Formation Of Tribolayer Research Articles

Nanoindentation and tribology of a (Hf-Ta-Zr-Nb-Ti)C high-entropy carbide

A (Hf-Ta-Zr-Nb-Ti)C high-entropy carbide was prepared by ball milling and a two-step Spark Plasma Sintering process, achieving a single-phase ceramic sample with a high relative density of 99.4 %. The wear resistance of the sample was measured by tribology and micro-scale mechanical behaviour was studied by nanoindentation on both the non-deformed and worn surfaces. Grains and the vicinity of grain boundaries exhibited high hardness values of 38.5 ± 0.5 GPa and 35.5 ± 1.0 GPa with similar Young’s moduli of 562 ± 11 GPa and 547 ± 16 GPa, respectively. The dominant wear mechanism was mechanical wear with limited grain pull-out and fracture, and with a localized and thin tribo-layer formation. The specific wear rate exhibited an increase with the increasing load from 2.53·10−6 mm3/Nm at 5 N to 9.03·10−6 mm3/Nm at 50 N. This was correlated to the decrease of nanohardness of the worn surfaces with increasing wear load, which is attributed to the increased number of microcracks.

Microstructural, mechanical and tribological performances of copper foam modified CFRP composite for pantograph strip

AbstractA novel pantograph strip of copper mesh modified carbon fiber reinforced polymer (CFRP) composite was fabricated by impregnating copper foam with the resin mixture of carbon fiber and flaky graphite, following by mold hot‐pressing technology. Microstructure, mechanical strength, electric conductivity, friction, and wear behaviors of the composite were investigated and analyzed to explore the fracture failure and wear mechanisms. The results show that the composite obtains much lower electric resistance than that of the pure carbon strip used in China's high‐speed railway. Adding carbon fiber can improve impact strength and wear resistance considerably, but has little effect on anti‐friction performance. The electric resistance and tribological performances are graphite dependent, reduced electric resistance and friction coefficient can be obtained with the increase of flaky graphite from 0 to 15 wt% while negligible changes of impact strength and wear rate are found. However, further increasing the flaky graphite to 20 wt%, the wear rate reveals a dramatic rise. High content of flaky graphite contributes to the formation of thick tribolayer with unconsolidated structure. And the tribolayer is easy to curl and worn off from the wear surface, leading to severe wear of the composite during the current carrying friction tests.

Superior Wear-Resistance of Ti3C2Tx Multilayer Coatings.

Owing to MXenes' tunable mechanical properties induced by their structural and chemical diversity, MXenes are believed to compete with state-of-the-art 2D nanomaterials such as graphene regarding their tribological performance. Their nanolaminate structure offers weak interlayer interactions and an easy-to-shear ability to render them excellent candidates for solid lubrication. However, the acting friction and wear mechanisms are yet to be explored. To elucidate these mechanisms, 100-nm-thick homogeneous multilayer Ti3C2Tx coatings are deposited on technologically relevant stainless steel by electrospraying. Using ball-on-disk tribometry (Si3N4 counterbody) with acting contact pressures of about 300 MPa, their long-term friction and wear performance under dry conditions are studied. MXene-coated specimens demonstrate a 6-fold friction reduction and an ultralow wear rate (4 × 10-9 mm3 N-1 m-1) over 100 000 sliding cycles, outperforming state-of-the-art 2D nanomaterials by at least 200% regarding their wear life. High-resolution characterization verified the formation of a beneficial tribolayer consisting of thermally/mechanically degraded MXenes and amorphous/nanocrystalline iron oxides. The transfer of this tribolayer to the counterbody transforms the initial steel/Si3N4 contact to tribolayer/tribolayer contact with low shear resistance. MXene pileups at the wear track's reversal points continuously supply the tribological contact with fresh, lubricious nanosheets, thus enabling an ultra-wear-resistant and low-friction performance.

In situ Tribo-Fluorination for Oil-Less Hermetic Compressor Applications

In the present work, we overview the multidisciplinary development of a regular, lubricated, hermetic compressor which works in an on-off cycle, circular motion, single-speed, many tribological contacts, into an innovative, linear motion, variable displacement, single tribological contact, oil-less hermetic compressor presenting high versatility in terms of refrigerator design, sustainability and improved efficiency. The original approach encompassed the development of new surface engineering procedures applying purpose-oriented phases to soft substrates. Particular emphasis is given to the in situ fluorination of the tribolayer formed in the piston-cylinder tribopair. Although chlorinated halocarbons (CFC) are efficient refrigerants from a thermodynamic point of view, they do have serious environmental implications that have forced the refrigeration industry to switch to more environmentally friendly hydrofluorocarbon (HFC) based refrigerants. The first and most successful alternative to the CFCs was tetrafluorocarbon, particularly tetrafluoroethane (CF3CH2F), aka R134a refrigerant. The current trend to downsizing mechanical systems, smaller clearances, and increased speeds leading to greater energy efficiencies associated with miscibility issues imposing the use of costly, fully synthetic lubricants with the R134a refrigerant gas led to the introduction of a new hermetic compressor design, the Wisemotion®, the first, and until now, unique, oil-free hermetic compressor on the world market. In this context different types of multi-layers, their thickness, substrate material, processing routes, etc., have been studied and optimized. Si-rich hydrogenated DLC (a:C-H) presented enhanced tribological properties when tested under fluorine-rich atmospheres, and semi-industrial scale tests have been carried out to understand this point further. A homemade tribological emulator was developed allowing close-to-real tribopair, atmosphere, and imposed mechanical conditions used in an oil-free commercial hermetic compressor. The tests were carried under different stroke frequencies (5, 20, and 40 Hz) and atmospheres (R134a, ambient air, and argon). Results showed a strong influence of both atmosphere and stroke frequencies. The friction coefficients were significantly lower (~3.8X) for the refrigerant gas atmosphere, attributed to the fluorine and highly disordered graphitic structures rich tribolayers. Under the high frequency (40 Hz), the energy input seems to be a deterrent to the formation of stable tribolayers, and the DLC coating shatters on the first few sliding meters.

Microstructure and Tribological Properties of Plasma-Sprayed CoCrFeNi-based High-Entropy Alloy Coatings Under Dry and Oil-Lubricated Sliding Conditions

The CoCrFeNi-based high-entropy alloy coatings were prepared by atmospheric plasma spraying. The microstructure, phase, microhardness and corrosion resistance of the coatings were characterized. The tribological properties of the coatings sliding against GCr15 balls under dry and oil-lubricated sliding conditions were investigated. The results show that the phase composition of the CoCrFeNiAl coating is mainly BCC phase, accompanied by a small amount of FCC phase and AlCrO3 oxide phase. The oxide phase is mostly distributed at the splat interfaces, which leads to a low cohesive strength and high wear rate under both dry and oil-lubricated sliding conditions. The CoCrFeNiMn coating is composed of FCC phase and relatively large amount of MnCr2O4 oxide phase. High oxides content and good plastic deformation ability contribute to the formation of tribolayer on the worn surface, which promotes excellent wear resistance under both conditions. The CoCrFeNiMo0.5 coating consists of mostly FCC phase and a bit of aggregated Cr2FeO4 oxide phase. Its dominant wear mechanism is abrasive wear.

The role of metal powder properties on the tribology of cold sprayed Ti6Al4V-TiC metal matrix composites

Ti6Al4V-TiC metal matrix composite (MMC) coatings were cold sprayed using spherical and irregular Ti6Al4V powders manufactured with plasma gas atomization and the Armstrong process, respectively. Composite coatings deposited using irregular powders showed higher ceramic retentions and lower porosity compared to spherical powder (SP) coatings. Sliding wear tests were performed at two different normal loads using a spherical WC-Co ball as counterface. Wear test results showed that at similar ceramic contents, spherical powder composites exhibited abrasive wear mechanisms with high coefficients of friction (CoF) and wear rates. In irregular powder (IP) composites, islands of tribolayers, comprised of fragmented TiC and TiO2 particles, resisted the localized shear deformation leading to low wear, and with free carbon from the TiC particles also lowered the CoF. Increase in ceramic content in the IP MMCs to 23% led to higher coverage of wear track area with tribolayers and further lowered the wear rate. At higher load, 23% TiC composite coatings showed a more continuous tribolayer, whereas lower ceramic content MMCs showed no significant formation of tribolayers. The formation of a highly continuous tribolayer at higher load (in 23% TiC MMC), led to extremely low CoF (~ 0.25) compared to other coatings along with low wear rate. Electron channel contrast imaging and transmission electron microscopy analysis of the worn subsurface under the tribolayers showed coarse-grain microstructures compared to the bare regions of the wear track (i.e. without tribolayer coverage). The formation of coarser grain microstructures indicated less stress transfer to the subsurface both due to the high hardness and lubricating nature of the tribolayers.

Formation mechanism and function of tribo-layers in dry sliding wear of TC11 alloy

Dry sliding wear tests were performed for TC11 alloy through a pin-on-disc tribometer at a load of 50 N under different sliding velocities. Tribo-layers always formed on wear surfaces of titanium alloy at different sliding speeds. The formation of tribo-layers depended on the generation, movement, aggregation, transfer of wear debris and tribo-chemistry. Small wear debris and relatively high contact surface temperature were favorable conditions for formation of tribo-oxide layers. Tribo-oxide layers protected the titanium alloy matrix effectively and reduced the wear. The more oxides the tribo-oxide layer contained, the better it protected the matrix.

Graphite oxide tribo-layer formation under boundary lubrication of diesel fuel

Friction and wear of mechanical components (such as engines) is controlled by some kind of boundary films (also referred to as tribo-layer). In some cases, such boundary film is formed on the contact interface due to a tribo-chemical process in the presence of liquid media. In this paper, we demonstrate the formation of graphite oxide tribo-layer on the contact interface of steel in the presence of diesel fuel liquid media. A Raman spectrometer was used to analyse the tribo-layer structure. Although the intensity is low, it is shown that the tribo-layer has a structure of graphite oxide, demonstrated by the presence of D band peak at approximately 1350 cm−1 and G band peak at approximately 1550 cm−1 in the Raman spectra. Such graphite solid films on the sliding surfaces have ability to control friction and wear. This finding demonstrates the possibility of in-situ formation of solid protective film of a tribo-pair components using the working fluid where the use of lubricants is restricted as they contaminate the working fluid.

Spark plasma sintering and dry sliding-wear of ZrC-16.7 vol.% Co cemented carbides

The densifiability by spark plasma sintering (SPS) and the dry sliding-wear behaviour of novel cemented carbides based on micrometre-sized ZrC with 16.7 vol.% Co binder (ZrC–Co), compositionally equivalent to the typical WC–10 wt%Co but with ZrC in place of WC, were investigated. Firstly, detailed analysis of both the densification and the shrinkage-rate curves registered during SPS (at 50 MPa) showed that ~1275 °C is the onset SPS temperature for liquid-phase sintering, and ~1600 °C that of full densification. Hardness measurements by Vickers indentation tests confirmed the gradual densification with increasing SPS temperature up to 1600 °C, a condition yielding an extra-coarse-grained (~7–8 μm grain size), ultrahard (~18.2 ± 0.3 GPa) ZrC–Co cemented carbide that is also sufficiently tough (~6.1 ± 0.2 MPa m1/2). And secondly, pin-on-disk tribological tests (at both 20 N for 1000 m and 40 N for 2000 m) and subsequent characterization of the worn surfaces indicated that, under sliding contact, these ZrC–Co cemented carbides wear essentially by two-body abrasion dominated by plastic deformation. Wear increases with increasing severity of the contact conditions, but is nonetheless mild due to the high hardness of these ZrC–Co cemented carbides and to the formation of discontinuous oxide tribolayers.

Establishing a Correlation Between Friction Performance and Tribolayer Formation Using Engineered Mineral Fibers

Abstract This article relates the friction performance to the tribolayer formation when using engineered mineral fibers in the friction formulation. A nonasbestos organic (NAO) nonsteel copper-free passenger car disc pad (PC-DP) nonsteel Cu-free formulation is used to investigate the impact of the fibers on the third body formation and its influence on performance and wear. Full-scale dynamometer performance (AK-Master) test results show the pronounced effect of the fiber length on the friction performance. While a similar overall coefficient of friction (CoF) of around 0.33 is observed in all three cases, more stable friction behavior is observed for the longer fibers, with less variation. This behavior is even more observed in the fade and high-temperature sections. Especially the use of fiber spheres shows quite some unique features over the other tested mineral fibers, especially with respect to pad/disc wear. To understand these differences in performance, the transfer layer and tribolayer on the disc and brake pad are investigated, respectively, by means of scanning electron microscopy (SEM). Formulations showing excellent performance results so far show the formation of a smooth transfer film on the disc. No grooves are visible, and a continuous iron oxide layer is formed at the surface. The tribolayer of the corresponding brake pads nicely shows the formation of a compacted thin layer at the surface. In addition, the importance of mineral fibers in the formulation is highlighted as they are at the core of the tribolayer formation. This study is a step forward toward understanding the role of mineral fibers in a friction formulation and shows its importance toward reducing nonexhaust emissions.

Studies on Adhesive Wear Characteristics of Centrifugally Cast Functionally Graded Ceramic Reinforced Composite

Functionally graded material containing LM13 aluminium alloy as matrix and alumina as reinforcement (10 wt. %) was fabricated (Φout150 × Φin90 × 100 mm) by centrifugal casting. Samples were machined from the cylindrical cast along its longitudinal axis. Variation in hardness along the radial cross-sectional wall revealed 33.7% improvement at the outer periphery due to higher presence of alumina. This zone was preferred for dry sliding wear experiments, designed based on Taguchi L27 orthogonal array by varying the process parameters like sliding velocity, sliding distance and load using pin-on-disc tribometer. Analysis of variance revealed velocity as most influential wear factor, next to load. An optimal condition to minimise adhesive wear was determined at a load of 15 N, sliding velocity of 3.5 m/s and sliding distance of 1250 m. Scanning electron microscope analysis on abraded surfaces showed formation of tribolayer at high velocities and delamination at high loads.

Microstructural, mechanical and tribological performances of carbon fiber reinforced copper/carbon composites

Two kinds of carbon fiber reinforced copper/carbon composites were fabricated for new carbon based pantograph strip via chemical vapor deposition and impregnation/carbonization technologies. Morphology, conductivity, mechanical, tribological performances of the composites were investigated and compared with those of the pure carbon strip used in China’s high-speed railways. Fracture and wear mechanisms were analyzed by probing the failure surface using SEM, 3D profile and physical models. The results reveal that copper mesh-carbon/carbon (C/C) composite and copper foam-C/C composite have more advantages than pure carbon strip in electric conductivity, compact strength and wear resistance. Carbon fiber will bear failure energy and block crack growth during the impact and current-carrying friction tests, thereby improving mechanical strength and wear resistance. Short-cutting carbon fibers with random distribution are not easy to scratch wear surface of friction pair, which is favorable to the formation of a smooth tribolayer for copper foam-C/C composite.

Temperature-induced wear transition in ceramic-metal composites

Wear degradation is a key parameter to evaluate the performance of ceramic-metal composites applied in manufacturing and mining industries. We selected a typical composite (high Mn steel + 50 wt.% TiC) as the model system and studied its wear behavior. The integrity and damage of TiC ceramic particles were analyzed under different temperatures and atmospheres. A critical temperature of ~125 °C at which transitions of wear mechanism occurred was observed for the first time. Below this temperature, hardness dominated the wear behavior as the presence of oxygen induced surface decarburization of ceramic particles with an increased wear rate. The thermodynamics of oxygen-assisted decarburization were investigated using the CALPHAD (CALculation of PHAse Diagram) approach, and the resultant hardness reduction of TiC particles was clarified using density functional theory (DFT) calculations. At temperatures above 125 °C, toughness became the governing factor as the ceramic-metal deformation incompatibility induced fracture of ceramic particles. The formation of nano-crystalline oxide tribolayers improved the fracture toughness of ceramic particles and restrained the wear loss, which was elucidated using DFT calculations. Thus, the current work has delineated the competitive micro-mechanisms consisting of surface decarburization and toughening of ceramic particles, which could be used to interpret the wear behavior of ceramic-metal composites.

High temperature tribological behaviour of PVD coated tool steel and aluminium under dry and lubricated conditions

Aluminium alloys are commonly used as lightweight materials in the automotive industry. This non-ferrous family of metallic alloys offers a high versatility of properties and designs. To reduce weight and improve safety, high strength-to-weight ratio alloys (e.g. 6XXX and 7XXX), are increasingly implemented in vehicles. However, these alloys exhibit low formability and experience considerable springback during cold forming, and are therefore hot formed. During forming, severe adhesion (i.e. galling) of aluminium onto the die surface takes place. This phenomenon has a detrimental effect on the surface properties, geometrical tolerances of the formed parts and maintenance of the dies. The effect of surface engineering as well as lubricant chemistry on galling has not been sufficiently investigated. Diamond-like carbon (DLC) and CrN physical vapour deposition (PVD) coated steel have been studied to reduce aluminium transfer. However, the interaction between lubricants and PVD coatings during hot forming of aluminium alloys is not yet fully understood. The present study thus aims to characterise the high temperature tribological behaviour of selected PVD coatings and lubricants during sliding against aluminium alloy. The objectives are to first select promising lubricant-coating combinations and then to study their tribological response in a high-temperature reciprocating friction and wear tester. Dry and lubricated tests were carried out at 300 °C using a commercial polymer lubricant. Tests using DLC, CrN, CrTiN, and CrAlN coated tool steel were compared to uncoated tool steel reference tests. The initial and worn test specimen surfaces were analysed with a 3-dimensional (3D) optical profiler, scanning electron microscope (SEM) and energy dispersive X-ray spectroscope (EDS) as to understand the wear mechanisms. The results showed formation of tribolayers in the contact zone, reducing both friction and wear. The stability of these layers highly depends on both the coatings’ roughness and chemical affinity towards aluminium. The DLC and CrN coatings combined with the polymer lubricant were the most effective in reducing aluminium transfer.

Flooded drilling of Inconel 718 using graphene incorporating cutting fluid

In order to improve drilling performance of Inconel 718 alloy, a cutting fluid (CF) consisting of 70% water and 30% vegetable oil blended with graphene nanoplatelets was used. Sliding of Inconel 718 workpiece using WC-Co drills with CF containing 54 × 10−5 wt% graphene (GCF) reduced the coefficient of friction (COF) between the tool and workpiece surfaces from 0.16 to 0.08 and resulted in the formation of tribolayers. The maximum drilling torque of 6 Nm for CF was reduced to 2 Nm using GCF. Additionally, arithmetic mean height (Sa) of drilled surfaces decreased from 8 to 4 μm and a reduction in the amount of material transferred from the Inconel 718 to the cutting edge of the drill was observed. The drilling temperature decreased from 150 to 100 °C using GCF during the process. Subsurface plastic deformation that occurred at the drilled surfaces of Inconel 718 was examined by cross-sectional optical microscopy which revealed that both the depth of deformation zone and the magnitude of subsurface strains were lower compared with flooded drilling. Therefore, graphene added in small quantities to the cutting fluid can provide an energy efficient method for drilling of Inconel 718. Graphical abstract

Tribological behavior of friction stir processed SiP/ZA40 in-situ composites

Abstract The effect of friction stir processing (FSP) at different rotation speeds (400, 630, 800, and 1000 r/min) and traverse speeds (25 and 50 mm/min) on the tribological properties of a Si particle reinforced Zn−40Al−2Cu-based in-situ composite was investigated. After preliminary optimization, 800 r/min and 25 mm/min were selected as optimum FSP parameters. According to the results, multi-pass FSP improved the tribological properties. For instance, at an applied pressure of 0.75 MPa, the wear rate and average coefficient of friction (COF) of four-pass FSPed composite were lower than those of base composite by 53% and 50%, respectively. SEM examinations of worn surfaces, wear debris, and worn subsurfaces revealed that the intensive refinement and uniform distribution of microstructural phases, especially the coarse Si particles, reduced Si particles interspacing, and elimination of casting defects were the most important factors enhancing the substrate resistance against sliding-induced deformation. This led to the formation of stable tribolayers that improved the tribological properties.

Influence of two different range of sillimanite particle reinforcement on tribological characteristics of LM30 based composites under elevated temperature conditions

In this work, high temperature wear-resistant LM30/sillimanite composites for automotive applications have been fabricated. Dual particle size composites reinforced with naturally occurring sillimanite mineral were processed and investigated for operating temperatures in the range of 50–300 °C. Sillimanite particles with size range of 1–20 μm (fine) and 75–106 μm (coarse) were mixed in weight ratio of 3:1, 1:1, and 1:3 to be reinforced to the LM30 alloy. SEM micrographs and area mapping/line mapping profile results showed presence of different phases and revealed that sillimanite inclusion changed the morphology of proeutectic silicon to globular and refined its grain size. Particles were well distributed in LM30 matrix. Increase in reinforcement level of particles led to continuous improvement in properties. As such, the best properties were obtained in composite containing 15 wt% sillimanite with proportion of fine: coarse particles as 3:1 (15-DPS3 composite). The transition temperature of wear mode increased from 150 °C for base alloy to 200 °C for composites. For the temperature-pressure condition of 200–1 MPa, 15-DPS3 composite showed 15% higher hardness, 80% lower wear rate, 48% lower friction coefficient, and 28% lower thermal expansion coefficient than base alloy. These wear characteristics of composites were comparable to the commercially used grey cast iron material. XRD of wear track/debris confirmed the formation of tribolayer. SEM analysis of wear track/debris identified the wear mechanisms causing materials loss under different contact pressures. Light-weight and economical composites developed in this research can act as a good substitute for the heavy cast iron components used in industry.

Self-lubrication of tribologically-induced oxidation during dry reciprocating sliding of aged Ti-Ni51.5 at% alloy

The tribological behaviors of Ti-Ni51.5 at% alloy strengthened by finely dispersed Ni4Ti3 particles in reciprocating sliding against GCr15, Al2O3, and ZrO2 at room temperature were studied. Interestingly, the coefficient of friction (COF) suffered a sheer drop (from 0.9 to 0.2) when the aged alloy slid against GCr15 at a frequency of 20 Hz under a 20 N load without lubrication. However, severe-mild wear transition disappeared when a solutionized alloy was used. Moreover, the COF stabilized at a relatively high level when Al2O3 and ZrO2 were used as counterparts, although their wear mechanisms showed signs of oxidation. Scanning electron microscopy (SEM) and X-ray element mappings of the wear scars of the counterparts clearly indicate that the formation of well-distributed tribo-layer and material transfer between the ball and disk are pivotal to the severe-to-mild wear transition in the aged Ti-Ni51.5 at% alloy/GCr15 friction pair. The higher microhardness and superelasticity of the aged alloy significantly accelerate the material transfer from GCr15 to the disk, forming a glazed protective tribo-layer containing Fe-rich oxides.

Fretting wear evolution of γ-TiAl alloy

Fretting wear evolution of γ-TiAl alloy was investigated. Evolution of wear scar, tribolayer and wear debris were studied using optical microscope and scanning electron microscope. The results show that the wear debris generated from γ-TiAl alloy can be compacted to form a tribolayer rapidly after 100 fretting cycles. At the starting stage, the rapid formation and rupture of tribolayer alternatively occur due to insufficient thickness of the tribolayer. With the proceeding of fretting, the thickness of tribolayer increases due to increase in the amount of the wear debris, which makes the tribolayer more stable. The evolution of the wear debris and the formation of tribolayer significantly influence the fretting wear behavior of γ-TiAl alloy. The wear rate of γ-TiAl alloy decreases rapidly from 255.6 × 10−3μm3 /(N·μm) after 2000 fretting cycles to 35.5 × 10−3μm3 /(N·μm) after 10,000 fretting cycles when a thick tribolayer is formed. A physical model was proposed to describe the evolution process of the fretting wear of γ-TiAl alloy.

Tribological behavior of oils additised with a phosphonium-derived ionic liquid compared to a commercial oil

PurposeThe purpose of this paper is to study the antifriction, antiwear and tribolayer formation properties of the trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate ionic liquid (IL) as additive at 1 wt.% in two base oils and their mixtures, comparing the results with those of a commercial oil.Design/methodology/approachThe mixture of the base oils used in the formulation of the commercial oil SAE 0W20 plus the IL was tested under rolling/sliding and reciprocating conditions to determine the so-called Stribeck curve, the tribolayer formation and the antifriction and antiwear behaviors.FindingsThe use of this IL as additive in these oils does not change their viscosity; improves the antifriction and antiwear properties of the base oils, making equal or outperforming these properties of the SAE 0W20; and the thickness and formation rate of the tribolayer resulting from the IL-surface interaction is highly dependent on the type of base oil and influence on the friction and wear results.Originality/valueThe use of this IL allows to replace partial or totally commercial antifriction and antiwear additives.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2020-0179/