route BC. The maximum density of 99% and hardness of 94 HV was obtained after 4 ECAP passes. Tribological properties is evaluated by Pin-on-disc dry wear testing for three different loads at a constant sliding speed 750 RPM and distance of 5 kms. Chip consolidated CP Al is inferior in wear resistance with as-received CP Al owed to localised debonding of chips with the sliding disc.

Low-cost Zr-based bulk metallic glasses for biomedical devices applications

Toxic element-free and low-cost Zr-based bulk metallic glasses (BMGs) with a property combination of high glass forming ability, large room-temperature plasticity and good biocompatibility are vital candidates as biomedical devices materials. In the present work, the critical diameter (dmax), thermal glass stability, room-temperature mechanical properties, cytotoxicity, corrosion and wear resistances of a series of Zr63.5-xHfxAl9Fe4.5Cu23 (x = 0.0, 1.5, 3.0, 4.5, 6.0, at.%) alloys have been investigated. The Zr60.5Hf3Al9Fe4.5Cu23 (x = 3.0) BMG alloy is found to combine a centimeter scale dmax with large room-temperature plasticity (ɛP = 4.0%). The electrochemical and immersion tests showed the BMG exhibits good corrosion resistance in phosphate buffered solution (PBS) open to air at 37 °C. The passive current density is 9.2 × 10−9 A/cm2, which is one order of magnitude lower than Ti6Al4V alloy at same condition. In addition, the cytotoxicity tests reveal higher cell viability with CCD-986sk cells on the BMG substrate than on Ti6Al4V alloy, showing that the BMG had good biocompatibility. Cell morphologies on the BMG and Ti6Al4V substrates exhibit better cell adhesion of the BMG in comparison with that of Ti6Al4V alloy. Furthermore, the dry wear test shows the wear mass loss is <1/4 of Ti6Al4V alloy at same condition. The attainment of the combination of lower cost and excellent properties suggests that the Zr60.5Hf3Al9Fe4.5Cu23 BMG can be a promising biomedical device material.

Tribological investigation of MgO/Al2O3 ceramic composite with the inclusion of nano CuO in dry abrasive wear test

This paper aims to investigate the tribological influence of nano sized (∼50 nm) copper oxide (CuO) into the magnesium (MgO) based alumina (Al2O3) ceramic composite in a hard-abrasive sliding condition. Sliding wear test was performed to find the frictional and wear behavior of the specimens against abrasive silicon carbide (SiC) interface by means of a rotary pin-on-disk tribometer. Nano CuO added specimen significantly diminished both friction coefficient and wear rate by ∼42.94% and ∼38.30%, respectively as compared to base MgO/Al2O3 specimen. Mending effect of nano CuO by providing a smooth layer was expected to be the main lubricating mechanism against rough abrasive wear surface. Delamination and two body abrasion were the predominant wear mechanism which was investigated using field emission scanning electron microscopy (FESEM) coupled with energy dispersive x-ray spectroscopy (EDS). Different phases of the compounds were identified by x-ray diffraction (XRD) analysis.

Enhanced Wear Resistance of 316 L Stainless Steel with a Nanostructured Surface Layer Prepared by Ultrasonic Surface Rolling

The low hardness and poor wear resistance of AISI 316 L austenitic stainless-steel sabotage its outer appearance and shorten its service life when it is subjected to sliding. In this paper, the single-pass ultrasonic surface rolling (USR) process was used to modify the surface of 316 L austenitic stainless steel. A nanostructured surface layer with a depth span of 15 μm was fabricated. Dry wear tests of USR samples were performed on a ring-on-block tester at room temperature, and the results were compared with those for the as-received sample. The USR sample showed a significant reduction in wear mass loss and an improved hardness, as well as a decreased surface roughness. The detailed wear mechanism was also investigated by SEM observations of the worn surfaces. It was indicated that oxidation and abrasive wear, accompanied by mild adhesion, dominated the wear of USR 316 L stainless steel at both low and high speeds. The superior wear performance of USR 316 L was attributed to its nanostructured surface layer, which was characterized by a high hardness and thereby suppressed the severe abrasive wear. The results provided an alternative approach to modifying the surface of 316 L stainless steel, without changing its surface chemical components.

Increasing wear and corrosion resistance of tool steel by anodic plasma electrolytic nitriding

This paper considers the effect of the anodic plasma electrolytic nitriding (PEN) in a solution of ammonium nitrate and ammonium chloride on wear and corrosion resistance of tool steel including its microhardness and surface roughness. An X-ray diffractometer and scanning electron microscopy were used to analyse the phase composition and structure of the modified surface. Dry wear test of the nitrided, hardened and untreated samples was carried out. The effect of the processing temperature on the corrosion resistance of the nitrided samples was examined by potentiodynamic polarization in the 3% solution of sodium chloride. The nitrate-based electrolyte is shown to provide the formation of the outer oxide layer and hardened sublayer containing martensite and retained austenite. The anodic PEN of steel for 5 min results in an increase in microhardness to 1280 HV50 and a decrease in wear rate by 5.5 times compared with the hardened sample. It has been established that the corrosion current density decreases from 21 μA/cm2 in untreated steel to 3.7 μA/cm2 after PEN of 700 °C.

Effects of Waste Eggshells addition on Microstructures, Mechanical and Tribological Properties of Green Metal Matrix Composite

Abstract Chicken eggshell (Es) waste is an industrial byproduct, and its disposal constitutes a severe environmental risk. Eggshell is a new engineering reinforcement retaining excellent properties such as low density, renewable, eco-friendly, and high thermal stability. The current research aims to study the effects of eggshell particles addition on microstructures, mechanical and tribological properties of aluminium/eggshell green metal matrix composites (MMCs). In the present work Al–Es metal matrix composite is produced by powder metallurgy processes. SEM with EDX and XRD were used to examine the microstructures and the compounds that arise during the sintering process of the produced composites. Six tests were conducted on the produced samples including; dry wear test, micro Vickers hardness, and ultimate compressive strength. The results showed that the addition of 3 wt. % of eggshell improved wear resistance (65%), compressive strength (40%) and hardness (15%). At 6 and 9 wt. % of eggshell, negative results appeared.