scholarly journals A DISCRETE ELEMENT FORMALISM FOR MODELLING WEAR PARTICLE FORMATION IN CONTACT BETWEEN SLIDING METALS

2021 ◽  
Vol 19 (1) ◽  
pp. 007
Author(s):  
Evgeny V. Shilko ◽  
Aleksandr S. Grigoriev ◽  
Alexey Yu. Smolin
Keyword(s):  
Qualitative Difference ◽  
Wear Particle ◽  
Discrete Element ◽  
Wear Particles ◽  
Surface Adhesion ◽  
Ductile Materials ◽  
Preliminary Study ◽  
Work Of Deformation ◽  
Friction Dynamics ◽  
Contact Spots

The paper describes an advanced discrete-element based mechanical model, which allows modelling contact interaction of ductile materials with taking into account fracture and surface adhesion by the cold welding mechanism. The model describes these competitive processes from a unified standpoint and uses plastic work of deformation as a criterion of both local fracture and chemical bonding of surfaces in contact spots. Using this model, we carried out a preliminary study of the formation of wear particles and wedges during the friction of rough metal surfaces and the influence of the type of forming third body (interfacial) elements on the dynamics of the friction coefficient. The qualitative difference of friction dynamics in the areas of the contact zone characterized by different degrees of mechanical confinement is shown.

Brake Wear Particle Size and Shape Analysis of Non-Asbestos Organic (NAO) and Semi Metallic Brake Pad

2014 ◽  
Vol 71 (2) ◽  
Author(s):  
Hussain, S. ◽  
M.K Abdul Hamid ◽  
A.R Mat Lazim ◽  
A.R. Abu Bakar
Keyword(s):  
Particle Size ◽  
Wear Particle ◽  
Brake Disc ◽  
Wear Particles ◽  
Brake Pad ◽  
Brake Pads ◽  
Size And Shape ◽  
Brake Wear Particles ◽  
Brake Wear ◽  
Particle Size And Shape

Brake wear particles resulting from friction between the brake pad and disc are common in brake system. In this work brake wear particles were analyzed based on the size and shape to investigate the effects of speed and load applied to the generation of brake wear particles. Scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX) was used to identify the size, shape and element compositions of these particles. Two types of brake pads were studied which are non-asbestos organic and semi metallic brake pads. Results showed that the size and shape of the particles generatedvary significantly depending on the applied brake load, and less significantly on brake disc speed. The wear particle becomes bigger with increasing applied brake pressure. The wear particle size varies from 300 nm to 600 µm, and contained elements such as carbon, oxygen, magnesium, aluminum, sulfur and iron.

scholarly journals Novel biological strategies for treatment of wear particle-induced periprosthetic osteolysis of orthopaedic implants for joint replacement

2014 ◽  
Vol 11 (93) ◽  
pp. 20130962 ◽  
Author(s):  
S. B. Goodman ◽  
E. Gibon ◽  
J. Pajarinen ◽  
T.-H. Lin ◽  
M. Keeney ◽  
...  
Keyword(s):  
Pathologic Fracture ◽  
Wear Particle ◽  
Wear Particles ◽  
Implant Loosening ◽  
Orthopaedic Implants ◽  
Periprosthetic Osteolysis ◽  
Joint Replacements ◽  
Local Inhibition ◽  
Tissue Healing ◽  
Chronic Inflammatory Reaction

Wear particles and by-products from joint replacements and other orthopaedic implants may result in a local chronic inflammatory and foreign body reaction. This may lead to persistent synovitis resulting in joint pain and swelling, periprosthetic osteolysis, implant loosening and pathologic fracture. Strategies to modulate the adverse effects of wear debris may improve the function and longevity of joint replacements and other orthopaedic implants, potentially delaying or avoiding complex revision surgical procedures. Three novel biological strategies to mitigate the chronic inflammatory reaction to orthopaedic wear particles are reported. These include (i) interference with systemic macrophage trafficking to the local implant site, (ii) modulation of macrophages from an M1 (pro-inflammatory) to an M2 (anti-inflammatory, pro-tissue healing) phenotype in the periprosthetic tissues, and (iii) local inhibition of the transcription factor nuclear factor kappa B (NF-κB) by delivery of an NF-κB decoy oligodeoxynucleotide, thereby interfering with the production of pro-inflammatory mediators. These three approaches have been shown to be viable strategies for mitigating the undesirable effects of wear particles in preclinical studies. Targeted local delivery of specific biologics may potentially extend the lifetime of orthopaedic implants.

scholarly journals A simple method of suspending implant wear particles for more physiological modelling of cell-particle interactions in vitro

2021 ◽  
Author(s):  
Christine Poon
Keyword(s):  
Wear Debris ◽  
Culture Media ◽  
Polymeric Materials ◽  
Wear Particle ◽  
Physicochemical Characteristics ◽  
Wear Particles ◽  
Simple Method ◽  
Implant Wear

AbstractArthroplasty implants e.g. hip, knee, spinal disc sustain relatively high compressive loading and friction wear, which lead to the formation of wear particles or debris between articulating surfaces. Despite advances in orthopaedic materials and surface treatments, the production of wear debris from any part of a joint arthroplasty implant is currently unavoidable. Implant wear debris induces host immune responses and inflammation, which causes patient pain and ultimately implant failure through progressive inflammation-mediated osteolysis and implant loosening, where the severity and rate of periprosthetic osteolysis depends on the material and physicochemical characteristics of the wear particles. Evaluating the cytotoxicity of implant wear particles is important for regulatory approved clinical application of arthroplasty implants, as is the study of cell-particle response pathways. However, the wear particles of polymeric materials commonly used for arthroplasty implants tend to float when placed in culture media, which limits their contact with cell cultures. This study reports a simple means of suspending wear particles in liquid medium using sodium carboxymethyl cellulose (NaCMC) to provide a more realistic proxy of the interaction between cells and tissues to wear particles in vivo, which are free-floating in synovial fluid within the joint cavity. Low concentrations of NaCMC dissolved in culture medium were found to be effective for suspending polymeric wear particles. Such suspensions may be used as more physiologically-relevant means for testing cellular responses to implant wear debris, as well as studying the combinative effects of shear and wear particle abrasion on cells in a dynamic culture environments such as perfused tissue-on-chip devices.

scholarly journals Magnetic Properties of Ferromagnetic Particles under Alternating Magnetic Fields: Focus on Particle Detection Sensor Applications

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4144 ◽  
Author(s):  
Ran Jia ◽  
Biao Ma ◽  
Changsong Zheng ◽  
Liyong Wang ◽  
Xin Ba ◽  
...  
Keyword(s):  
Magnetic Energy ◽  
Coupling Effect ◽  
Interparticle Distance ◽  
Magnetic Coupling ◽  
Wear Particle ◽  
Effective Field ◽  
Wear Particles ◽  
Force Output ◽  
Field Frequency ◽  
Sensor Applications

The electromagnetic wear particles detection sensor has been widely studied due to its ability to monitor the wear status of equipment in real time. To precisely estimate the change of the magnetic energy of the sensor coil caused by the wear particles, the magnetic property models of wear particles under the alternating magnetic field was established. The models consider the hysteresis effect and the eddy current effect of the wear particles. The analysis and experimental results show that with the increase of the effective field frequency, the change of the magnetic energy caused by the wear particles gradually decrease, which makes the induced electromotive force output by the sensor reduce with the decrease of the particle speed, so a signal compensation method is presented to obtain a unified signal when the same wear particle passing through the sensor in different speeds. The magnetic coupling effect between the two adjacent wear particles is analyzed. The result illustrates that the change of the magnetic energy caused by the dual wear particles system is larger than the sum of the energy variation caused by two independent wear particles, and with the increase of the interparticle distance, the magnetic coupling effect gradually weakens and disappears.

Classification of Wear Debris Using Weighted Fuzzy Cluster Method

2010 ◽  
Vol 33 ◽  
pp. 70-73
Author(s):  
Dai Qiang Peng ◽  
Feng Xu
Keyword(s):  
Wear Debris ◽  
Wear Particle ◽  
Fuzzy Cluster ◽  
Cluster Method ◽  
Wear Particles ◽  
Machine Condition ◽  
Machine Condition Monitoring ◽  
Fuzzy Cluster Method ◽  
The Membership Function

The analysis and identification of wear particles for machine condition monitoring is usually very time-consuming by experienced inspectors. In order to remedy the limitation, automation of the analysis procedure appears to be necessary. A novel weighted fuzzy c-means algorithm for wear particle classification is proposed in this paper. The algorithm uses the variation of the pixel intensities of a region to choose strong resembling area. Then, the spatial relationships of the membership function are constructed to regulate the pixel membership obtained from the FCM object function. Finally, wear debris are classified based on the fuzzy membership. The example shows that the method is briefly and effectively.

scholarly journals The USP14–NLRC5 pathway inhibits titanium particle–induced osteolysis in mice by suppressing NF-κB and PI3K/AKT activities

2020 ◽  
Vol 295 (20) ◽  
pp. 7018-7032 ◽  
Author(s):  
Guibin Fang ◽  
Yuan Fu ◽  
Shixun Li ◽  
Junxiong Qiu ◽  
Manyuan Kuang ◽  
...  
Keyword(s):  
Macrophage Polarization ◽  
Wear Particle ◽  
Wear Particles ◽  
Titanium Particle ◽  
Pathway Activation ◽  
M1 Macrophage ◽  
Phosphoinositide 3 Kinase ◽  
Factor Α

Total hip arthroplasty (THA) is a widely-used surgical intervention for treating patients with end-stage degenerative and inflammatory osteoarthropathy. However, wear particles from the artificial titanium joint can induce osteolysis, limiting the long-term survivorship of THA. Monocyte/macrophage lineage cells are the key players in the response to wear particles, and the proinflammatory NF-κB and phosphoinositide 3-kinase (PI3K)–AKT Ser/Thr kinase (AKT)-signaling pathways have been shown to be the most important contributors to wear particle–induced osteolysis. In contrast, ubiquitin-specific protease 14 (USP14) specifically removes the polyubiquitin chains from the nucleotide-binding and oligomerization domain (NOD)-like receptor family Caspase recruitment domain (CARD)–containing 5 (NLRC5) and thereby enhances the NLRC5-mediated inhibition of NF-κB signaling. In this study, we aimed to clarify the role of the USP14–NLRC5 pathway in wear particle–induced osteolysis in vitro and in vivo. We found that NLRC5 or USP14 overexpression inhibits titanium particle–induced proinflammatory tumor necrosis factor α (TNFα) production and NF-κB pathway activation, and it also decreases M1 macrophage polarization and PI3K/AKT pathway activation. Of note, NLRC5 and USP14 overexpression attenuated titanium particle–induced cranial osteolysis in mice. In conclusion, the findings of our study indicate that the USP14–NLRC5 pathway inhibits titanium particle–induced osteolysis by suppressing the NF-κB and PI3K/AKT pathways both in vitro and in vivo.

scholarly journals The Recombinant Protein EphB4-Fc Changes the Ti Particle-Mediated Imbalance of OPG/RANKL via EphrinB2/EphB4 Signaling Pathway and Inhibits the Release of Proinflammatory Factors In Vivo

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Yu-Wei Ge ◽  
Kai Feng ◽  
Xiao-Liang Liu ◽  
Hong-Fang Chen ◽  
Zhen-Yu Sun ◽  
...  
Keyword(s):  
Recombinant Protein ◽  
Inflammatory Response ◽  
Signaling Pathway ◽  
Osteoclast Differentiation ◽  
Wear Particle ◽  
Enzyme Linked Immunosorbent Assay ◽  
Tartrate Resistant Acid Phosphatase ◽  
Wear Particles ◽  
Proinflammatory Factors

Aseptic loosening caused by wear particles is one of the common complications after total hip arthroplasty. We investigated the effect of the recombinant protein ephB4-Fc (erythropoietin-producing human hepatocellular receptor 4) on wear particle-mediated inflammatory response. In vitro, ephrinB2 expression was analyzed using siRNA-NFATc1 (nuclear factor of activated T-cells 1) and siRNA-c-Fos. Additionally, we used Tartrate-resistant acid phosphatase (TRAP) staining, bone pit resorption, Enzyme-linked immunosorbent assay (ELISA), as well as ephrinB2 overexpression and knockdown experiments to verify the effect of ephB4-Fc on osteoclast differentiation and function. In vivo, a mouse skull model was constructed to test whether the ephB4-Fc inhibits osteolysis and inhibits inflammation by micro-CT, H&E staining, immunohistochemistry, and immunofluorescence. The gene expression of ephrinB2 was regulated by c-Fos/NFATc1. Titanium wear particles activated this signaling pathway to the promoted expression of the ephrinB2 gene. However, ephrinB2 protein can be activated by osteoblast membrane receptor ephB4 to inhibit osteoclast differentiation. In in vivo experiments, we found that ephB4 could regulate Ti particle-mediated imbalance of OPG/RANKL, and the most important finding was that ephB4 relieved the release of proinflammatory factors. The ephB4-Fc inhibits wear particle-mediated osteolysis and inflammatory response through the ephrinB2/EphB4 bidirectional signaling pathway, and ephrinB2 ligand is expected to become a new clinical drug therapeutic target.

Wear Particle Characterization and Severity Evaluation of Perodua Myvi 1.3L Automatic Transmission (AT) Fluid

2013 ◽  
Vol 393 ◽  
pp. 913-918
Author(s):  
Syazuan Abdul Latip ◽  
Salmiah Kasolang ◽  
Siti Khadijah Alias ◽  
Amirul Abd Rashid ◽  
Abdul Hakim Abdullah ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Automatic Transmission ◽  
Surface Characteristics ◽  
Wear Particle ◽  
Wear Behaviour ◽  
Particle Analysis ◽  
Wear Particles ◽  
Wear Particle Analysis ◽  
Roughness Analysis ◽  
Operating Distance

s. This paper investigates the characteristic and severity level of both wear and wear particles occurred in Perodua MyVi 1300cc automatic transmission (AT) mechanism via wear particle analysis approach. The analyses deployed were based on ferrographic and surface roughness analysis. The work of analysis strictly conducted on automatic transmission fluid (ATF) Perodua original equipment manufacturer (OEM) (ATF-3) series via continuous endurance dynamometer basis at the operating speed of 3000rpm. The operating mileage tested ranged from 0km up to 10,000km maximum operating distance. The wear particle generated at each operating mileage of 1,500km, 3,000km, 4,500km, 7,000km and 10,000km was accordingly analyzed morphologically and qualitatively. Ferrographic analysis is by principal has been recognized as one of the most reliable analysis incorporated with wear particle analysis (WPA) concern [1]. In concern of this study, it is applied to examine the morphology, mode and characteristic of wear particles generated. The surface roughness analysis meanwhile conducted to qualitatively evaluate and predict the wear condition of components within the AT mechanism via qualitative surface texture analysis of the wear particles. The outcome from the investigation done on the wear particles surface characteristics could interpret the wear behaviour and progress (stage/phase) as the surface characteristics of the wear particles do depict the surface characteristics of the wear components [2, 3].

Modelling of wear debris in planetary gear drive

2019 ◽  
Vol 71 (2) ◽  
pp. 199-204
Author(s):  
Rakesh Ranjan ◽  
Subrata Kumar Ghosh ◽  
Manoj Kumar
Keyword(s):  
Probability Distribution ◽  
Aspect Ratio ◽  
Wear Debris ◽  
Planetary Gear ◽  
Wear Particle ◽  
Distribution Model ◽  
Wear Particles ◽  
Slab Caster ◽  
Content Type ◽  
Exponential Probability

Purpose The probability distribution of major length and aspect ratio (major length/minor length) of wear debris collected from gear oil used in planetary gear drive were analysed and modelled. The paper aims to find an appropriate probability distribution model to forecast the kind of wear particles at different running hour of the machine. Design/methodology/approach Used gear oil of the planetary gear box of a slab caster was drained out and charged with a fresh oil of grade (EP-460). Six chronological oil samples were collected at different time interval between 480 and 1,992 h of machine running. The oil samples were filtered to separate wear particles, and microscopic study of wear debris was carried out at 100X magnification. Statistical modelling of wear debris distribution was done using Weibull and exponential probability distribution model. A comparison was studied among actual, Weibull and exponential probability distribution of major length and aspect ratio of wear particles. Findings Distribution of major length of wear particle was found to be closer to the exponential probability density function, whereas Weibull probability density function fitted better to distribution of aspect ratio of wear particle. Originality/value The potential of the developed model can be used to analyse the distribution of major length and aspect ratio of wear debris present in planetary gear box of slab caster machine.

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