Wear Characteristics of Medical Hearing-Aid Components and Friction Reduction Mechanisms

The wear characteristics of a hearing-aid battery assembly, which consist of an acrylonitrile-butadiene-styren (ABS) button cell compartment and a stainless steel bracket with the locking knob, have been studied in the current work to predict its lifespan in service. The main failure mechanism is the worn-out of the cell compartment by the locking knob when changing the battery. Its wear rate is determined by the relationship between knob geometry and corresponding pressure distribution on the worn surface. Due to the third-body entrapment, the wear rate is highly influenced by the presence of the debris, and fortunately, it can be reduced by applying microsurface texture onto the knob. Experiments are conducted here to validate the wear reduction mechanism.

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Tribological Behaviour of Graphene Nanoplatelets as Additive in Pongamia Oil

Coatings ◽

10.3390/coatings11060732 ◽

2021 ◽

Vol 11 (6) ◽

pp. 732

Author(s):

Yeoh Jun Jie Jason ◽

Heoy Geok How ◽

Yew Heng Teoh ◽

Farooq Sher ◽

Hun Guan Chuah ◽

...

Keyword(s):

Friction And Wear ◽

Graphene Nanoplatelets ◽

Friction Reduction ◽

Engine Oil ◽

Protective Film ◽

Tribological Behaviour ◽

Wear Reduction ◽

Pongamia Oil ◽

Interacting Surfaces ◽

Worn Surface

This study investigated the tribological behaviour of Pongamia oil (PO) and 15W–40 mineral engine oil (MO) with and without the addition of graphene nanoplatelets (GNPs). The friction and wear characteristics were evaluated in four-ball anti-wear tests according to the ASTM D4172 standard. The morphology of worn surfaces and the lubrication mechanism of GNPs were investigated via SEM and EDS. This study also focuses on the tribological effect of GNP concentration at various concentrations. The addition of 0.05 wt % GNPs in PO and MO exhibits the lowest friction and wear with 17.5% and 12.24% friction reduction, respectively, and 11.96% and 5.14% wear reduction, respectively. Through SEM and EDS surface analysis, the surface enhancement on the worn surface by the polishing effect of GNPs was confirmed. The deposition of GNPs on the friction surface and the formation of a protective film prevent the interacting surfaces from rubbing, resulting in friction and wear reduction.

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Experimental Research of Scuffing of Friction Pair

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.697.254 ◽

2014 ◽

Vol 697 ◽

pp. 254-257

Author(s):

Jie Lin Xu ◽

Zeng Xiong Peng ◽

Nan Wang ◽

Shan Lin Xu

Keyword(s):

Friction Coefficient ◽

Wear Rate ◽

High Speed ◽

Friction And Wear ◽

Friction Pair ◽

Common Phenomenon ◽

Working Pressure ◽

Wear Characteristics ◽

Worn Surface ◽

Friction And Wear Characteristics

The scuffing of friction pair is a common phenomenon in conditions of high speed and pressure. It was researched on scuffing characteristics in this paper. By using UMT-3 friction and wear tester, the friction and wear characteristics of slipper pair material in hydraulic component were investigated, and the friction coeficient-speed curves in the different pressures were got, as well as the wear rate-speed curves. The worn surface morphology of pin specimen was photographed by SEM, and the formation mechanism of the worn surface was analyzed. The results suggested that: friction coefficient and wear rate would have a jump when the scuffing occurred, the friction and wear characteristics would be affected by the interaction of pressure (P) and speed (V) . The PV characteristic restricted the correlation between working pressure and speed.

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The Relationship Between Hearing Loss Self-Management and Hearing Aid Benefit and Satisfaction

American Journal of Audiology ◽

10.1044/2018_aja-18-0130 ◽

2019 ◽

Vol 28 (2) ◽

pp. 274-284 ◽

Cited By ~ 6

Author(s):

Elizabeth Convery ◽

Gitte Keidser ◽

Louise Hickson ◽

Carly Meyer

Keyword(s):

Decision Making ◽

Hearing Loss ◽

Hearing Aids ◽

Clinical Decision Making ◽

Hearing Aid ◽

Well Being ◽

Self Report ◽

Self Management ◽

Hearing Aid Benefit ◽

The Relationship

Purpose Hearing loss self-management refers to the knowledge and skills people use to manage the effects of hearing loss on all aspects of their daily lives. The purpose of this study was to investigate the relationship between self-reported hearing loss self-management and hearing aid benefit and satisfaction. Method Thirty-seven adults with hearing loss, all of whom were current users of bilateral hearing aids, participated in this observational study. The participants completed self-report inventories probing their hearing loss self-management and hearing aid benefit and satisfaction. Correlation analysis was used to investigate the relationship between individual domains of hearing loss self-management and hearing aid benefit and satisfaction. Results Participants who reported better self-management of the effects of their hearing loss on their emotional well-being and social participation were more likely to report less aided listening difficulty in noisy and reverberant environments and greater satisfaction with the effect of their hearing aids on their self-image. Participants who reported better self-management in the areas of adhering to treatment, participating in shared decision making, accessing services and resources, attending appointments, and monitoring for changes in their hearing and functional status were more likely to report greater satisfaction with the sound quality and performance of their hearing aids. Conclusion Study findings highlight the potential for using information about a patient's hearing loss self-management in different domains as part of clinical decision making and management planning.

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Comparison of In-the-Ear and Over-the-Ear Hearing Aid Fittings

Journal of Speech and Hearing Disorders ◽

10.1044/jshd.5104.362 ◽

1986 ◽

Vol 51 (4) ◽

pp. 362-369 ◽

Cited By ~ 4

Author(s):

Donna M. Risberg ◽

Robyn M. Cox

Keyword(s):

Hearing Aids ◽

High Frequency ◽

Comparative Evaluation ◽

Speech Intelligibility ◽

Hearing Aid ◽

Hearing Aid Fitting ◽

The Difference ◽

Functional Gain ◽

The Relationship

A custom in-the-ear (ITE) hearing aid fitting was compared to two over-the-ear (OTE) hearing aid fittings for each of 9 subjects with mild to moderately severe hearing losses. Speech intelligibility via the three instruments was compared using the Speech Intelligibility Rating (SIR) test. The relationship between functional gain and coupler gain was compared for the ITE and the higher rated OTE instruments. The difference in input received at the microphone locations of the two types of hearing aids was measured for 10 different subjects and compared to the functional gain data. It was concluded that (a) for persons with mild to moderately severe hearing losses, appropriately adjusted custom ITE fittings typically yield speech intelligibility that is equal to the better OTE fitting identified in a comparative evaluation; and (b) gain prescriptions for ITE hearing aids should be adjusted to account for the high-frequency emphasis associated with in-the-concha microphone placement.

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Wear and Friction Characteristics of 65Mn Steel for Spike-Tooth Harrow

Coatings ◽

10.3390/coatings11030319 ◽

2021 ◽

Vol 11 (3) ◽

pp. 319

Author(s):

Zhiguo Lu ◽

Chuanyu Du ◽

Qingcai Chen ◽

Tianying Niu ◽

Na Wang ◽

...

Keyword(s):

Friction And Wear ◽

Working Environment ◽

Manganese Steel ◽

Wear Loss ◽

Variable Parameters ◽

Wear Characteristics ◽

Before And After ◽

Set Up ◽

Worn Surface ◽

Friction And Wear Characteristics

The friction and wear characteristics of spike-tooth material (65Mn steel) of Spike-Tooth Harrow in a two-stage peanut harvester were studied in this paper. The friction and wear tests of pin and disc on 65 manganese steel were carried out on the tribometer, then the wear loss and the friction coefficient were studied. The wear loss of the pin was acquired by calculating the mass of the pin before and after the experiment using an electronic balance. According to the actual working environment of peanut spring-finger, four variable parameters are set up: load, speed, soil moisture and soil type. The friction and wear characteristics of pins were studied under different loads, speeds and different soil environments. After wearing, the worn surface of the material was observed by scanning microscope and the wear mechanism was studied. The experimental results show that the wear of the pin increases with the increase of load and decreases with the increase of rotational speed in the same rotation number. Especially in the case of the sandy soil with 20% in moisture, a maximum wear loss of the pin is achieved.

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Tribological Behavior of Carbon Nanotubes as an Additive on Lithium Grease

Journal of Tribology ◽

10.1115/1.4028225 ◽

2014 ◽

Vol 137 (1) ◽

Cited By ~ 49

Author(s):

Alaa Mohamed ◽

T. A. Osman ◽

A. Khattab ◽

M. Zaki

Keyword(s):

Carbon Nanotubes ◽

Arc Discharge ◽

Average Diameter ◽

Friction Reduction ◽

Lithium Grease ◽

X Ray ◽

Transmission Electron ◽

Boundary Film ◽

Load Carrying ◽

Worn Surface

Carbon nanotubes (CNTs) with 10 nm average diameter and 5 μm in length were synthesized by electric arc discharge. The morphology and structure of CNTs were characterized by high resolution transmission electron microscopy (HRTEM) and X-ray powder diffraction. The tribological properties of CNTs as an additive on lithium grease were evaluated with a four ball tester. The results show that the grease with CNTs exhibit good performance in antiwear (AW) and decrease the wear scare diameter (WSD) about 63%, decrease friction reduction about 81.5%, and increase the extreme pressure (EP) properties and load carrying capacity about 52% with only 1% wt. of CNTs added to lithium grease. The action mechanism was estimated through analysis of the worn surface with a scanning electron microscope (SEM) and energy dispersive X-ray (EDX). The results indicate that a boundary film mainly composed of CNTs, Cr, iron oxide, and other organic compounds was formed on the worn surface during the friction process.

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Investigation of the causes of damage to freight cars during disbanding on non-mechanized sorting slides and development of measures to prevent them

Herald of the Ural State University of Railway Transport ◽

10.20291/2079-0392-2021-2-4-13 ◽

2021 ◽

pp. 4-13

Author(s):

S. V. Tankeev ◽

◽

A. E. Kolodin ◽

V. B. Sverdlov ◽

A. V. Nazarov ◽

...

Keyword(s):

Low Power ◽

Coefficient Of Friction ◽

Damage Assessment ◽

Laboratory Tests ◽

Rolling Stock ◽

Third Body ◽

Normative Documents ◽

The Coefficient Of Friction ◽

Loading And Unloading ◽

The Relationship

The damage assessment of freight cars during shunting and loading and unloading operations was made. The need to review the normative documents regulating the relationship between the owners of rolling stock, owners of non-public tracks and the carrier is noted. The reasons for formation of damage on the wheel pairs of freight cars when disbanding on low-power sorting slides are considered. The conditions for ensuring the deceleration of detachments on non-mechanized sorting slides without damaging the wheels are determined. The analysis of methods for ensuring braking on low-power slides is carried out. A method was chosen to ensure the wheel set rotation by introducing a third body between the rubbing surfaces during the braking of cars, which will take over a part of the resulting heat flow, reducing the temperature and increasing the coefficient of friction in the «wheel-rail» contact zone. A method is proposed to provide braking on the non-mechanized sorting slide during shoe braking by applying a friction compound to a non-working rail. Laboratory tests were carried out, which showed that the introduction of a friction additive can achieve the necessary coefficient of friction to comply with the standard parameters of deceleration of the car in the braking zone.

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Sliding wear characteristics of a-C:H:SiOx coatings

Journal of Tribology ◽

10.1115/1.4052940 ◽

2021 ◽

pp. 1-27

Author(s):

Alexander Grenadyorov ◽

Andrey Solovyev ◽

Konstantin Oskomov

Keyword(s):

Friction Coefficient ◽

Wear Rate ◽

Chemical Vapor ◽

Indentation Load ◽

Sliding Speed ◽

Carbon Coatings ◽

Wear Characteristics ◽

Load Increase ◽

Speed Up ◽

Polymeric Carbon

Abstract The paper presents the experimental study of the friction and wear characteristics of amorphous carbon coating containing hydrogen and SiOx (a-C:H:SiOx) deposited onto WC-8Co cemented carbide substrates. A 5 μm thick a-C:H:SiOx coating was fabricated using plasma-assisted chemical vapor deposition. The tribological properties of the a-C:H:SiOx coating sliding in contact with WC–8Co, ZrO2, SiC, Si3N4 counter bodies, are examined using the ball-on-disc method at different normal loads and sliding speeds. Tribology testing shows that the minimum values of the friction coefficient (0.044) and the wear rate (9.3×10−8 mm3/Nm) are observed when using a counter body made of silicon nitride at a 5 N indentation load. The load increase from 5 to 12 N raises the friction coefficient up to 0.083 and the wear rate up to 46×10−8 mm3/Nm. When the sliding speed reaches its critical value, the coating friction provides the transition from sp3 hybridized to sp2 hybridized and polymeric carbon, which is accompanied by the reduction in the friction coefficient. The a-C:H:SiOx coating provides an increase in the critical sliding speed up to 50–75 mm/s, which exceeds that of non-alloyed (a-C and a-C:H) diamond-like carbon coatings as a result of doping by silicon and oxygen.

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Wear characteristics of additively manufactured AlSi10Mg against EN-31 and silicon carbide abrasive sheet counter bodies using box Behnken design approach

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications ◽

10.1177/14644207211057002 ◽

2021 ◽

pp. 146442072110570

Author(s):

Raj Mohan Radhakrishnan ◽

Venkatraman Ramamoorthi ◽

Raghuraman Srinivasan

Keyword(s):

Silicon Carbide ◽

Wear Rate ◽

Weight Ratio ◽

High Strength ◽

Design Approach ◽

Box Behnken Design ◽

Wear Characteristics ◽

Testing Facility ◽

En 31 ◽

Sliding Distance

High strength-to-weight ratio materials are used in the automotive and aerospace industries, and AlSi10Mg is suitable for those applications. The research aims to compare and investigate the wear characteristics of selective laser melted AlSi10Mg pin against two counter bodies, EN-31 hardened steel, and silicon carbide abrasive sheet. The wear rate of additively manufactured AlSi10Mg pin at 0° building orientation was investigated using the box Behnken design approach to identify the suitable wear parameters with the pin on the disc testing facility. Based on analysis of variance, the interaction of load with sliding distance significantly influenced the wear rate of AlSi10Mg in both counter body cases. The adhesion and abrasion wear mechanism were observed in AlSi10Mg with EN-31 and silicon carbide abrasive sheet, respectively. The findings reveal the effect of two counter bodies on the SLMed AlSi10Mg wear phenomenon. Finally, severe wear was observed in the AlSi10Mg pin against the silicon carbide counter body.

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