Papers by Keyword: Wear Resistance

Abstract: The objective of this study is to investigate the tribological properties of detonation-sprayed (Ti,Cr)C-Ni coatings under dry and lubricating conditions. The (Ti,Cr)C-based coatings with 25 wt.%, and 33 wt.% of Ni binder were applied onto steel substrates by detonation spraying. Microreciprocating wear tests were performed under dry and lubricating conditions with water, diesel, biofuel, aviation fuel and oil as a lubricating environment. Post-test examination of wear tracks was performed using interference profilometry and SEM analysis. The (Ti,Cr)C-Ni detonation-sprayed coatings exhibit a dense microstructure, featuring well-bonded splats composed of fine (Ti,Cr)C particles and Ni-based binder. The lowest wear rates of the (Ti,Cr)C-25wt.%Ni and (Ti,Cr)C-33wt.%Ni coatings are observed in an oil environment. Instead, the wear rates of both coatings are highest in a water environment. The (Ti,Cr)C-25%wt.Ni detonation-sprayed coating is characterized by an increased wear rate in the water environment as compared with (Ti,Cr)C-33%wt.Ni due to more intensive brittle failure in the water environment.

Abstract: This study presents a novel approach to optimizing energy consumption in rock destruction by integrating advanced design parameters of cutting elements. A hybrid experimental-computational model was developed to evaluate the specific energy of destruction () across granite, limestone, and sandstone. Key findings include energy savings of 15% in granite, 12.5% in limestone, and 13.7% in sandstone, achieved by optimizing the angle of attack – 30º, edge curvature – 0.5 mm, and applying wear-resistant DLC coatings 2500 HV. Laboratory tests, field experiments, and finite element simulations validated the model's accuracy within ±6%. The study identifies critical parameter interactions, such as angle of attack and coating hardness, reducing shear stresses and wear losses. These advancements lower operational costs by approximately $50,000 annually per excavator and extend tool life. Limitations include the limited range of rock types tested and slight simulation overestimations in abrasive sandstone. Future research should explore adaptive cutting element designs with real-time parameter adjustments using sensor-based systems and machine learning. The findings offer practical recommendations for implementing optimized tools in mining and construction, enhancing efficiency and cost-effectiveness. This work bridges theoretical insights and industrial applications, providing a scalable framework for energy-efficient rock destruction.

Abstract: This comprehensive review paper provides an in-depth analysis of the tribo-corrosion behaviour and wear resistance of biomedical materials, focusing on their application in orthopaedic and dental implant settings. Various materials such as titanium alloys, stainless steel, CoCrMo alloy, UHMWPE, and Ti-based alloys are examined for their mechanical, tribological, and corrosion properties. The impact of surface modifications, coatings, and manufacturing techniques on the performance of these materials is thoroughly explored. Experimental investigations and characterization techniques including SEM analysis, X-ray diffraction, nanoindentation, and electrochemical impedance spectroscopy are utilized to assess tribo-corrosion behaviour, wear resistance, and mechanical properties. The significance of specific parameters such as coating thickness, temperature, sliding speed, and load in determining the performance of biomedical materials is highlighted. The review emphasizes the need for continued research and development to enhance the tribological properties of biomedical metallic materials, with promising implications for orthopaedic implant longevity and human health. Keywords: Tribo-corrosion, Wear Resistance, Biomedical Materials, coatings, Pin-on Disc

Abstract: This study investigates the effectiveness of carbon nanotubes (CNTs) in enhancing the surface hardness of mild steel through carburization. CNTs were synthesized via chemical vapor deposition at 700°C using iron nitrate and cobalt nitrate as precursors on CaCO₃ support. Acetylene was used as the carbon source and nitrogen as the inert gas. The as-synthesized CNTs were purified using a one-step nitric acid treatment. Characterization by SEM, TGA, and FTIR revealed CNT diameters of 42-52 nm and improved thermal stability after purification, with TGA showing mass losses of 78% for as-synthesized CNTs and 85% for purified CNTs. Low carbon steel (AISI 1018) samples were carburized with as-synthesized and purified CNTs at austenitic temperatures of 750°C and 800°C for period ranging from 10 to 50 minutes. The carburizing process involved heating at 10°C/minute, followed by a defined number of boost and diffusion steps. Surface hardness was evaluated using a Vickers FM 700 micro-hardness tester, and microstructure was checked with an Olympus SC50 optical microscope. Results show that the use of purified CNTs in the carburization displayed the highest surface hardness of 191.64 ± 4.16 GPa at 800°C for 50 minutes, representing a 32% increase over the untreated substrate (145.188 ± 2.66 GPa). As-synthesized CNTs yielded a hardness value of 177.88 ± 2.35 GPa under the same conditions. At 750°C, the percentage increase in hardness for as-synthesized CNTs and purified CNTs were 10.04% and 15.77%, respectively, compared to the untreated substrate. Higher carburization temperature and longer treatment time consistently increased the surface hardness. The use of purified CNTs resulted in an increase of 6.37% hardness when compared to that of the as-synthesized CNTs at 750°C. Microstructural changes in the steel samples confirmed improved surface hardness with both purified and unpurified CNTs, with purified CNTs showing superior performance. This study therefore provides a platform for the use of CNTs for enhancing surface hardness of steel for various industrial applications requiring enhanced mechanical properties and wear resistance in low carbon steels.

Abstract: This study examines the wear behavior of Ti6Al4V following nanosecond pulse laser surface texturing (LST) using 15 W power, 60 kHz frequency, and 180 mm/s speed. Tested under dry sliding conditions with a 20 N load, 0.3 m/s speed, and 900 s duration, LST produced melt bulges that enhanced surface wear resistance. This study demonstrates that nanosecond pulse laser surface texturing on Ti6Al4V significantly enhances wear resistance, reducing wear rate by 3% and coefficient of friction by 5%.

Abstract: In this article, the effect of TiC nanopowder particles on the wear resistance of low-alloy steel 35XGCL (analog is JIS G 5111) is mathematically modeled. First of all, the composition for liquefaction in an electric arc furnace was calculated. 5 and 10% TiC nanopowder particles were added to the alloy as a modifier before pouring liquid metal into the ladle. This process was performed before pouring the liquid metal from the furnace into the ladle. 15% of TiC was added in the furnace as a modifier. Lagrangian interpolation polynomial construction was used in this modeling. The amount of wear resistance was calculated by polynomial expression of the function with determination of unknown coefficients. The results obtained on the basis of the developed model were compared with case studies. The results of the analysis are shown by graphs.

Abstract: The tool steel materials are expensive this is the reason why the lifetime increase is a goal of the production technology. The tool life is determined by the various complex mechanical, thermal, chemical, and tribological properties. Tools properties depend on the chemical composition and their microstructure. The microstructure depends on the chemical composition, the production process, the heat treatment and surface treatment technologies. The goal of this research was to increase the service lifetime of the casting mould tool. It was prepared and investigated four kinds of test specimens. The first kind of specimen was made from conventional steel (W302). It was made an austenitization (1020°C) and was cooled with 9 bar nitrogen gas to 40°C and kept for 6 minutes. The quenching was followed with three times tempering processes (570°C, 580°C, 560°C) in 2 bar N₂ gas. The second kind of test specimen was made from Unimax electro-slag remelted steel (ESR). It was made an austenitization (1020°C) and was cooled with 9 bar nitrogen gas to 40°C and kept for 6 minutes. After quenching the process continues with three times tempering (610°C, 620°C, 600°C). The third kind of test specimen Unimax a electro-slag remelted steel (ESR), to which firstly an austenitization (1020°C) was made, quenched in nitrogen gas with 9bar and then cooled in liquid nitrogen till minus 150°C. After cryogenic treatment, the process continues with three times tempering (610°C, 620°C, 600°C). The fourth kind of specimen was made by the same process as the second and after it a PVD coating process was made to coat the surface by a TiBN layer. It investigated the hardness and wear resistance of all heat-treated and surface-coated steel specimens. The comparative wear resistance testing was investigated by a ball cratering tester. The rank of the tested specimen was the next: the lowest wear resistance measured in the case of the heat-treated W302, the middle in the case of cryogenic heat-treated Unimax and the highest wear resistance earned in the case of the PVD-coated Unimax. The results of the investigations proved that the Unimax tool steel service lifetime can increase better than the conventional tool steel by heat treatment and surface treatment. The practice certified that the surface-treated Unimax tools' service lifetime is much longer than the conventional ones.

Abstract: The paper presents experimental investigations of the adhesive properties of meta-aramid coatings applied to metal substrates of different types. The increased adhesion ability of meta-aramid coatings to copper substrates was found in comparison with other metals and alloys used as structural materials. The dependence of the strength of the adhesive bond of the meta-aramid coating on the surface roughness at various concentrations of the polymer solution has been determined.

Abstract: The main purpose of this investigation was to study the effect of strain hardening on wear properties of 316 austenitic stainless steel (ASS). Cold deformation was performed by using a universal tensile machine for 20% CW and 40% CW followed by heat treatment to relieve internal stresses. A secondary cold working process was performed for the heat-treated samples followed by a secondary heat treatment. Wear test measurements and microscopic examinations were preformed for all samples. It was observed that by increasing the strain hardening percentage the hard brittle martensite phase increases. Also, by increasing both the SiC grit of the emery papers (which was used in the wear test) and the time of the wear test, the weight lost per unit area was decreased. The wear resistance was increased by using single and double 20% strain hardening but by exceeding the cold working to more than 40% the wear resistance decreased.

Abstract: Nanotitania is a well-acceptable material in biomedical applications due to its excellent biocompatibility. However, its other performances in terms of physical properties, mechanical properties and specific wear rate have been the keen interest of researchers. The study aims to modify dental composite formulation by adding nanotitania filler in different mass fractions and study to investigate its influence on physical and mechanical properties. A conventional monomer matrix consisting of Bisphenol A-Glycidyl methacrylate (BisGMA), Urethane dimethacrylate (UDMA), Triethylene glycol dimethacrylate (TEGDMA), Camphor Quinone (CO), Ethyl-4-dimethylaminobenzoate (EDMAB) was first added and modified with varying nanotitania filler fractions (0,0.5,1,1.5 wt. %). The performance of newly formulated composites was investigated in four major parameters like apparent porosity, hardness, compressive strength and specific wear rate. All tests are performed as per ISO4049 standard which are requirements for fabrication, characterization, direct/indirect restoration of dental composite, inlays, onlays, veneers, crowns and bridges. Specific wear rate was estimated using pin on disk tribometer under constant load of 20N. Due to its extremely hard and brittle nature, the micro-hardness and compressive strength of resin composite on adding 0.5 wt.-% of nanotitania filler fraction (DC0.5TiO₂) were increased by 68% and 16% respectively. Using a pin on disc tribometer, a wear assessment has been performed and it was found that under constant wear parameters and distilled water environmental conditions, the specific wear rate was decreased by 26 % on adding 0.5 wt.-% mass fraction of nanotitania. Nanotitania indicated excellent performance based on mechanical and wear properties and hence, it can be suggested to use nanotitania as a novel filler of dental composite for the replacement of other non-biocompatible ceramic filler.