Severe Wear Conditions Research Articles

Predictive modeling of abrasive wear in in-situ TiC reinforced ZA37 alloy: A machine learning approach

Abrasive wear rates are of significant interest in various industrial applications where materials are subjected to severe wear conditions. The study analyzed high-stress abrasive wear rates on the novel in-situ TiC reinforced ZA37 composites. The inclusion of in-situ TiC reinforcement in ZA37 alloy has shown potential for enhancing wear resistance. The impact of tribological test parameters on the abrasive wear response was analyzed using response surface methodology (RSM). Using tribological data, various machine-learning algorithms were trained to predict the wear behaviours of the developed composites. The performance measurements show that the machine learning models accurately predicted the abrasive wear response of test samples. Our findings suggest that machine learning can revolutionize tribology, paving the way for tribo-informatics.

Effect of Cr3C2 on wear behavior of Ni45 laser cladding coating

Abstract To improve the performance of engineering components subjected to severe wear, temperature fluctuations, and corrosive conditions in industries such as chemical, aerospace, and power plants, Ni45-based coatings with varying Cr3C2 contents (0%, 10%, 20%, and 30%) were applied to a 45-steel surface. The microstructure of these coatings was examined by scanning electron microscopy (SEM), and their wear resistance was compared. As the Cr3C2 content in the cladding layer increased, there was a notable improvement in its wear resistance. Specifically, when the Cr3C2 content reached 30% by weight, the wear resistance of the cladding layer exceeded that of the GCr15 steel. Furthermore, the adhesive wear between the cladding layer and the GCr15 steel diminished, while the oxidation wear of the GCr15 steel intensified. This study aims to elucidate the primary wear mechanisms of the Cr3C2/Ni45 cladding layer and offer valuable insight into improving the durability of engineering components in harsh environments.

Volumetric efficiency degradation prediction of axial piston pump based on friction and wear test

The axial piston pump (APP) is being developed towards higher pressure and higher rotational speeds to enhance operational power density. The piston-cylinder friction pair is a critical component of the APP. Due to its lack of self-compensation capability, the leakage of the piston-cylinder friction pair escalates rapidly under increasingly severe wear conditions. An innovative method for predicting the performance degradation and lifespan of APPs based on friction and wear tests has been proposed. This method can effectively predict the performance degradation trends of APPs under different operating conditions. The actual contact force on the piston pair (PP) during operation is determined through dynamic analysis. Friction and wear tests were conducted on 38CrMoAl piston and ZCuPb15Sn8 cylinder materials under various conditions using a testing apparatus. Utilizing friction and wear theory, the volumetric efficiency of APP under various operating conditions was derived as a function of operational time. The reliability of the theoretical analysis was validated through leakage tests on the APP. The results indicate that volumetric efficiency decreases exponentially with increasing working pressure at rated speed. This research provides theoretical guidance and an experimental foundation for the failure prediction of volumetric efficiency degradation in APP.

Effects of Ti addition and wall thickness on microstructure, hardness, and wear properties of spheroidal graphite cast irons

Spheroidal graphite cast irons (SGCIs) have been commonly used in automotive and energy sectors where superior mechanical strength and wear resistance are required. This paper investigated the performance of the SGCIs under severe wear conditions as a function of Ti content and cooling rate. SGCIs alloyed with various Ti content (0, 0.1, 0.2, 0.3, and 0.5 wt%) were produced by green sand-casting process in different section sizes (10, 30, and 50 mm). Ball-on-disk type wear equipment with an Al2O3 ball was used to determine the wear rates of the SGCI samples. With increasing Ti content, up to 45% of nodular graphite turned into vermicular graphite, depending on the Ti addition and section sizes. Carbide precipitation was observed in the matrix due to the carbide-forming effect of Ti. The hardness and wear resistance of the SGCIs were improved by adding Ti owing to the combined effects of increasing pearlite and TiC particles precipitated in the matrix. Thinner-wall castings provided a faster cooling rate, which improved hardness and wear resistance. Alloying with 0.5 wt% Ti decreased the wear rates up to 35%.

Microstructural evolution and performance analysis of WC-11Co reinforced iron matrix composites

This paper presents a new fabrication method utilizing lost foam casting as a processing technique to synthesize high-strength and ultra-wear-resistant particle reinforced iron matrix composites. The composite material incorporates large-sized WC-11Co reinforcement. The composite exhibits a multiphase microstructure composed of WC-11Co, α-Fe, and carbide precipitates that extend at different length scales. The precipitation of large-sized M3W3C (M = Fe, Co) type carbides at the WC-11Co/matrix interface is well controlled. A favorable reaction layer is formed between WC-11Co and the matrix. Nano-precipitates are pinned within the reaction layer, exhibiting a high degree of coherence with the iron matrix. The stress field at the interface is complex due to thermal stress, phase transformation stress, and microstress. The stress state between WC-11Co and the matrix consists of compressive residual stress-tensile residual stress-compressive residual stress, with compressive residual stress far exceeding tensile residual stress. The WC-11Co/Fe0.35C5CrMn composite exhibits outstanding compressive strength of 2.18 GPa and a fracture strain of approximately 24.6 %. Moreover, the composite demonstrates excellent wear resistance, with a threefold improvement compared to the matrix under severe wear conditions. The following mechanisms contribute to the enhanced mechanical properties: multiphase material system, coherent multiscale interfaces, grain refinement, dislocation strengthening, and residual stress strengthening.

Enhanced Microstructure and Wear Resistance of Ti-6Al-4V Alloy with Vanadium Carbide Coating via Directed Energy Deposition.

Ti-6Al-4V alloys are known for their suboptimal tribological properties and are often challenged by durability issues under severe wear conditions. This study was conducted to enhance the alloy's wear resistance by forming a hardened surface layer. Utilizing directed energy deposition (DED) additive manufacturing with a diode laser, vanadium carbide particles were successfully integrated onto a Ti-6Al-4V substrate. This approach deviates from traditional surface enhancement techniques like surface hardening and cladding, as it employs DED additive manufacturing under parameters akin to those used in standard Ti-6Al-4V production. The formed vanadium carbide layer achieved a remarkable thickness of over 400 µm and a Vickers hardness surpassing 1500 HV. Pin-on-disk test results further corroborated the enhanced surface wear properties of the Ti-6Al-4V alloy following the additive-manufacturing process. These findings suggest that employing vanadium carbide additive manufacturing, under conditions similar to the conventional DED process with a diode laser, significantly improves the surface wear properties of Ti-6Al-4V in metal 3D-printing applications.

The properties of laser-clad coatings made of NiCrBSi alloy and recycled tungsten carbides

Tungsten carbide hard metals are one of the most known and successful powder metallurgical products used in environments where severe wear conditions prevail. Since tungsten belongs to the list of critical raw materials for the European Union (EU), its recycling is highly desirable. In this paper, recycled tungsten carbide powders fabricated by the zinc-reclaim process where mixed with NiCrBSi matrix and deposited with one-step laser cladding using a coaxial powder feeding on mild steel substrates. Prepared clads were tested in low-stress rubber wheel abrasion tests and compared with clads produced from commercial macrocrystalline (WC) and cast and crushed eutectoid WC/W2C reinforced clads. The results showed that recycled WC induced porosity in clads when produced with ‘production’ laser cladding parameters due to small carbide size resulting in poor wear performance. When laser-clad with lower heat input and productivity, pore-free clads with excellent wear performance were obtained.

Effect of carbon content on structure and properties of (CuNiTiNbCr)CxNy high-entropy alloy films

High-entropy alloy films have shown excellent mechanical performance, but their hardness and wear resistance are still lower than those of conventional hard films such as TiN and CrN, which cannot meet the requirements of hard film applied under severe wear conditions. In this study, the (CuNiTiNbCr)CxNy high-entropy nanocomposite films were prepared by the double-target co-sputtering method. The effect of carbon content on the film morphology, phase structure, mechanical properties and tribological properties were investigated. With the introduction of carbon atoms in the film, the amorphous/carbonitride/amorphous carbon composite structure is formed. At 21.5 at.% carbon, the film hardness reaches the highest of 18.1 GPa. And at 37.6 at.% carbon, the film shows the highest toughness of 0.96 MPa m1/2 and exhibits the best tribological properties with a low friction coefficient of 0.27 and a wear rate of 1.0 × 10−6 mm3/N·m. The improvement in wear resistance is mainly attributed to the strong toughness of nanocomposite structures and the lubrication effect of amorphous carbon phase. The (CuNiTiNbCr)CxNy high-entropy nanocomposite films show good application prospect in harsh friction environments.

Comprehensive study of process parameters and their effect on tribological properties of laser cladded Ti6Al4V alloy: A review

Titanium alloy (Ti6Al4V) is quite a very versatile material due to its high specific strength and the ability to resist corrosion but its usage is restricted in severe wear condition due to its poor tribological properties. Thus, in order to enhance its application, it must be subjected to surface modification techniques. Surface modification consist of the broad range of processes designed to improve the surface properties of different classes of material (ferrous and non-ferrous). Laser coating process is one of such technology which enables the investigator to modify the surface property of metallic base material. Laser coating process provides less dilution and fusion bonded metallic coatings on variety of metallic materials with minimum heat input. Here, this review article presents a study on the various laser process parameter such as travel speed, laser power, coating powders feed rate, composition etc., and their effects on the tribological properties of laser cladded Ti6Al4V (grade5) such as microhardness, wear rate and coefficient of friction (COF) etc. In addition, the effects on different properties such as corrosion resistance, affinity for oxygen and adhesion strength of Ti6Al4V are also reviewed.

A Hydraulic Axial Piston Pump Fault Diagnosis Based on Instantaneous Angular Speed under Non-Stationary Conditions

Due to the intense noise interference in hydraulic systems, it is extremely difficult to detect component faults through vibration signals. Diagnostic performance is also constrained by highly time-varying and non-stationary operating conditions. This study proposes to use instantaneous angular speed (IAS) signals that are both operational and state parameters as sources of information. Firstly, the instantaneous angular speed fluctuation (IASF) of a piston pump is analyzed theoretically, and it is concluded that its fluctuating components contain the health status information of the components. The IASF can then be obtained by subtracting the speed trend term from IAS signals obtained via a magneto-electric speed sensor. A synchro-extraction of the normal S transform (SNST) is proposed to process it via line-pass filtering. Finally, the filtered and reconstructed IASF signal is utilized to draw a two-dimensional polar coordinate map online. A non-stationary-condition test is carried out on the test platform to monitor the morphological characteristics of the valve plate under normal, slight, and severe wear conditions. The polar plot shows significant increases in speed fluctuations and oscillation times within a range from 180° to 270°. The relevant research results reflect that the IAS signal can provide a new method for monitoring the operating status of and conducting fault diagnoses for hydraulic equipment.

Effects of B/C ratio on the structural and mechanical properties of TiBCN coating deposited by PACVD

TiBCN coating is known as a hard, self-lubricant and wear resistant coating which can be applied on industrial tools to increase their working life time under severe wear conditions. In this paper, TiBCN coatings with different B/C ratios were applied on H13 steel using plasma-assisted chemical vapor deposition from BBr3, TiCl4, CH4, N2 and H2 reactants at 500 °C. The results signified that the introduction of B and C elements to TiN changed its preferred crystalline orientation from (200) to (111) and decreased crystal size from 12 to 9 nm as a result of the formation of amorphous phases which constrain grain growth. The addition of B and C altered the coating's nucleation and growth mechanisms and generated a strong surface etching agent of HBr which significantly changed surface morphology and roughness. Increasing flow ratio of CH4 to BBr3 from 0.125 to 0.25 influenced the coating's mechanical properties and increased coating's hardness from 18.1 to 23.2 GPa and Young's modulus from 296 to 334.7 GPa. Rising coating's C content remarkably improved its nano-wear resistance and the coating with the highest C content exhibited a wear volume of 1*10−19 m3 which was about 63% lower than that of TiN coating.

Wear of Tailored Forming Steels

This study investigates the wear behavior of additively welded cladding layers on less wear‐resistant base materials using plasma‐transferred arc welding and laser hot‐wire cladding. The cladding layers are made from atomized AISI 52100, AISI 5140, and a stainless steel with (0.52 wt% C, 0.9 wt% Si, 14 wt% Cr, 0.4 wt% Mo, 1.8 wt% Ni, 1.2 wt% V, bal. Fe) on unalloyed steel AISI 1022M as the base material. The specimens' microstructure and surface hardness are comparable with conventional specimens of monolithic AISI 52100 and AISI 4140, which is used as a reference. Tribometer tests are carried out in ball‐on‐disk configuration to investigate the wear resistance of the specimen. The multimaterial specimens show comparable wear behavior to their monolithic counterparts, and a good performance of the stainless specimen in pure sliding is proven. These findings suggest that additive manufacturing processes can be used to clad less wear‐resistant base materials and achieve high wear resistance, making it possible to exploit the advantages of surface coatings under severe wear conditions.

Tribological behaviour and wear mechanism of ADI with different hardness values

The tribological behaviour and wear mechanism of austempered ductile iron (ADI) with different hardness values were investigated. Results showed that the wear resistance of ADI was sensitive to hardness and service conditions. Under mild wear conditions, the low-hardness ADI sample exhibited high wear resistance because graphite was easy to transfer to the tribosurface and acted as a lubricant to reduce the friction coefficient. However, the high-hardness ADI sample was hard to deform plastically, which restricted the transfer of graphite from the matrix to the tribosurface. Under severe wear conditions, the plastic deformation of the low-hardness ADI sample gave rise to abrasive wear, which resulted in poor wear resistance. With the deterioration of wear conditions, the wear mechanism of ADI was transformed from micro-cutting wear to oxidative wear.

Elastic properties of the non-mixing copper donor assisted material in friction stir welding of aluminum alloys using nanoindentation

Friction stir welding of high-strength materials such as steels is the impeded by the lack of the vast heat input needed to start the process. Contact friction is considered the most dominant source of heat generation for FSW steels which tends to cause severe wear conditions of the tool hear. To relieve the extreme wear conditions that occur on the tool heads because of FSW steels, we introduce the non-mixing Cu donor stir material to friction stir welding of aluminum alloys. The elastic properties of the Cu donor assisted friction stir welded aluminum alloys are measured using nanoindentation. The hardness and elastic modulus were measured for two regions, the base metal (BM) and the stir zone (SZ). The measurements were conducted for 20% and 60% Cu non-heat treated (NHT) and heat-treated (HT) samples. The nanomechanical properties were measured using nanoindentation with the continuous stiffness method (CSM) in depth control. The HT samples are softer than the NHT samples as expected. However, the 20% Cu NHT and HT samples depicted the same hardness at the SZ. Similar results were observed for the 60% Cu donor stir samples. It therefore concluded that the SZ is softer than the BM for the 20% and 60% Cu donor stir material as expected. The hardness of the weld at the SZ is similar to the hardness of the Al6061-T6 plate, suggesting that the Cu donor stir material did not impact the hardness properties of the Al6061-T6 plate due to the depletion of the Cu donor stir material during the welding process, an important result of the concept of the donor material. The elastic moduli of the Cu donor stir welded samples vary between 75~85 GPa at a depth of indentation of ~4600 nm, which are different from the elastic moduli of Cu 110 (117.2 GPa) and similar to the elastic modulus of aluminum alloys (68.9 GPa), an important outcome.

Microstructure and wear resistance of laser cladding Ti-Al-Ni-Si composite coatings

To enhance the tribological performance and avoid the surface failure of TC4 alloys under severe wear conditions, Ti-30Al-16Ni-3Si, Ti-48Al-3Si, and Ti-50Al (at. %) coatings were fabricated on TC4 substrate by laser cladding. The coatings' composition, microstructure, microhardness, and wear resistance were investigated through XRD, SEM, TEM, and performance testing methods. The phase constituents in the Ti-50Al coating were TiAl and Ti3Al, while Ti5Si3 and Ti5Si3-TiAl eutectic structure formed in the Ti-48Al-3Si coating. The phase constituents in the Ti-30Al-16Ni-3Si layer were the matrix phases of Ti2Ni and Ti3Al and the reinforcement of Ti5Si3. Meanwhile, Ti2Ni-Ti3Al eutectic structure and Ti5Si3-Ti2Ni eutectic structure were also formed. Ti-30Al-16Ni-3Si coating exhibited a higher microhardness and wear resistance, attributed to the interphase distribution of Ti3Al phase and Ti2Ni phase, and the tight combination of Ti3Al-Ti2Ni eutectic structure, which imparted the coating a higher strength and toughness. Compared with the TC4 substrate, the microhardness of the Ti-30Al-16Ni-3Si coating was increased by 2.5 times, and the wear volume loss was reduced by 37 %. The wear mechanism of Ti-50Al coating and Ti-48Al-3Si coating were abrasive wear and adhesive wear, while Ti-30Al-16Ni-3Si coating was mainly adhesive wear.

Recent advancements in nanocomposite coating manufactured by laser cladding and alloying Technique: A critical review

This review article discusses about the development of nanocomposite coating on surfaces of metallic materials produced by laser surface cladding and alloying process. The purpose of coating is to deposit hard, wear and corrosion resistant layer on the surface of metallic material so that the materials can be used for manufacturing of engineering components operated in severe wear and corrosion environment. Nanocomposite coatings are having wide applications in automobile, chemical, aerospace and electronics industries due to its attractive properties like very high hardness, good tribological properties, excellent corrosion resistance and excellent oxidation resistance at high temperature. The various engineering materials upon which nanocomposite coatings can be fabricated are ferrous materials, aluminium alloy, titanium alloy, nickel based super alloy and magnesium alloy. The laser surface cladding and alloying process are widely used for fabrication of nanocomposite coating on metallic materials because of its excellent characteristics such as fast solidification and cooling rate, production of fine microstructure, highly flexible process, less dilution, narrow heat affected zone and highly automated process. The nanocomposite coating can be formed by transition metals, alloys, ceramics, and rare earth oxides. The formation of nanocomposite coating depends upon the laser process parameters and selection of nanoparticles during coating process. The various laser process parameters which control the formation of nanocomposite coating are laser power density, laser scanning speed, argon flow rate, feed rate of powder, wavelength of laser beam, frequency of laser, and laser spot diameter. The nanocomposite coated metallic materials can be used for manufacturing of mechanical components like turbine blades, friction devices and automobile parts applicable to severe wear and corrosive conditions. In this review paper the problem arises during laser processing for nanocomposite coating formation on various metallic materials and its control has been described.

Accelerated tribological testing based life prediction of aluminium-graphite tribo composite

Electrical sliding contacts in electrical motors and generators are subjected to severe friction and wear conditions. Conventional materials such as carbon and electrographite do not have longer life due to the generation of carbon dust. This creates environmental pollution and also affects the operation of an electrical machine. Aluminium-graphite composites are well suited for such applications. However, the life of the components made out of aluminum-graphite composite is to be evaluated in order to optimize their performance at the design stage itself. Traditional life data analysis at normal usage conditions is time-consuming. In the present study, aluminum-graphite composites were manufactured through the energy-efficient microwave sintering, and the life of components was estimated using Accelerated Life Testing (ALT) procedure. The experimental wear data were analyzed using an inverse power law model. Reliability and failure rate models were developed using the time-to-failure data. Life at normal usage conditions was predicted using these models. The calculated reliability at normal usage conditions was more than five years at a 99% confidence limit.

Microstructure and hardness evaluation of Stellite 6 coating developed on hot forging die steel using gas tungsten arc cladding process

Hot forging die steels are subjected to severe wear conditions aggregated by severe pressure, high friction and high temperature. These conditions directly affect the die life. Refabrication of dies and improvement of die life can be accomplished by developing a hard coating on the die surface. Cobalt based alloy Stellite6 has excellent wear and corrosion resistant properties and can retain its hardness at high temperature. The retained hardness at elevated temperature is due to carbides dispersion in Co-Cr matrix. In the present study, gas tungsten arc cladding (GTAC) process is used to deposit Stellite6 powder on die steel (56NiCrMoV7). GTAC process has benefits like lower heat input, better weld bead control, low distortion, low gas absorption and low cracking tendency. This study deals with the evaluation of hardness, microstructure and cracking tendency of the deposited cladding layer. Claddings are developed with four different heat inputs by changing the current (55, 65, 75 and 85A) at constant scan speed. It has been observed that at 55A current the heat input is not sufficient to melt the powder and deposit on the surface, whereas at 85A current, small clad layer is developed. It has also been observed that except cladding developed at 85A current; other claddings are cracked just below the cladding layer and the samples are distorted due to the thermal stresses developed during cladding process. This emphasis that pre-heating and post-heating are required for GTAC process. The micro-hardness of clad layer and dilution layer is about 430 ± 10 HV0.5, whereas heat affected zone and base material are 750 HV0.5 and 390 ± 10 HV0.5 respectively. The combined height of the clad zone and dilution zone ranges from 1.237 to 2.489 mm.

Relationship between flash temperature and wear characteristics in Ni-nano Al2O3 coating

Ni-nano Al2O3 composite coatings were deposited on soft Al6061 substrate material. The microstructures of the thin coatings, adhesive strength, hardness, and tribological behavior were studied. The increase in specific wear rate was observed with an increase in the load applied on the pin. This has also resulted in an increase in the flash temperature. This is attributed to the ploughing effect caused by the increase in the uneven surface contact. The study demonstrates that even under extreme loading conditions the Ni-nano Al2O3 composite coating exhibits higher wear resistance. This favors the application of the composite coatings at severe wear conditions.

Effects of Y2O3 addition on the microstructure and wear-resistant performance of TiN/TiB-reinforced Ti-based laser-clad coatings on Ti‐6Al‐4V alloys

To enhance the wear resistance and further extend the application of Ti alloys under severe wear conditions, TiN- and TiB-reinforced Ti-based composite coatings modified with Y2O3 were fabricated on Ti‐6Al‐4V alloys by laser cladding. The effects of Y2O3 addition on the phase constituents, microstructural characteristics, microhardness, and tribological properties of the coatings were investigated. The phase constituents in the coatings were TiN, TiB, and α-Ti, and remained unchanged after adding Y2O3. The addition of Y2O3 weakened the side-branching tendency of TiN and promoted the morphological conversion of TiB from needles to plates by modifying the local constituents and temperature in the melt pool. With an increase in the Y2O3 content, the microhardness and wear resistance of the coatings first increased and then decreased, which was consistent with the compactness of the microstructure. The superior tribological properties of the coatings were attributed to the increased load-bearing provided by the large-sized TiN and TiB units and the increased load-transfer strength induced by the fine TiB whiskers. The coating fabricated with 1 wt% Y2O3 exhibited the highest microhardness and lowest wear loss, and the wear mechanism it underwent was abrasive wear characterized by micro-cutting. This study demonstrates the possibility of modifying the microstructures of Ti-based composite coatings with Y2O3.