Evaluation Of Wear Research Articles

Evaluation of Wear on Primary Tooth Enamel and Fracture Resistance of Esthetic Pediatric Crowns Manufactured from Different Materials

Background and Objectives: Advances in dental materials and CAD-CAM technology have expanded crown options in primary teeth due to their improved appearance and mechanical properties. Thus, this study aimed to assess the enamel wear and fracture resistance of prefabricated, milled, and 3D-printed esthetic pediatric crowns. Materials and Methods: The study involved 60 extracted maxillary second primary molars and 60 3D-printed resin dies, divided into six groups based on different crown materials (n = 10): prefabricated zirconia, prefabricated composite, milled composite, milled resin matrix ceramic, milled PEEK, and 3D-printed resin. Prefabricated crowns were selected after the preparation of the typodont mandibular second primary molar tooth, while milled and 3D-printed crowns were custom produced. The specimens underwent mechanical loading of 50 N at 1.6 Hz for 250,000 cycles with simultaneous thermal cycling. The 3D and 2D wear amounts were evaluated by scanning the specimens before and after aging. Then, the fracture resistance and failure types of the restorations were recorded. Results: The results showed that the milled PEEK group had superior fracture resistance compared to the other groups, while prefabricated zirconia crown group had the lowest value. Milled resin matrix ceramic crown group displayed the lowest 3D wear volume, while 3D-printed crown group showed the highest 2D wear. Conclusions: The restorative material type did not have a significant effect on the wear of primary tooth enamel. The fracture resistance of the tested materials differed according to the material type. Although the milled PEEK group showed the highest fracture resistance, all tested materials can withstand chewing forces in children.

An automatic workflow for the quantitative evaluation of bit wear based on computer vision

As global oil exploration ventures into deeper and more complex territories, drilling bit wear and damage have emerged as significant constraints on drilling efficiency and safety. Despite the publication of official bit wear evaluation standards by the International Association of Drill Contractors (IADC), the current lack of quantitative and scientific evaluation techniques means that bit wear assessments rely heavily on engineers' experience. Consequently, forming a standardized database of drilling bit information to underpin the mechanisms of bit wear and facilitate optimal design remains challenging. Therefore, an efficient and quantitative evaluation of bit wear is crucial for optimizing bit performance and improving penetration efficiency.This paper introduces an automatic standard workflow for the quantitative evaluation of bit wear and the design of a comprehensive bit information database. Initially, a method for acquiring images of worn bits at the drilling site was developed. Subsequently, the wear classification and grading models based on computer vision were established to determine bit status. The wear classification model focuses on the positioning and classification of bit cutters, while the wear grading model quantifies the extent of bit wear. After that, the automatic evaluation method of the bit wear is realized. Additionally, bit wear evaluation software was designed, integrating all necessary functions to assess bit wear in accordance with IADC standards. Finally, a drilling bit database was created by integrating bit wear data, logging data, mud-logging data, and basic drilling bit data.This workflow represents a novel approach to collecting and analyzing drilling bit information at drilling sites. It holds potential to facilitate the creation of a large-scale information database for the entire lifecycle of drilling bits, marking the inception of intelligent analysis, design, and manufacture of drilling bits, thereby enhancing performance in challenging drilling conditions.

Evaluation of wear and corrosion resistance in acidic and chloride solutions of Cathodic Arc PVD chromium nitride coatings on untreated and plasma nitrided AISI 4140 steel

Chromium nitride ceramic like coatings are well known for their hardness and wear resistance, especially under severe conditions. When deposited on mild steel, nitriding is required for such applications to create a gradient hardness profile and improve the coating adhesion and the system's mechanical properties. Corrosion resistance is also necessary since these chromium coatings are recommended for applications in the plastic mould and injection industry. Therefore, in this work, the combination of a nitriding without white layer pretreatment and CrN coating was studied in a chloride and an acidic electrolyte, to asses if the diffusion layer also plays an important role as a corrosion protection treatment. Coating microstructure, adhesion to both nitrided and non-nitrided steel, wear resistance, and corrosion resistance in chloride and acidic media were evaluated. For comparison, bare and nitrided steel were also examined. Results indicated an improvement in the adhesion for the duplex treatment (nitriding + CrN). The CrN coating demonstrated a considerably lower coefficient of friction and wear rate compared to both non-nitrided and nitrided steel. Regarding corrosion, the iron nitride layer provides some protection in chloride environments; however, in acidic media, only the CrN coating plays a protective role. In both media, localized attack occurred at sites where the coating had defects, such as pores or pinholes through which the electrolyte comes into contact with the substrate. The duplex treatment proved to be the most effective surface treatment for AISI 4140, achieving excellent tribological properties, good adhesion, and high corrosion resistance in both neutral chloride and acidic solutions.

Quantitative evaluation of pyramid belt wear using light-reflection characteristic of agglomerate coating and image processing

As a new generation of coated abrasive products with a unique pyramid-shaped structure, pyramid belt offers finer and more uniform grinding effects, and has been increasingly applied in precision grinding. However, belt wear occurs inevitably, challenging the control of shape accuracy and surface quality of ground components. Current research on pyramid belt wear is relatively limited, still lacking a universal, rapid method for observing and evaluating belt wear. In response, this paper proposes a quantitative evaluation method for pyramid belt wear using light-reflection characteristic of agglomerate coating and image processing. Firstly, a detailed analysis of the wear types and characteristics of pyramid belt is conducted. Then, focusing on the agglomerate flat wear, a method utilizing the light-reflection characteristic of agglomerate coating for observing belt wear morphology is proposed, enabling clear image capture of belt wear contours. Based on this, a wear coefficient based on the geometric characteristics of agglomerate is defined, and a quantitative evaluation method for belt wear using image processing is further proposed. The wear experiment of the belt is conducted on a robotic belt grinding platform, and experimental results show that the evaluation deviation of the proposed method from the evaluation results based on optical profilometer is within 5% at a 95% confidence interval, demonstrating the effectiveness of this method. Additionally, this method has advantages such as high computational efficiency, low cost, and good usability. Finally, the temporal evolution processes and spatial distribution patterns of belt wear and material removal rate are investigated and analyzed.

Evaluation and quantification of diffusion wear between cutting chip and workpiece using forging press

The state of the interface between the workpiece and the cutting tool affects the cutting temperature and pressure on the tool surface during the cutting process. In particular, while cutting difficult-to-cut materials such as Ni-based alloy 718, the workpiece exhibits a high affinity for cutting tool materials and could easily adhere to them. Adhesion can, at times, adversely affect productivity. The diffusion between the cutting tool and the workpiece is a factor considered to contribute to the adhesion phenomenon during cutting. Addressing this issue involves choosing tool materials and coated materials with high resistance to diffusion and optimizing cutting conditions, particularly the cutting speed, which significantly impacts cutting temperature. However, because cutting tool wear comprises various forms, clarifying the effect of diffusion on tool wear remains open. In this study, to reproduce the diffusion phenomenon between cutting tool and workpiece, two pairs of test specimens were prepared: (1) cemented carbide-AISI 1045 and (2) cemented carbide-Alloy718, which could be held at high temperature under vacuum conditions by a forging press. The degree of diffusion phenomena was evaluated at each tool-work material interface, and the quantification of diffusion amount was performed by diffused element in each work material. Additionally, the theoretical analysis of the diffusion phenomenon using the thermodynamic and phase diagram calculation software Thermo-Calc was also performed.

Evaluation of the tooth wear against different zirconia materials

Evaluation of the tooth wear against different zirconia materials

Reliability of the Assessment of Tooth Wear Severity on Dental Hard Tissues and Dental Restorations, Using the TWES 2.0, by Nonexperts.

Tooth wear is a multifactorial process resulting in the loss of dental hard tissues. For its assessment, the tooth wear evaluation system (TWES) 2.0 has been published. Previous studies on the TWES involved well-trained practitioners, rather than nonexperts. The first aim of this study was to investigate the reliability of the assessment of tooth wear severity on dental hard tissues, using the TWES 2.0, by nonexperts. The second aim was to investigate the reliability of assessment of wear severity on dental restorations, using a third scale. Forty-seven dental students evaluated at least 9 of 14 possible patient cases on dental casts and intraoral photographs. Cohen's kappa (agreement with sample solution) and Fleiss' kappa (Inter-rater reliability) were calculated. The agreements of the operators' ratings compared to the sample-solution resulted in Cohen's kappa between 0.02 and 0.9. The agreements were 0.34 for occlusal; 0.43 for vestibular; 0.57 for oral surfaces. Inter-rater reliability (Fleiss' kappa) was 0.35 for occlusal, 0.17 for vestibular and 0.24 for oral assessment. The inter-rater reliability of the ratings on tooth surfaces with restorations was lower with 0.21 (occlusal), 0.14 (vestibular) and 0.39 (oral). The agreement on different restorations differed tremendously. The ability to correctly assess the cases varied considerably between individual examiners. Within the limits of this study, assessment of restorations was slightly more challenging compared to natural teeth, particularly in occlusal regions or when the restorative material is gold. Subsequent studies should address whether enhanced training and improved definition of tooth wear grades result in higher reliability scores.

Microstructure and dry sliding wear evaluation of functionally graded coating deposited via atmospheric plasma spray

Surfaces are commonly enhanced with wear-resistant coatings to improve their resistance to abrasion, erosion, and other forms of wear. These coatings play a crucial role in extending the lifespan and improving the performance of materials and components exposed to challenging conditions. The objective of the current study is to deposit thermally sprayed 3-layer TiC–12Co–10ZrO2/NiCoCrAlMo functionally graded coatings on SS410 substrates using atmospheric plasma spray. The results revealed that by employing appropriate ceramic proportions, the microhardness of graded coatings increased to 990.4 HV, which is approximately 3.21 times higher than that of the substrate. Furthermore, the tribological properties of graded coating exhibited superior resistance compared to the substrate, where process settings were varied. Specifically, graded coating samples subjected to the applied load, sliding distance, and sliding velocity showed improved wear resistance of 78.51%, 68.42%, and 76.66% respectively in extreme conditions compared with uncoated samples. The characterization of the worn surface revealed a sequential occurrence of wear mechanisms: abrasive, adhesive, and delamination. The formation of TiO2 and Cr2O3 tribo-oxide film protects the surface against the wear mechanism and is applicable in extreme wear environments.

Mechanical and Microstructural Characterization of AISI 316L Stainless Steel Superficially Modified by Solid Nitriding Technique

AISI 316L austenitic stainless steel superficially modified by the solid nitriding technique was investigated at different nitriding times (2, 4, 6, 8, 12 and 24 h) and at 450 °C. The microstructural characterization was conducted using scanning electron microscopy (SEM) analysis and X-ray diffraction analyses, finding the presence of Fe2–3N, Fe4N and Cr2N, among others. The mechanical behavior of the modified surfaces was carried out by developing hardness profiles and relating it with the nitride layer thickness evaluated using scanning electron microscopy (SEM), obtaining layers up to 70 µm wide. The nitrogen diffusion produced species above and below the surface sample with a transformation from the austenitic phase to an expanded austenite (γN) phase, which is responsible for producing an increase in hardness of up to 1200 HV in the samples treated at 24 h, which is four times higher than the untreated steels. Wear evaluations of the obtained layers were performed using a pin-on-disk system under zero lubrication, indicating that the samples with 12 and 24 h of treatment present the best wear resistance promoted by an oxidative–adhesive mechanism. The obtained results are positively comparable with those of the ion nitriding technique but with a lower implementation cost.

Enhancing wear resistance, mechanical properties of composite materials through sisal and glass fiber reinforcement with epoxy resin and graphite filler

This study investigates the mechanical and wears properties of sisal and glass fiber-reinforced epoxy composites with graphite as filler material. We assessed the mechanical properties of the hand-layup-fabricated composite materials, including hardness, tensile strength, flexural strength, and impact strength, by ASTM standards. We also performed wear evaluations using a pin-on-disc apparatus. The results showed that the weight fractions of sisal fiber, glass fiber, graphite, and epoxy resin significantly affected the mechanical properties of the composites. In contrast to composites reinforced with individual fibers, hybrid composites exhibited enhanced mechanical properties. The optimized compositions showed improvements in tensile, flexural, impact, and hardness properties. The wear analysis revealed that a variety of factors, including the weight percentage of reinforcement, sliding velocity, load, and sliding distance, had an impact on the composites' wear resistance. The SEM images provided significant insights into the composite material's micro structural characteristics and failure mechanisms. In general, this research showcases the potential of graphite filler-reinforced sisal and glass fiber epoxy composites for use in applications that demand exceptional abrasion resistance and mechanical strength. Further refinement of the composition and processing methodologies could lead to the development of composites tailored to specific application demands.

Evaluation of wear and friction properties of graphite modified Lubri polylactic acid with various infill fabricated by additive manufacturing techniques

AbstractThree‐dimension (3D) printing technology, also known as additive manufacturing, is a manufacturing technology that creates three‐dimensional objects by depositing material layer by layer, as opposed to subtractive manufacturing methods. However, the newness of the technology brings with it many unknowns. In particular, the raw materials used are constantly increasing. For this reason, testing each raw material used in many aspects and to determine the optimum production conditions is important for the wide use of 3D printing technology. These optimal conditions may be the parameters used to produce a material, and sometimes they can appear as a new material. In addition, the production of new materials with varying production parameters is fundamental research topic that requires comprehensive study. For all these purposes, in this study, a new material type known as Lubri PLA (LPLA) was selected and produced in different filling types and subjected to a series of friction and wear tests. Thus, it is aimed to determine the tribological properties of the material. Additionally, samples were produced in ten different infill types (grid, lines, triangels, hexagon, cubic, octal, zigzag, diagonal, diagonal 3D and gyroid) to show the effect of filler type on friction and wear behavior. These filler types were used for both PLA and Lubri PLA materials and a total of twenty samples were produced. Thereby, it is aimed to conduct a comprehensive study showing the effect of both material difference and filling type on friction‐wear behavior. Diameter deviations, hardness deviations, friction coefficient, temperature, specific wear rates (SWr), and vibration were selected as output parameters. According to the analysis of the test results, the best result in terms of material structure was given by Lubri PLA, while the best result in terms of filling type was obtained with Diagonal 3D filling type. In addition, the lowest vibration level was obtained in the LP‐Diagonal 3D sample with 0.041 mm/s2, while the highest vibration level was obtained in the P‐Grid sample with 1.756 mm/s2.Highlights LPLA closed to nominal value in diameter and hardness deviations Addition of graphite nanoparticle increased the dimensional accuracy Diagonal 3D infill type Lubri PLA composites showed the superior performance Graphite modified Lubri PLA composites demonstrated superior performance

A Rock Breaking Force Prediction Model and Method of Wear Evaluation of Shield Disc Cutter in Hard Rock Stratum

A Rock Breaking Force Prediction Model and Method of Wear Evaluation of Shield Disc Cutter in Hard Rock Stratum

Design of an Innovative Twin-Disc Device for the Evaluation of Wheel and Rail Profile Wear

Design of an Innovative Twin-Disc Device for the Evaluation of Wheel and Rail Profile Wear

Evaluation of Hardness and Wear of Conventional and Transparent Zirconia Ceramics, Feldspathic Ceramic, Glaze, and Enamel.

The aim of the study was to compare the hardness, coefficient of friction, and wear experienced by four different ceramic samples: 3Y-TZP zirconium oxide ceramics-Zi-Ceramill Zi (Amman Girrbach), 5Y-PSZ transparent zirconium oxide ceramics-Zol-Ceramill Zolid (Amman Girrbach), Sak-feldspathic ceramics-Sakura Interaction (Elephant), and Glaze (Amman Girrbach). The Vickers hardness of the samples was measured. Friction tests ball-on-disc were performed between the discs of four ceramics and a zirconia ceramic ball, then a premolar tooth as a counter-sample. The mass loss and the friction coefficients of the ceramic samples were determined. The tooth counter-samples were 3D scanned, and enamel attrition depths and mass were measured. The following hardness values (HV1) were obtained: 1454 ± 46 HV1 for Zi, 1439 ± 62 HV1 for Zol, 491 ± 16 HV1 for Sak, 593 ± 16 HV1 for Glaze, and 372 ± 41 HV1 for enamel. The mass losses of the teeth in contact with ceramics were 0.1 mg for Zi, 0.1 mg for Zol, 5.5 mg for Sak, and 4 mg for Glaze. Conventional and transparent zirconium oxide ceramics are four times harder than enamel and three times harder than veneering ceramics. Zirconia ceramics exhibit lower wear and a more homogenous, smoother surface than the other ceramics. Tooth tissues are subject to greater attrition in contact with veneering ceramics than with polished zirconium oxide ceramics.

Evaluation of tool wear and surface roughness in high-speed dry turning of Incoloy 800

Evaluation of tool wear and surface roughness in high-speed dry turning of Incoloy 800

Evaluation of surface response of SiC and fly ash-filled Prosopis juliflora fibre-reinforced epoxy composites under dry sliding wear conditions using Taguchi method

Prosopis juliflora (PJ) fibre-reinforced polymer composites are fabricated with fly ash and SiC as fillers with different weight percentages. Jute layers are also sandwiched for added strength in the structure. The wear behaviour is found for the prepared composition of samples. Pin-on-disc wear testing apparatus is used for the wear performance along with the design of experiments approach using orthogonal arrays of Taguchi’s. The effect of the input parameters (load, sliding velocity, speed) is studied on wear resistance. The experimental design creates sliding wear evaluations based on Taguchi’s L9 orthogonal array to identify the most dominating factors influencing the wear rate. This study demonstrates that the most important component affecting the sliding wear rate of the composite materials is followed by the sliding velocity, speed, and load. The result of the wear rate decreases with an increase in filler content and also increases with sliding velocity. The samples with fly ash and SiC fillers reportedly seemed to have the best wear rates.

An evaluation of antagonist enamel wear opposing full-coverage zirconia crowns versus other ceramics full-coverage crowns and natural enamel - An umbrella review.

The aim of this umbrella review was to systematically review the systematic reviews on antagonist enamel wear opposing zirconia crowns compared to other ceramics and natural enamel. This was an umbrella review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. An electronic search of PubMed, Cochrane Central, EBSCOhost, and Google Scholar search engines for articles published from January 1, 2013, to January 1, 2023, was conducted using keywords "enamel wear," "zirconia," "feldspathic," "dental ceramics," and "Y-TZP" to identify systematic reviews on antagonist enamel wear opposing zirconia crowns compared to other ceramics and natural enamel. Qualitative analysis. A total of 86 articles were obtained through electronic search, of which four articles were selected after abstract screening that met the inclusion criteria for evaluating antagonist enamel wear. As compared to feldspathic groups, zirconia had substantially less antagonist wear, while surface polishing exhibited less enamel wear than glazing. Because of the heterogeneity in study design, measurement methods, and outcome variables, a meta-analysis was not possible. Over time, the opposing enamel wear caused by polished monolithic zirconia will be either equal to or less than that of natural enamel wear. Polished monolithic zirconia also maintains lower values of enamel wear compared to metal ceramics, feldspathic porcelains, and lithium disilicate.

Self-Supervised Transfer Learning for Remote Wear Evaluation in Machine Tool Elements With Imaging Transmission Attenuation

Self-Supervised Transfer Learning for Remote Wear Evaluation in Machine Tool Elements With Imaging Transmission Attenuation

Evaluation of tool wear during micro-milling of ultrasonically assisted abrasive peened Ti-6Al-4V

When a cutting tool shears through a workpiece, the interaction causes wear of the tool which is based on relative hardness, surface characteristics of the tool and the workpiece, cutting environment and thermal behaviour at the work/tool interface. In this study, wear of a micro-end milling tool is investigated while milling of as-received and peened work material (in this case, Ti-6Al-4V). The peening is performed with the help of an in-house developed ultrasonic cavitation process. The process excites the abrasives suspended in the cavitating medium, which impart on the work surface and induce compressive residual stress and uniform grain refinement. As the cutting process advances, a built-up is formed more rapidly in the as-received workpiece, leading to higher cutting forces and earlier chipping of the cutting edge. Under the peened conditions, it is found that the increase in tool edge radius and flank wear width reduce by 50 % and 54 % respectively compared to the as-received one. Additionally, peening-induced grain refinement leads to a 26 % decrease in surface roughness of the machined surface and inhibits burr formation by 60 %. A tool wear chipping model is employed to predict the tool diameter, cutting edge radius and flank wear width of the worn tool. Results show that the magnitude of flank wear, edge radius of worn tool and tool diameter deviate from experiments by 15.2 %, 14 % and 13 % respectively.

Dental Erosive Wear Assessment amongst Different Age Groups Utilising Basic Erosive Wear Examination: An Epidemiological Study

Introduction: The study aims to assess the prevalence of erosive tooth wear and risk levels amongst different age groups utilising Basic Erosive Wear Examination (BEWE) amongst the population of South West Coastal India. Materials and Methods: One hundred and sixty healthy people participated in the research (n = 32 per group). Using sextants and the BEWE, index (0–18) allowed for the evaluation of erosive tooth wear. Questionnaires supplemented clinical data. Each participant was assigned to groups based on the severity of their erosive wear: high (BEWE sum ≥ 14), moderate (BEWE sum 9–13), low (3–8) and none (0–2). Results: There is no significant difference in the degree of erosive tooth wear across different age groups (χ2– 20.11, P – 0.067 [not-significant]). There is a significant difference in response to questions across different age groups (χ2 – 487.21, P – 0.01 [significant]). Conclusion: The prevalence of erosive tooth wear grows as individuals age. Older age groups, patients who are at a higher risk level require a more comprehensive form of treatment. The aetiology of dental erosion remained unknown to the patients, indicating a deficiency in their understanding of erosive tooth wear.