Rubber Wheel Test Research Articles

The effects of heat treatment on the mechanical properties of 450 HB wear resistant steel

The effects of heat treatment on the mechanical properties of 450 HB wear resistant steel produced by Usiminas steelworks in the form of heavy plates were investigated. The results showed that when tempering temperature is lower than 200°C, there are no significant changes in hardness, tensile properties and absorbed energy in Charpy V-notch test. With further increase in temperature up to 400°C, hardness, tensile strength, total elongation and impact toughness exhibited a slight downward trend. For heating carried out from 400°C to 600°C, a very significant drop in hardness and tensile strength and an increase in total elongation and absorbed energy values were observed. The abrasive wear resistance, evaluated by dry-sand rubber wheel test, increased with the heating up to 500°C. With the additional rise in temperature to 600°C, the abrasive wear resistance decreased, reaching a similar level to the reference state (steel in as-delivered condition).

Abrasive Wear Properties of Wear-Resistant Coating on Bucket Teeth Assessed Using a Dry Sand Rubber Wheel Tester.

Ni60-WC coatings with different WC contents on the bucket tooth substrates were pre- pared using laser cladding technology. Their abrasive wear properties were assessed using the dry sand rubber wheel test system. The substrate and the hard-facing layer were tested for comparison. The results showed that the hardness of the Ni60-WC coatings increased with the increase in WC content. The wear resistance of the bucket tooth substrate was greatly improved by hard-facing and laser cladding Ni60-WC coatings. The wear rate of the hard-facing layer was reduced to 1/6 of that of the tooth substrate. The wear rate of the laser cladding coatings with 20-40 wt.% WC was similar to that of the hard-facing layer. It is worth mentioning that the wear rate of the coatings with 60-80 wt.% WC was only 1/4 of that of the hard-facing layer. Micro-cutting with surface plastic deformation was the main wear mechanism of the substrate to form narrow and deep furrows. The wear mechanism of the hard-facing layer was mainly plastic deformation with a wide groove, and the surface cracks promoted the removal of the material. The removal of the binder phase caused by micro-cutting was the main wear mechanism of the laser cladding Ni60-WC coatings. However, the hard phase of WC hinders micro-cutting and plastic deformation, which improves the wear resistance of the coating.

Effect of Silica Size on the Relative Wear of Microstructures Containing Solidification Carbides and Tempered Martensite Using a Dry Sand Rubber Wheel Test

The objective of this study was to examine the impact of the size of silica sand particles on the wear resistance of two microstructures containing solidification M7C3 carbides in tempered martensite matrix (namely, AISI D2 steel and high-chromium white cast iron). Wear tests were conducted using abrasive silica sand particles of three different sizes (0.20, 0.50, and 1.0 mm) in a dry sand rubber wheel tribometer (DSRW) following the ASTM G65 standard. Subsequently, these samples were analyzed using microscopy and three-dimensional optical profilometry. The results showed that the wear loss increased with increased abrasive particle size, particularly when the abrasive size increased from 0.5 to 1.0 mm. The microscopic observation revealed silica sand incrustation and plastic deformation of the tempered martensite matrix, cracking of the solidification M7C3 carbides, and detachment of the carbides and matrix. Furthermore, the largest abrasive particle size triggered a more damaging wear mechanism, leading to severe fracture damage of the solidification carbides.

Experimental investigation of the effect of insert spacing on abrasion wear resistance of a composite

Reducing abrasive wear is crucial to minimising economic losses in bulk solids handling, particularly in the mining industry. The present study investigates the wear behaviour of macro-scale composites, consisting of hard inserts equi-spaced in a soft matrix, with a length-scale comparable to the size of abrasive particles. The experiments explored the effect of insert spacing on the formation of protective particle layers to reduce wear. Hardened tool steel inserts were embedded in a soft aluminium matrix. The spacing between inserts decreased with increasing volume fraction of inserts (8, 23 and 40 vol%). An instrumented dry sand rubber wheel test was used to conduct accelerated wear tests, and to measure the thickness of the protective abrasive particle layer formed during the tests. The soft aluminium matrix wore preferentially, leaving the tool steel inserts standing proud. The exposure height of the inserts reached a steady state for extended wear stages. Interestingly, the composites with 23 and 40 vol% of inserts showed significantly less wear than predicted by the rule of mixture. When the insert spacing was equal to the abrasive particle size, the thickness of the abrasive particle layer was larger than for specimens without inserts. This study reveals that the spacing between the inserts, with respect to the abrasive particle size, is an important design parameter for the development of enhanced wear resistant composites.

Influence of the wire diameter and particle fraction of Fe-Al2O3/ZrO2 flux-cored wires processed by wire arc spraying on the abrasive wear properties of the coating

The embedding of ceramic particles of a certain size and concentration in a ductile matrix is a strategy for producing wear-resistant coatings. In wire arc spraying, flux-cored wires with a metallic sheath and particle-filled core can be used for this purpose. The influence on wear properties of wire diameter and particle fraction has hardly been investigated so far. Due to the high kinetics of arc and gas flow, there are considerable challenges with regard to reproducibility, homogeneity and material efficiency. As a basis for a significantly improved understanding of the process, the relationships between the wire diameter, the particle fraction used and the wear resistance of the produced coatings have been investigated. The objects of investigation were flux-cored wires with an iron sheath and a particle filling of Al2O3/ZrO2. By using the ball-on-disc test and rubber wheel test, the wear resistance of the respective coatings was investigated.

Sensitivity analysis of the influence of particle dynamic friction, rolling resistance and volume/shear work ratio on wear loss and friction force using DEM model of dry sand rubber wheel test

The discrete element method (DEM) can improve wear model owing to its complexity. In this study, the laboratory results of the dry sand rubber wheel test (DSRWT) wear loss and friction force results at various loads (17, 35, 57, 78 and 100 N) were compared with those modelled by the DEM. The sensitivity of particle parameters (dynamic friction of rubber-sand, dynamic friction of sand-steel, and rolling resistance of the particle) was evaluated by variance, regression, and Pareto statistical analyses. The wheel and sample contact stress analyses confirmed that employing the progressive volume/shear work ratio parameter is required during the simulation; this parameter increases/decreases the wear intensity of the tested material during the simulation.

Understanding the Influence of High Velocity Thermal Spray Techniques on the Properties of Different Anti-Wear WC-Based Coatings

This work analyzes the differences found in hard metal coatings produced by two high velocity thermal spray techniques, namely high velocity oxy-fuel (HVOF) and high velocity air-fuel (HVAF). Additionally, the effect of the metallic matrix and ceramic composition and the original carbide grain size on coating properties is compared to the most studied standard reference material sprayed by HVOF, WC-Co. For this evaluation, the physical properties of the coatings, including feedstock characteristics, porosity, thickness, roughness, hardness, and phase composition were investigated. Several characterization methods were used for this purpose: optical microscopy (OM), scanning electronic microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDS), and X-ray Diffraction (XRD), among others. The final performance (abrasive wear and corrosion resistance) shown by the coatings obtained by these two methodologies was also analyzed. Thus, the abrasive wear resistance was analyzed by the rubber-wheel test, while the corrosion resistance was characterized with electrochemical methods. The characterization results obtained clearly showed that the coatings exhibit different microstructures according to feedstock powder characteristics (carbide grain size and/or composition) and the thermal spray process used for its deposition. Thus, the incorporation of WB to the cermet composition led to a high hardness coating, and the complementary hardness and toughness of the WC-Co coatings justify its better abrasion resistance. The presence of Ni on the metal matrix increases the free corrosion potential of the coating to more noble region. However, the WC-Co coatings show a lower corrosion rate and hence a higher protective performance than the rest of the coatings.

HVOF Sprayed Fe-Based Wear-Resistant Coatings with Carbide Reinforcement, Synthesized In Situ and by Mechanically Activated Synthesis

The aims of this study were: (1) to produce composite coatings by high velocity oxy fuel (HVOF) spraying with steel matrix reinforced by cermets (a) Cr3C2–20%Ni and (b) TiC–20%NiMo, manufactured by mechanically activated synthesis (MAS); (2) to synthesize in situ a carbide reinforcement for iron matrix from a mixture of titanium and carbon during HVOF reactive thermal spraying (RTS); (3) to compare the wear resistance of produced coatings. As a reference, HVOF sprayed coatings from commercial Cr3C2–25%NiCr (Amperit 588.074) and AISI 316L were utilized. Study of microstructure revealed the inhomogeneity of the Cr-based MAS coating; the Ti-based MAS coating had typical carbide granular structure, and the Ti-based RTS coating possessed elongated structures of TiC. The X-ray diffraction revealed two main phases in the Cr-based MAS coating: Cr3C2 and austenite, and two phases in the Ti-based coatings: TiC and austenite. Among the studied coatings, the Cr-based MAS coating demonstrated the highest low-force hardness (490 HV0.3). During the abrasive rubber wheel test (ASTM G65), the Ti-based MAS coating showed the best wear resistance, followed by Cr3C2–25%NiCr and Ti-based RTS coating. In the abrasive–erosive test (GOST 23.201-78), the Ti-based MAS coating was 44% better than Cr3C2–25%NiCr coating. The Ti-based RTS coating was 11% more wear resistant than the reference Cr3C2–25%NiCr coating.

Tribological performance of hardfaced and heat treated EN-47 steel used for tillage applications

In the present work, two different hardfacings, namely SZ (Super-Zed alloy; C3.83Cr33.37) and ZK (Zedalloy-K; C0.65Cr4.5Mo8.18) were deposited on EN-47 ploughshare steel by manual metal arc welding process to enhance the abrasive wear resistance. In addition, the influence of heat-treatment of steel by two different methods, i.e., carburizing (C) and through-hardening (Q&T), on the abrasive wear behaviour has also been investigated. Abrasive wear studies were conducted on bare, hardfaced, and heat-treated steel in a laboratory by using a three-body dry sand rubber wheel test rig as per the ASTM G-65 standard. The bare steel suffered a high wear rate, which may be attributed to its soft ferritic-pearlitic microstructure. The abrasive wear rate of tested specimens was found to be 1.7651 × 10−3 g m−1, 0.7439 × 10−3 g m−1, 0.961 × 10−3 g m−1, 0.992 × 10−3 g m−1 and 1.21 × 10−3 g m−1 for bare, SZ, ZK, C and Q&T steel specimens respectively. The SZ hardfacing provided better abrasive wear protection than the other treatments due to high chromium and carbon concentration in the hardfacings electrodes, which presented a higher area fraction of primary M7C3 carbides in the matrix. The wear resistance indices (WRI) for SZ hardfacing, ZK hardfacing, carburized, and through-hardened steel specimens were found to be 2.37, 1.84, 1.78, and 1.46, respectively.

The corrosion-resistant Ni-based coatings and their tribological properties

Abstract Ni-based coatings can be successfully applied under abrasive and adhesive conditions as a substitute for environmentally harmful chrome coatings. The research has been carried out for thermally flame sprayed Ni-based coatings with remelting (so-called the two-step process) with the different chemical composition of starting powders. The structure of coatings was evaluated by optical and scanning electron microscopy. Both the three-body abrasive wear test, according to ASTM G65-4 (Dry-Sand Rubber Wheel Test) and dry sliding wear test by the Falex tester, were performed. The results show the influence of the effective chemical composition of the metal powders on improving the properties of the coating. The higher hardness of the coatings leads to a lower tendency for the creation of adhesive bonds, and as a result, leads to a lower tendency to scuffing. A similar trend shows the influence of higher coating hardness on the increasing of abrasive wear resistance.

Two-body abrasion resistance of high carbon steel treated by quenching-partitioning-tempering process

The two-body abrasion behavior of a high carbon steel was investigated by applying quenching-partitioning-tempering process (Q&PT). Increasing the partitioning temperature from 250 to 400 °C, much carbon was consumed to precipitate the cementite carbides and thus less carbon was left to participate in the partitioning process, resulting in the decrease of the retained austenite volume fraction and refinement of blocky austenite. Compared with quenching-tempering treatment, both impact toughness and wear resistance of the steel were improved by applying a series of Q&PT treatments, which was associated with the formation of film-like and blocky austenite during partitioning stage. The abrasion behavior of the specimens was evaluated by both the reciprocating sliding test and rubber wheel test to increase the comparability and validness of the results. It is found that the initial hardness appeared to play a greater role in the wear resistance in reciprocating sliding wear, while the amount of retained austenite transformed during abrasion showed proportional relationship with the wear resistance in the rubber wheel test. A significant difference in groove characteristics was found in the rubber wheel wear test, revealing the narrow and deep grooves with plastic deformation and stretch-out ridges for Q&PT specimens and wide and shallow grooves with delamination at the edges for QT specimen.

Effect of TiC particles on three-body abrasive wear behaviour of low alloy abrasion-resistant steel

Low alloy abrasion resistant steel is an indispensable material used in the machinery manufacturing industry. In order to further improve its wear performance without increasing its hardness, a series of low alloy wear resistant steel reinforced with TiC particles was developed. The microstructures were characterized by SEM and TEM. The three-body abrasive wear behaviour of experimental steels has been studied using dry sand rubber wheel testing machine under different applied loads, abrasive particles, and rubber wheel rotation speeds. The results showed that the microstructure of the TiC-reinforced low alloy abrasion-resistant steel consisted of a martensite matrix and nano- and micro-sized TiC particles. Although the TiC particles consumed the C element in the matrix, thus reducing the hardness and strength of the experimental steels, the wear resistance did not decrease. The wear resistance of TiC-particle-reinforced steels was proportional to the density of the TiC particles. Furthermore, the worn surface morphology indicated that the abrasive wear mechanism of TiC-reinforced experimental steels was mainly plastic deformation, fracture, and fatigue, which is different from the micro-cutting observed in traditional low alloy abrasion-resistant steel. The different wear mechanism will aid in improving the wear performance of the steels.

Wear behavior of sansevieria cylindrica and E-glass reinforced polyester composites

Abstract The present work deals with the three body abrasive wear behavior of sansevieria cylindrica fiber (SCF) and E-glass fiber (EGF) reinforced polyester resin (PR) composites. A dry sand rubber wheel (DSRW) test set up was used to test the three-body abrasive wear behavior of composites. Composites fabrication and testing were performed as per ASTM G65-04 standards. The composites were fabricated by varying the weight percentage (wt.-%) of SCF and EGF. The DSRW test was conducted by varying the sliding distance, 1000 m and 2000 m, and the applied load, 24 N and 36 N, at a constant speed of 200 rpm. The worn out surfaces of the composites were examined using a scanning electron microscope (SEM) and the mass loss, volume loss and the specific wear rate of the composites were determined. The wt.-% 30 SCF, wt.-% 20 EGF, wt.-% 50 PR composites revealed a better wear resistance as compared with all other combinations.

The influence of process parameters on structure and abrasive wear resistance of laser clad WC-NiCrBSi coatings

In laser cladding, the final structure of coatings and thus their functional properties are dependent on process parameters used and the initial powder composition. This study focuses on laser cladding of WC-NiCrBSi coatings. As the powder used is a blend of 60% tungsten carbide spherical particles and 40% NiCrBSi matrix, the carbides’ morphology and distribution in the final coating would be dependent on laser cladding parameters. Coatings were cladded using a solid state laser and by varying key process parameters: process speed, powder feed rate and laser power. Cladded coatings are evaluated in terms of their microstructure, hardness and abrasive wear resistance tested by dry sand rubber wheel test ASTM G-65. It was found that the amount of dissolved WC carbides increases with increasing heat input and both Fe dilution and carbide dissolution affect the coatings´ properties. This shows that the selection of process parameters is crucial, as they significantly affect the final coatings´ wear resistance. In the overlay regions, the non-homogeneity of the coating’s microstructure was responsible for significant selective abrasive wear behavior.

Effect of Tungsten Carbides on Abrasive Wear of Hardfacing Coatings

The aim of this study is to investigate the abrasive wear loss as well as the wear mechanisms of hardfacing layers with and without tungsten carbides (WC) included in the matrix in different friction wheel test (FWT) configurations. The FWT setup is varied in regard to the materials of the rotating wheels, whereat steel and rubber materials are utilized to achieve varying wear mechanisms as representative conditions for stone milling as well as low density wood cutting processes. Coatings including fine particles of WC highlight the highest resistance against abrasive wear in rubber wheel testing condition, at which microcutting acts as the dominant effect. In comparison to the hardfacings without WC, the mean material loss majorly decreases by about 75%. On the contrary, the mean material loss of fine WC reinforced coatings increases up to 93% compared to the condition without WC if a steel wheel is utilized as rotating counterpart. Thereby, the coatings with comparably coarse WC reveal the minimum material loss with a decrease over 70% compared to the condition without WC. In conclusion, the inclusion of WC in hardfacing coatings significantly increases the wear resistance. The experimental wear test results highlight the fact that in order to achieve the optimal wear resistance the material characteristics of the hardfacings need to be properly defined considering the predominant wear mechanisms under in-service conditions.

Plasma Electrolytic Oxidation of High-Strength Aluminium Alloys—Substrate Effect on Wear and Corrosion Performance

With the progress in materials science and production technology and the establishment of light-weight design in many fields of the industry, the application of light metals no longer requires only mechanical strength, but also a significant protection of the material against wear and corrosion. Hard and wear-resistant oxide coatings on aluminium are produced by plasma electrolytic oxidation (PEO). During PEO, a conversion of the aluminium substrate to a ceramic oxide takes place. While the role of strength-giving alloying elements like Cu, Mg/Si, Zn, and Zn/Cu on the PEO process has selectively been subject of investigation in the past, the significance of the alloy composition for the service properties of the coatings is still unknown. Therefore, the performance of PEO coatings produced on the widely used commercial high-strength alloys AlCu4Mg1 (EN AW-2024), AlMgSi1 (EN AW-6082), and AlZn5.5MgCu (EN AW-7075) is examined with regard to their behaviour in the rubber-wheel test according to ASTM G65 and the current density-potential behaviour of the substrates with undamaged and worn coatings in dilute NaCl solution. To give a reference to the unalloyed material the testings were carried out also on Al 99.5 (EN AW-1050) which was treated in an adjusted PEO process. Although differences in the conversion of intermetallic phases during PEO and the phase composition of the coatings on the various substrates are determined, the service properties are hardly depending on the alloying elements of the investigated aluminium materials. The wear rates in the rubber-wheel test are low for all the alloyed samples. The current density-potential curves show a decrease of the corrosion current density by approximately one order of magnitude compared to the bare substrate. Eventually, previous wear of the coatings does not deteriorate the corrosion behaviour. PEO layers on technically pure aluminum can resist the testing regimes if they are prepared in an electrolyte with an elevated silicate content and without additional hydroxide ions, during a longer process time.

Three-body abrasive wear of carbide-free bainite, martensite and bainite-martensite structure of similar hardness

The three-body abrasive wear behavior of three ferrous alloys with different microstructures but similar hardness has been investigated using a standard dry-sand rubber wheel test (ASTM G65-16). Although the hardness of the alloys was similar, the abrasion rates are radically different owing to differences in abrasion mechanisms in their microstructures. A carbide-free bainitic steel having fine bainitic laths exhibited better abrasion resistance owing to the strain- induced transformation of austenite into martensite. Nano-scaled martensitic laths that formed on the surface resisted plastic deformation during abrasion and thereby increased the abrasion resistance. The microstructure containing bainitic ferrite undergoes extensive plastic deformation associated with a large quantity of dislocations, which in turn accommodates the strain of abrasion. The steel with a blocky-martensitic microstructure had the least wear resistance. In that case, fragmentation and chipping comprised the prominent abrasion mechanism. The degeneration of a martensitic structure and its subsequent tempering radically reduces the hardness at the surface and makes it more susceptible to abrasion. Steel containing a mixture of bainite and martensite had intermediate abrasion resistance relative to the other two alloys.

Surface and sub-surface damage of 0.20 wt% C-martensite during three-body abrasion

Three-body abrasive wear of 0.2wt%-C martensitic steel was conducted in a dry-sand rubber wheel test apparatus following non-standard G65-16 test procedure. The specific wear rate (SWR) of the experimental alloy was compared against other microstructures of equivalent hardness. It was observed that the SWR of the experimental alloy follows the Type-1 category, in which hardness plays a major role in controlling wear. The wear mechanism was found to be predominantly micro-cutting followed by furrow and pitting. The deformation of microstructure along the depth from the wear surface was studied by Focused Ion Beam(FIB) milling-Transmission Electron Microscopy(TEM) and X-ray diffraction (XRD), following conventional and modified Williamson-Hall and Warren-Averbach analysis. The crystallographic study reveals limited plastic deformation of martensite (α′) within a shallow depth from the worn surface, as indicated by marginal change in the character and density of dislocation, which results in higher SWR owing to the inablility of the α′-phase to accommodate the strain energy of abrasion.

Strain Hardening: Can it Affect Abrasion Resistance?

It has been largely reported in the literature that previous strain hardening has none or negligible effect on abrasive wear resistance. Those results are mainly obtained using sand rubber wheel tests and pin-on-disk tests, and have been attributed to the large strain hardening promoted by the abrasion phenomena themselves. The stresses involved in those tests are very high and the stress distributions spread toward subsurface regions at large depths. This work investigates the effects of strain hardening on low-severity (low stress at low depth) abrasive wear resistance. Microabrasion tests, normally regarded as lower stress tests, were used in order to impose low severity. Two types of stainless steels were tested: an austenitic AISI 304 steel and a ferritic AISI 430 steel. Strain hardening was obtained via thickness reduction (20%) of stainless steel sheets in a laboratory cold rolling mill. The microabrasion wear tests were carried out in a fixed-ball microabrasion tester with a three-axis load cell to continuously and simultaneously monitor the forces involved in the tests. Contrary to many findings so far in the literature, previous strain hardening increased abrasion wear resistance (55 and 63%, respectively) for both materials. Hertz calculations, simulations using Finite Element Program with explicit solution, conventional mechanical tests, microhardness profiles, microstructural analysis, and X-ray diffraction analysis were used to explain this paradigm shift for the case of microabrasion tests.

Investigation on the Tribological Behavior of Arc-Sprayed and Hammer-Peened Coatings Using Tungsten Carbide Cored Wires

Due to their outstanding properties, WC-W2C iron-based cermet coatings are widely used in the field of wear protection. Regarding commonly used WC-W2C reinforced coating systems, it has been reported that their tribological behavior is mainly determined by the carbide grain size fraction. Although the manufacturing route for arc-sprayed WC-W2C cermet coatings is in an advanced state, there is still a lack of knowledge concerning the performance of cored wires with tungsten carbides as filling material and their related coating properties when post-treatment processes are used such as machine hammer peening (MHP). A major objective was to characterize WC-W2C FeCMnSi coatings, deposited with different carbide grain size fractions as a filling using cored wires, with respect to their tribological behavior. Moreover, deposits derived from cored wires with a different amount of hard phases are investigated. According to this, polished MHP surfaces are compared to as-sprayed and polished samples by means of metallographic investigations. With the use of ball-on-disk and dry rubber wheel tests, dry sliding and rolling wear effects on a microscopic level are scrutinized. It has been shown that the MHP process leads to a densification of the microstructure formation. For dry sliding experiments, the MHP coatings obtain lower wear resistances, but lower coefficients of friction than the conventional coatings. In view of abrasion tests, the MHP coatings possess an improved wear resistance. Strain hardening effects at the subsurface area were revealed by the mechanical response using nanoindentation. However, the MHP process has caused a cracking of embedded carbides, which favor breakouts, leading to advanced third-body wear.