Surface Abrasion Research Articles

Surface Hardness and Abrasion Threshold of Chemically Strengthened Soda-Lime Silicate Glasses After Steam Processing

Chemical strengthening by diffusive ion exchange (IOX) is a common method to improve the mechanical performance of glass products. However, the process of ion-stuffing is often associated with an increase of surface hardness and a decrease of the resistance to abrasive wear during scratching, even when the thickness of the exchanged layer is low. Autoclave steam-treatment presents a way to compensate the enhanced surface brittleness accompanying IOX. It causes a notable shift in the load threshold for microabrasion to more abrasion-resistant glasses. Subject to the specific processing parameters, the softening effect is constrained to a surface layer of less than 500 nm in thickness; therefore, the overall compressive stress profile is not affected and the advantages of IOX strengthening are retained. In turn, ion-stuffing by IOX counteracts severe autoclave corrosion of soda-lime silicate glasses, making them suitable for a combination of both processes.

The Influence of Alumina Airborne-Particle Abrasion with Various Sizes of Alumina Particles on the Phase Transformation and Fracture Resistance of Zirconia-Based Dental Ceramics.

The surface of zirconia-based dental ceramic restorations require preparation prior to adhesive cementation. The purpose of this study was to assess the influence of airborne-particle abrasion with different sizes of alumina particles (50 μm, 110 μm, or 250 μm) on the mechanical strength of zirconia-based ceramics' frameworks and on the extent of phase transformations. A fracture resistance test was performed. The central surface of the frameworks was subjected to a load [N]. The identification and quantitative determination of the crystalline phase present in the zirconia specimens was assessed using X-ray diffraction. The Kruskal-Wallis one-way analysis of variance was used to establish significance (α = 0.05). The fracture resistance of zirconia-based frameworks significantly increases with an increase in the size of alumina particles used for air abrasion: 715.5 N for 250 μm alumina particles, 661.1 N for 110 μm, 608.7 N for 50 μm and the lowest for the untreated specimens (364.2 N). The X-ray diffraction analysis showed an increase in the monoclinic phase content after air abrasion: 50 μm alumina particles-26%, 110 μm-40%, 250 μm-56%, and no treatment-none. Air abrasion of the zirconia-based dental ceramics' surface with alumina particles increases the fracture resistance of zirconia copings and the monoclinic phase volume. This increase is strongly related to the alumina particle size.

Research on the wear performance of reactive plasma deposited TiB2-TiC0.3N0.7 matrix coating

Wear performance and behavior of as-sprayed TiB2-TiC0.3N0.7 matrix coating were investigated with different rotation speeds of counterpart and applied load. Analytical balance was used to weigh wear quantity. Scanning electron microscopy was used to observe surface morphology, abrasion scratch, and wear debris was researched through an energy dispersive spectrum. It is found the mass loss of matrix coating increases with the loading load increment at a low rotation speed of the counterpart. And wear loss decreases first and then increases with the increment of loading load at the high rotary speed of the counterpart. The wear mechanism of abrasive wear, adhesion wear, oxidation wear, and fatigue wear appear during the test of composite coatings at different rotation speeds of the counterpart and applied load.

Fabrication and testing of a multifunctional SiO2@ZnO core–shell nanospheres incorporated polymer coating for sustainable marine transport

We report the development of a coating system relying on the incorporation of SiO2@ZnO core–shell nanospheres in polyurethane media as a novel approach to achieve longevity and sustainability in marine transport. This polymeric coating showed significant improvement in surface abrasion resistance, the transition from a hydrophilic state to a hydrophobic state (~ 125.2° ± 2°), improved antifungal, antibacterial and antialgae effects which make the proposed coating ideal to protect steel surfaces against biofouling. To substantiate our claims, we performed X-ray diffraction, Transmission electron microscopy, Fourier transform infrared spectroscopy, scanning acoustic microscopy, Thermogravimetric analysis (TGA), contact angle measurements, antimicrobial (antialgal, antibacterial, antifungal) tests and Taber abrasion tests (ASTM D1044 and D4060) to highlight the mechanical and biological functionality as well as the bonding configuration of this coating. The wear analysis of the Taber abraded coating using SEM and optical microscopy showed significant improvement in the adhesion and shear resistance achieved by the SiO2@ZnO core–shell nanospheres incorporated PU coating which was a contrasting feature compared to using PU alone. The overall investigations we performed led us to find out that the addition of 4% (wt.) SiO2@ZnO core–shell nanoparticles to the PU media deposited on the low carbon steel surface demonstrated remarkable antimicrobial performance with almost no bacterial growth, significant reductions in growth for algae to about 90% and fungus to about 95%.

An Elucidative Review of the Nanomaterial Effect on the Durability and Calcium-Silicate-Hydrate (C-S-H) Gel Development of Concrete.

Concrete as a building material is susceptible to degradation by environmental threats such as thermal diffusion, acid and sulphate infiltration, and chloride penetration. Hence, the inclusion of nanomaterials in concrete has a positive effect in terms of promoting its mechanical strength and durability performance, as well as resulting in energy savings due to reduced cement consumption in concrete production. This review article discussed the novel advances in research regarding C-S-H gel promotion and concrete durability improvement using nanomaterials. Basically, this review deals with topics relevant to the influence of nanomaterials on concrete's resistance to heat, acid, sulphate, chlorides, and wear deterioration, as well as the impact on concrete microstructure and chemical bonding. The significance of this review is a critical discussion on the cementation mechanism of nanoparticles in enhancing durability properties owing to their nanofiller effect, pozzolanic reactivity, and nucleation effect. The utilization of nanoparticles enhanced the hydrolysis of cement, leading to a rise in the production of C-S-H gel. Consequently, this improvement in concrete microstructure led to a reduction in the number of capillary pores and pore connectivity, thereby improving the concrete's water resistance. Microstructural and chemical evidence obtained using SEM and XRD indicated that nanomaterials facilitated the formation of cement gel either by reacting pozzolanically with portlandite to generate more C-S-H gel or by functioning as nucleation sites. Due to an increased rate of C-S-H gel formation, concrete enhanced with nanoparticles exhibited greater durability against heat damage, external attack by acids and sulphates, chloride diffusion, and surface abrasion. The durability improvement following nanomaterial incorporation into concrete can be summarised as enhanced residual mechanical strength, reduced concrete mass loss, reduced diffusion coefficients for thermal and chloride, improved performance against sulphates and acid attack, and increased surface resistance to abrasion.

Biodegradation behavior of polybutylene succinate (PBS) fishing gear in marine sedimentary environments for ghost fishing prevention

This study evaluated the biodegradability of PBS fishing gear in marine sedimentary environments, which is a major cause of unintended catches caused by discarded fishing gear, known as “ghost fishing”. Based on the biodegradation analysis according to ISO 19679, the PBS fishing gear was converted into carbon dioxide by 27.3% for 180 days. After biodegradation, the remaining PBS exhibited a characteristic molecular weight decrease, indicating bulk erosion, but there was no change in crystallinity and thermal properties. Ultimately, degradation of the PBS proceeded primarily through surface abrasion with metabolic utilization of hydrolysis products by microorganisms. Biological studies showed that the Rhodococcus genus was the dominant microbe for PBS biodegradation. In an accelerated evaluation experiment using a lipase enzyme known to be produced by dominant bacteria, the PBS showed a high biodegradability of 48% in 10 days. From the perspective of biodegradation, biodegradable fishing gear can not only replace existing nondegradable fishing gear but also prevent ghost fishing through biodegradation in the marine sedimentary environment after use.

Influence of bio-inspired surface texture of additively manufactured 17-4 PH stainless steel adherends on the strength of adhesively bonded joints

The bonding potential of as-printed additively manufactured stainless steel is largely unknown, and the use of additional hierarchical bio-inspired surface texture has not yet been explored or characterized. In this study, it is demonstrated with the use of Selective Laser Melting (SLM) that a hierarchy of three surface features at different length scales can greatly improve the shear strength of metal-metal adhesive joints. The intrinsic stochastic texture of the SLM as-printed surface showed a high contact angle and a mixed failure with a dominance of adhesive failure. However, enhancing the as-printed surface with the Tree Frog (TF) and Fish Scale (FS) bio-inspired textures produced super-wetting surfaces, significantly improving the shear strength due to the synergistic effect of mechanical interlocking and physical adsorption adhesion mechanisms, resulting in mixed failure. The results indicated that the interfacial bonding performance was in line with the super-wetting behavior and was higher for the samples with a hierarchy of three surface features. The highest increase in bond strength was found for the tree frog hierarchical hexagonal texture (+70% compared to the as-printed texture). In contrast, abrasion of the as-printed surface with P1000-grit paper significantly reduced the surface roughness and increased the water contact angle, resulting in the lowest shear strength.

Repair of Worn-Out Parts of Auger Presses by Surfacing Method

In the briquetting process of various finely dispersed materials using the auger pressing method, an important issue is extending the service life and repairing worn-out elements, such as the auger, die, and lining. This study provides a literature review and industrial experience in repairing worn-out parts of industrial presses. It formulates the main approaches for restoring abrasive surfaces and presents the results of experimental studies aimed at prolonging the lifespan of augers in briquette presses using surfacing methods, including using powders obtained from solid alloy waste.

PECULIARITIES OF THE MASTICATORY APPARATUS OF GUINEA PIGS (Cavia porcellus)

Guinea pigs (Cavia porcellus) are rodents that feed on grassy plants, buds and sprouts, with cheek teeth having specialised abrasive surfaces for plant grinding. In analysing the prehension and trituration ways of guinea pigs, many differences concerning mandible conformation, the positioning of cheek teeth and the morphology of the masticatory muscles compared to other rodents were found. Masticatory muscles of guinea pigs are predominant compared to the mimetic muscles which are reduced. Compared to other rodents, in guinea pigs, inside the tendon thickness of the superficial part of the masseter muscle there are two rounded cartilaginous structures such as sesamoids. The dorsal one is larger, measuring about 3–4 mm in diameter having the role of reducing pressure on the tendon when it passes over the mandible ridge. The other is ventrally placed, about 2–3 mm in size and protects the tendon of the superficial part of the masseter muscle when it passes over the ventral tubercle of the mandible.

Abrasive Wear Behaviour of Organophosphate

Wear is very important phenomena which play a vital role while designing any component. It directly affects the life of the component. Abrasive wear phenomena are simply caused by the passage of relatively hard particles or asperities over a surface. Abrasive wear simply includes division of two surface parts by abrasion of other mating surface that is situated between the friction areas. A systematic study of abrasive wear of Silicon has been carried out using a two body pin-on-disc wear machine. The objective of this study is to evaluate the abrasive wear of organophosphate by grinding it at different load at different rpm. In this thesis a study of abrasive wear of organophosphate at different speed were given to analyze the possibility of wear. A review of abrasive wear behavior of organophosphate using different wear rate speed has been discussed in this thesis. Mainly focus on the varying wear condition during varying rpm. as we all know that wear is very important parameter which directly affects the life of a component. The goal of this study was to evaluate abrasive wear only. Key Words: Abrasive wear, Behaviour of organophosphate, Wear rate

External fibrillation of wood pulp

Pulp refining produces external fibrillation consisting of fibrils tethered to fiber surfaces, in addition to loose fibrils and fines. Both contribute to a larger bonding area that increases paper strength, but tethered fibrils have less likelihood of being washed out during papermaking. This study postulates the mechanism by which refining produces external fibrillation and the optimum conditions for doing so. The postulated mechanism is surface abrasion during sliding of fibers in refiner gaps. External fibrillation occurs when forces are great enough to partially dislodge fibrils from fiber surfaces, but not large enough to break the fibrils. The refining intensities to achieve these forces were determined by a mathematical model and experiments using a laboratory disc refiner. The optimum intensities in terms of specific edge load (SEL) for chemical pulps were about 0.1 J/m for hardwoods and 1.0 J/m for softwoods An extension of this study suggested that abrasion may also account for most of the energy consumed in the mechanical pulping process.

Grinding Path Planning of Abrasive Cloth Wheel Based on Modified Preston Equation

As for the efficient and high-precision grinding of blades, it was studied that a flexible grinding path planning method of the abrasive cloth wheel of the blades. In the paper, based on modified Preston equation, the radial material removal depth model is supplemented, which provides theoretical support for the establishment of the flexible grinding path of the abrasive cloth wheel. After obtaining the abrasive cloth wheel envelope surface by the double parameter sphere family method, the deformation amount of the abrasive cloth wheel is used as the directed distance from the point of the designed surface to the envelope. The sequential linear optimization algorithm is used to optimize the directed distance. Then, the flexible grinding path for constant material removal is obtained. The results of the simulation show that the profile error of the blade processing is improved under the requirements of surface roughness.

Effect of Cryo-Treated Cutting Tool End Milling on Custom 450 Stainless Steel.

Custom 450 stainless steel is the most desirable material across industries due to its widespread application in the aerospace, defense and marine industries. Stainless-steel materials are challenging to deal with and fall into the list of hard-to-process materials due to their low heat conduction coefficient and high mechanical properties. In this research work, end milling was carried out on Custom 450 stainless steel machined using TiAlN coated with tungsten carbide inserts that have been cryo-treated (CT) for 24 h (24 h) and 36 h (36 h), as well as untreated (UT) inserts. The inserts were evaluated in terms of feed force, feed rate and consistent depth of cut (ap) at various spindle speeds (S). Also examined were the tool morphology, chip anatomy and surface morphology of cryo-treated material compared to untreated inserts at various responses to cutting force (Fx, Fy, Fz), cutting temperature (Tc), vibration and surface abrasion. For inserts that have been cryo-treated for 36 h, the feed force (Fx) value was 44% and 5% less compared to inserts treated for 24 h and in UT inserts, respectively. Furthermore, for 24-h and 36-h CT inserts, feed force (Fx) was 12% and 20% less compared to a UT insert. Using 24-h cryo-treated inserts as opposed to UT inserts significantly reduced the surface roughness by 20%. Cutting inserts that have undergone cryogenic treatment have been observed to exhibit longer cutting tool life due to less wear and friction on the cutting edges.

Strengthening Mechanism of Nanosized Magnesium Silicate Hydroxide on the Tribological Properties of Phosphate-Bonded Solid Coatings

Natural serpentine and nanosized magnesium silicate hydroxide (MSH) were separately incorporated to improve the tribological properties of phosphate-bonded solid coatings. The differences in tribological properties between natural serpentine and MSH at different temperatures were elaborately explored. It was suggested that MSH can more apparently improve the antiwear performance of phosphate coatings than natural serpentine. The specific reasons were attributed to the big specific surface area and weak thermal stability of MSH. Under the combined effort of frictional force and friction temperature, the structural water in MSH can be easily dehydrated and can generate numerous dangling bonds on the outside surface. Simultaneously, structural distortion of MSH also inevitably occurred, which resulted in lots of oxygen functional groups of MSH being released at the frictional interface during the friction process. Besides, MSH has a strong cation replacement ability, and therefore, it can easily adsorb and undergo tribochemical reactions with the metal-based worn surface. In consequence, a composite protective tribo-film was in situ formed on the worn surface and direct abrasion on the worn surface was greatly alleviated during the friction process. The results offered an approach for designing and preparing antiwear phosphate composite solid coatings for the tribological applications of metal-based friction pairs at different friction temperatures.

Insights into the mechanism of plastics’ fragmentation under abrasive mechanical forces: An implication for agricultural soil health

AbstractThe application of agricultural plastic products such as mulch, greenhouse covers, and silage films is increasing due to their economic benefits in providing an early and better‐quality harvest. However, mechanical abrasion of these plastic materials by soil particles could result in generation of microplastic (MP) pollutants that could harm soil organisms and impact food safety. This study aims to better understand the physicochemical mechanisms resulting in the fragmentation of low‐density polyethylene (LDPE). Herein, we used pellets and films to study the impacts of abrasive wear forces on their surface morphology variations and fragmentation behavior. An innovative laboratory approach was developed to abrade the plastic surface under controlled normal loadings and abrasion durations. The investigation of the plastics’ surface morphology variations due to the abrasion process revealed microcutting as the dominant process at low normal force (4 N). However, a combination of microploughing and microcutting occurred for new LDPE films by increasing the normal force to 8 N. Despite the significant surface morphology variations of the new LDPE film due to the abrasion process; the water contact angle did not alter. Furthermore, the fragmentation behavior of photodegraded LDPE pellets and films was compared to the new plastics. The extent of MPs (3 µm < dp < 162 µm) generation due to fragmentation was studied using fluorescence microscopy imaging. The localized stress and strains at the contact sites of plastic and sand particles resulted in abrasion of the plastic surface. According to the results, the normal loadings and duration of abrasion played a significant role in the degree of fragmentation of plastics. Increasing the normal loading applied during the abrasion process from 2 to 8 N linearly increased the number of generated plastic fragments by more than five times for pellets and more than three times for film. Photodegradation significantly enhanced the extent of MPs fragmentation. Moreover, the limitations of this study and the implications for agricultural soil health were discussed.

Raman Spectroscopy and Machine Learning Enables Estimation of Articular Cartilage Structural, Compositional, and Functional Properties.

To differentiate healthy from artificially degraded articular cartilage and estimate its structural, compositional, and functional properties using Raman spectroscopy (RS). Visually normal bovine patellae (n = 12) were used in this study. Osteochondral plugs (n = 60) were prepared and artificially degraded either enzymatically (via Collagenase D or Trypsin) or mechanically (via impact loading or surface abrasion) to induce mild to severe cartilage damage; additionally, control plugs were prepared (n = 12). Raman spectra were acquired from the samples before and after artificial degradation. Afterwards, reference biomechanical properties, proteoglycan (PG) content, collagen orientation, and zonal (%) thickness of the samples were measured. Machine learning models (classifiers and regressors) were then developed to discriminate healthy from degraded cartilage based on their Raman spectra and to predict the aforementioned reference properties. The classifiers accurately categorized healthy and degraded samples (accuracy = 86%), and successfully discerned moderate from severely degraded samples (accuracy = 90%). On the other hand, the regression models estimated cartilage biomechanical properties with reasonable error (≤ 24%), with the lowest error observed in the prediction of instantaneous modulus (12%). With zonal properties, the lowest prediction errors were observed in the deep zone, i.e., PG content (14%), collagen orientation (29%), and zonal thickness (9%). RS is capable of discriminating between healthy and damaged cartilage, and can estimate tissue properties with reasonable errors. These findings demonstrate the clinical potential of RS.

Underwater surface abrasion of conventional and geopolymer concrete using the ASTM C1138 approach

This study focuses on the development of unique geopolymer-based composites made using industrial byproducts and waste materials. The first test variable was the compressive strength grade, where conventional concrete specimens with ordinary Portland cement (OPC) and GPC specimens having three target design strengths (20, 30 and 40 MPa) were prepared and tested. All specimens were tested at different ages, which is the second variable of the study, where early ages (3 and 7 days) and mature age (28 days) were adopted. It is worth mentioning that both geopolymer and concrete samples had the exact quantities of filler and binder materials. Then, the specimens were tested following the procedure of standard ASTM C1138 approach under-water abrasion tests, which were conducted at 6 intervals of 12 h each. The recorded abrasion results revealed higher abrasion losses for specimens with lower design strengths regardless of the type of concrete. Besides, the influence of the sample's age on enhancing the abrasion resistance was more apparent in conventional concrete samples than geopolymer ones since the last gained their design strength early, about three days. The GPC specimens exhibited lower abrasion losses compared to their corresponding OPC ones revealing a better abrasion resistance. The difference was the highest at the age of 3 days due to the early strength development of GPC. The abrasion resistance enhancement of GPC specimens compared to their corresponding OPC ones at 3 days was 72% for the design strength of 20 MPa and around 55% for the higher design compressive strengths.

Sliding wear characteristics of FDM-processed polylactic-acid in bovine blood serum

Fused deposition modelling (FDM) has so far been recognized for its reliability and simplicity for manufacturing of geometrically-complex polymeric materials with 3D printing technique. Recently, the studies concerning the properties of materials fabricated by using the FDM have been growing, including those related to their wear resistance which is considered of critical when a 3D-printed material must work sliding over the surface of another material during its application. Up to now, however, the influence of several FDM-printing parameters, including the raster orientations, on the wear resistance of the printed polymeric materials have not yet been fully understood. In this research, the influence of raster orientations on the wear resistance of FDM-processed polylactic-acid (PLA) materials in bovine blood serum were determined. A reciprocating pin-on-plate tribometer was used to evaluate wear resistance of a cylindrical PLA pin that slid over the surface of a commercially-pure titanium (Ti) plate. The results showed that the FDM-printed PLA pins with unidirectional raster orientations had higher wear factors (WF), i.e., ~1.5 ´ 10-4 mm N-1 m-1 than those with crossed raster orientations, i.e., ~0.8 ´ 10-4 mm N-1 m-1. Meanwhile, the WF values of Ti surface that slid against PLA pin with crossed raster orientations, i.e., ~0.09 ´ 10-4 mm N-1 m-1, were also significantly lower than those sliding with the pin having unidirectional raster orientation, i.e., 0.34 – 0.41 ´ 10-4 mm N-1 m-1. The result of analysis of the worn surface morphologies shows the indications of surface abrasion, fatigue and polymer film transfer as the possible wear mechanisms of both the FDM-processed PLA pin and its Ti countersurface material. On the basis of all the findings in this research, it can be concluded that the crossed raster orientation is preferable to be used as one of the parameters in printing of the wear resistant PLA rather than the unidirectional raster orientation.

Optimum Driving of Ultrasonic Cleaner Using Impedance and FFT Analysis with Validation of Image Processing of Perforated Foils

Over the past decade, ultrasonic cleaners have been widely used in many industries. Now, this technology is finding its way into homes for vegetable, fruit, and clothes cleaning. In widely used ultrasonic cleaners, piezoelectric transducers are externally attached to the steel tank to generate ultrasonic waves inside the tank. Based on the impedance data of the piezoelectric transducers, the driving circuit was tuned to generate the required frequencies inside the cleaning tank. This paper discusses the design, development, and validation of an 800 mL tank capacity ultrasonic cleaner driven with a piezoelectric disc actuator. To achieve an optimum cleaning action without surface abrasion, several characteristics need to be considered in this complex relationship. The placement of transducers has been investigated according to the pressure distribution inside the liquid medium. The optimized ultrasonic cleaner design, along with a class-D half-bridge circuit, was developed to drive the ultrasonic transducer in the resonance frequency range. To validate the optimal design and driving frequency, the acoustic spectrum generated inside the tank was measured using a piezoelectric sensor and FFT analysis was performed. To validate the cleaning effect, a qualitative test based on aluminuim foil perforations was performed. The perforation area in the foils was quantitatively measured using image processing based on the YOLO V5 technique. The proposed image processing technique has an accuracy of 97 % in the detection of perforation areas in the aluminuim foil test.

Mechanical properties of additively manufactured zirconia with alumina air abrasion surface treatment

This study aimed to evaluate the mechanical properties of zirconia fabricated using additive manufacturing technology and compare them to those of zirconia fabricated using subtractive manufacturing technology. Sixty disc-shaped specimens were fabricated for the additive (n = 30) and subtractive manufacturing groups (n = 30), and each group was divided into two subgroups according to their air-abrasion surface treatment: control (n = 15) and air-abrasion groups (n = 15). Mechanical properties including the flexural strength (FS), Vickers hardness, and surface roughness were determined, and the values were analyzed by one-way ANOVA and Tukey’s post hoc test (α = 0.05). X-ray diffraction and scanning electron microscopy were used for phase analysis and surface topography evaluation, respectively. The SMA group exhibited the highest FS (1144.97 ± 168.1 MPa), followed by the SMC (944.58 ± 141.38 MPa), AMA (905.02 ± 111.38 MPa), and AMC groups (763.55 ± 68.69 MPa). The Weibull distribution showed the highest scale value (1213.55 MPa) in the SMA group, with the highest shape value in the AMA group (11.69). A monoclinic peak was not detected in both the AMC and SMC groups, but after air abrasion, the monoclinic phase content ({mathrm{X}}_{mathrm{m}}) reached 9% in the AMA group, exceeding that in the SMA group (7%). The AM groups exhibited statistically lower FS values than those of the SM groups under the same surface treatment (p < 0.05). Air-abrasion surface treatment increased the monoclinic phase content and FS (p < 0.05) in both the additive and subtractive groups, while it increased the surface roughness (p < 0.05) only in the additive group and did not affect the Vickers hardness in either group. For zirconia manufactured using additive technology, the mechanical properties are comparable to those of zirconia manufactured using subtractive technology.