Pub Date : 2024-07-01DOI: 10.21608/jest.2024.296433.1088
Naguib G. Yakoub
Recent years have witnessed an increasing amount of attention coming to triboelectric generators (TEGs) as a means of harvesting energy from various sources, such as mechanical vibrations, wind, and even human motion. The ability to automatically convert mechanical energy into electrical energy without requiring external power sources, which makes them easily applied. Due to this quality, TEGs have many applications, like self-powered devices, wireless sensors, and renewable energy systems. In TEGs, a triboelectric material gives off electrical charges upon contact with another material. Such material features as electrical conductivity and dielectric constant play a decisive role in TEG efficiency. Among the research projects on increasing triboelectric properties, the use of nano-additives is one of the techniques extensively studied. In this research, the triboelectric characteristics of the polymer nanocomposites that are reinforced with multi-walled carbon nanotubes (MWCNT), silica (SiO 2 ), alumina (Al 2 O 3 ), or a blend of them are studied when they are used as tribo-materials. The above dielectric nanoparticles can be added to modify the dielectric constant of the composite, which influences the triboelectric effect. Reinforcement concentration and rubbing time are adjusted in different ways and impact the output voltage. This study aims to uncover the possibility of using nano-reinforced polymers in TEG and other devices based on material triboelectricity.
{"title":"Nano-Enhanced Triboelectric Generators: Investigating Additive Effects on Output Voltage","authors":"Naguib G. Yakoub","doi":"10.21608/jest.2024.296433.1088","DOIUrl":"https://doi.org/10.21608/jest.2024.296433.1088","url":null,"abstract":"Recent years have witnessed an increasing amount of attention coming to triboelectric generators (TEGs) as a means of harvesting energy from various sources, such as mechanical vibrations, wind, and even human motion. The ability to automatically convert mechanical energy into electrical energy without requiring external power sources, which makes them easily applied. Due to this quality, TEGs have many applications, like self-powered devices, wireless sensors, and renewable energy systems. In TEGs, a triboelectric material gives off electrical charges upon contact with another material. Such material features as electrical conductivity and dielectric constant play a decisive role in TEG efficiency. Among the research projects on increasing triboelectric properties, the use of nano-additives is one of the techniques extensively studied. In this research, the triboelectric characteristics of the polymer nanocomposites that are reinforced with multi-walled carbon nanotubes (MWCNT), silica (SiO 2 ), alumina (Al 2 O 3 ), or a blend of them are studied when they are used as tribo-materials. The above dielectric nanoparticles can be added to modify the dielectric constant of the composite, which influences the triboelectric effect. Reinforcement concentration and rubbing time are adjusted in different ways and impact the output voltage. This study aims to uncover the possibility of using nano-reinforced polymers in TEG and other devices based on material triboelectricity.","PeriodicalId":212154,"journal":{"name":"Journal of the Egyptian Society of Tribology","volume":"3 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141715811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-01DOI: 10.21608/jest.2024.366461
A. S. Ali, A. M. Al-Kabbany, Zeinab A. H., W. Y. Ali, A. K. Ameer
. ABSTRACT The present work aims to decrease the friction coefficient displayed by the sliding polymeric composites on steel surface by filling the polymeric composites by conductive materials in order to decrease the resultant electrostatic charge (ESC) that increased the attraction between the two sliding surfaces. Experiments have been carried out to investigate the influence of filling the polymeric composites consisting of PMMA and PE by electrically conductive materials such as copper, aluminum, carbon fibers and carbon nanotubes on the friction coefficient when slid on bearing steel sphere at dry sliding conditions. It was found that PE gained negative charge during friction against steel that at the same time gained positive charge, while PMMA acquired positive charge when slid on steel that got negative one. The resultant charge gained by composites surface would be minimum. The positive and negative charges conducted into steel surface became neutralized if the two different charges are equal. The addition of sand particles into the composites aimed to enhance the wear resistance but it increased the friction coefficient. To overcome that behavior, different conductive materials were added, where carbon fibers experienced the best performance by reducing friction coefficient through decreasing ESC by conducting the different charges to each other.
.摘要 本研究旨在通过在聚合物复合材料中填充导电材料，降低聚合物复合材料在钢表面滑动时显示的摩擦系数，从而减少增加两个滑动表面之间吸引力的静电荷（ESC）。实验研究了在由 PMMA 和 PE 组成的聚合物复合材料中填充导电材料（如铜、铝、碳纤维和碳纳米管）对在干燥滑动条件下轴承钢球上滑动时摩擦系数的影响。研究发现，聚乙烯在与钢摩擦时获得负电荷，同时获得正电荷，而 PMMA 在钢上滑动时获得正电荷，同时获得负电荷。因此，复合材料表面获得的电荷最少。如果两种不同的电荷相等，传导到钢表面的正负电荷就会中和。在复合材料中添加砂粒的目的是为了提高耐磨性，但这会增加摩擦系数。为了克服这种现象，添加了不同的导电材料，其中碳纤维的性能最好，它通过不同电荷之间的相互传导，降低了静电荷，从而降低了摩擦系数。
{"title":"ROLE OF TRIBOELECTRIFICATION IN THE FRICTION OF SLIDING SURFACES","authors":"A. S. Ali, A. M. Al-Kabbany, Zeinab A. H., W. Y. Ali, A. K. Ameer","doi":"10.21608/jest.2024.366461","DOIUrl":"https://doi.org/10.21608/jest.2024.366461","url":null,"abstract":". ABSTRACT The present work aims to decrease the friction coefficient displayed by the sliding polymeric composites on steel surface by filling the polymeric composites by conductive materials in order to decrease the resultant electrostatic charge (ESC) that increased the attraction between the two sliding surfaces. Experiments have been carried out to investigate the influence of filling the polymeric composites consisting of PMMA and PE by electrically conductive materials such as copper, aluminum, carbon fibers and carbon nanotubes on the friction coefficient when slid on bearing steel sphere at dry sliding conditions. It was found that PE gained negative charge during friction against steel that at the same time gained positive charge, while PMMA acquired positive charge when slid on steel that got negative one. The resultant charge gained by composites surface would be minimum. The positive and negative charges conducted into steel surface became neutralized if the two different charges are equal. The addition of sand particles into the composites aimed to enhance the wear resistance but it increased the friction coefficient. To overcome that behavior, different conductive materials were added, where carbon fibers experienced the best performance by reducing friction coefficient through decreasing ESC by conducting the different charges to each other.","PeriodicalId":212154,"journal":{"name":"Journal of the Egyptian Society of Tribology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141705901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-01DOI: 10.21608/jest.2024.302696.1091
Mohamed Ahmed Ramadan, M. Maher, H. Mansour, W. Y. Ali
One of the main causes of mechanical parts failure is wear and friction between bearing surfaces. There is a lot of interest in the search for novel additives with excellent tribological characteristics. During this paper, the friction and wear of steel surfaces are discussed. zinc sulphide nano particles dispersing paraffin oil were used as lubricating substance. ZnS addition is aimed to reduce the impact friction between metal elements, on friction coefficient and wear of steel test specimens. The experiment was conducted using a cross-pin tester. The device consists, mainly, of rotating and stationary pins of 18 mm diameter and 130 mm long. (10, 15 and 20 N) normal loads are applied by means of weights attached to a loading lever. The rotating specimens are oiled with several percentage of zinc sulphide nano-additives (0, 0.2, 0.4, 0.6, 0.8, 1.0 wt. %) dispersing in paraffin base oil before the test and further oil is carried out every 30 sec. during the test. The test time is 5 min. The friction force is measured via a digital screen that connects to the load cell. Under an optical microscope, the scar's diameter is measured to indicate wear, and the coefficient of friction is computed by dividing the friction force by the normal load. Experiments were carried out at 25 °C using parrafin based oil dispersed by the solid additives of zinc sulphide nano particles. Experimental results show that 0.4 wt. % Zinc sulphide nano filler added to paraffin oil gives the best anti-friction and wear resistance performance.
{"title":"IMPROVING THE TRIBOLOGICAL PROPERTIES OF THE LUBRICANT USING ZnS NANOPARTICLES AS LUBRICANT ADDITIVES","authors":"Mohamed Ahmed Ramadan, M. Maher, H. Mansour, W. Y. Ali","doi":"10.21608/jest.2024.302696.1091","DOIUrl":"https://doi.org/10.21608/jest.2024.302696.1091","url":null,"abstract":"One of the main causes of mechanical parts failure is wear and friction between bearing surfaces. There is a lot of interest in the search for novel additives with excellent tribological characteristics. During this paper, the friction and wear of steel surfaces are discussed. zinc sulphide nano particles dispersing paraffin oil were used as lubricating substance. ZnS addition is aimed to reduce the impact friction between metal elements, on friction coefficient and wear of steel test specimens. The experiment was conducted using a cross-pin tester. The device consists, mainly, of rotating and stationary pins of 18 mm diameter and 130 mm long. (10, 15 and 20 N) normal loads are applied by means of weights attached to a loading lever. The rotating specimens are oiled with several percentage of zinc sulphide nano-additives (0, 0.2, 0.4, 0.6, 0.8, 1.0 wt. %) dispersing in paraffin base oil before the test and further oil is carried out every 30 sec. during the test. The test time is 5 min. The friction force is measured via a digital screen that connects to the load cell. Under an optical microscope, the scar's diameter is measured to indicate wear, and the coefficient of friction is computed by dividing the friction force by the normal load. Experiments were carried out at 25 °C using parrafin based oil dispersed by the solid additives of zinc sulphide nano particles. Experimental results show that 0.4 wt. % Zinc sulphide nano filler added to paraffin oil gives the best anti-friction and wear resistance performance.","PeriodicalId":212154,"journal":{"name":"Journal of the Egyptian Society of Tribology","volume":"24 S10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141713789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-01DOI: 10.21608/jest.2024.366956
A. M. Al-Kabbany, Zeinab A. H., W. Y. Ali
Triboelectric nanogenerators (TENGs) have emerged as a possible solution to many problems of our modern world by satisfying the need for self-powered sensors and new methods of energy harvesting. One of the applications of TENGs as self-powered sensors is as pressure sensors. This can be done by making a TENG with only one electrode connected to a dielectric. This paper proposes a method of using TENG-based Kapton pressure sensors in order to make a self-powered chess board with move recognition capabilities. It was found that the voltage generated by the sensor at contact increased with increasing the placing force of a wooden cube (simulating a chess piece) on it. However, the voltage generated at separation did not increase with the placing force. It was also found that voltage always increased with the resistance between the electrode and the ground in a resistance range of 0.33 MΩ to 50 MΩ. Current usually increased with resistance at first then stabilized at some point. A chess board column was then created using 8 pressure sensors connected to each other via resistances. It was found that the voltage between the chess board column and the ground decreased as the square number on which the wooden cube was placed or removed from increased. Showing that this is a viable method of monitoring movements across this column.
三电纳米发电机（TENGs）满足了人们对自供电传感器和新的能量收集方法的需求，成为解决现代世界许多问题的可能方案。TENG 作为自供电传感器的应用之一是作为压力传感器。这可以通过制作只有一个电极与电介质相连的 TENG 来实现。本文提出了一种使用基于 TENG 的 Kapton 压力传感器的方法，以制作具有移动识别功能的自供电国际象棋棋盘。研究发现，随着木质立方体（模拟棋子）在传感器上的放置力增加，传感器在接触时产生的电压也随之增加。然而，分离时产生的电压并不随放置力的增加而增加。研究还发现，在 0.33 MΩ 至 50 MΩ 的电阻范围内，电压总是随着电极与地面之间电阻的增加而增加。电流起初通常会随着电阻的增大而增大，然后在某一时刻趋于稳定。然后，利用 8 个压力传感器通过电阻相互连接，创建了一个棋盘式圆柱。结果发现，随着放置或移除木立方体的方格数增加，棋盘柱与地面之间的电压也随之降低。这表明这是一种监测棋盘柱移动的可行方法。
{"title":"DEVELOPMENT OF A CHESS BOARD WITH SELF-POWERED MOVE RECOGNITION","authors":"A. M. Al-Kabbany, Zeinab A. H., W. Y. Ali","doi":"10.21608/jest.2024.366956","DOIUrl":"https://doi.org/10.21608/jest.2024.366956","url":null,"abstract":"Triboelectric nanogenerators (TENGs) have emerged as a possible solution to many problems of our modern world by satisfying the need for self-powered sensors and new methods of energy harvesting. One of the applications of TENGs as self-powered sensors is as pressure sensors. This can be done by making a TENG with only one electrode connected to a dielectric. This paper proposes a method of using TENG-based Kapton pressure sensors in order to make a self-powered chess board with move recognition capabilities. It was found that the voltage generated by the sensor at contact increased with increasing the placing force of a wooden cube (simulating a chess piece) on it. However, the voltage generated at separation did not increase with the placing force. It was also found that voltage always increased with the resistance between the electrode and the ground in a resistance range of 0.33 MΩ to 50 MΩ. Current usually increased with resistance at first then stabilized at some point. A chess board column was then created using 8 pressure sensors connected to each other via resistances. It was found that the voltage between the chess board column and the ground decreased as the square number on which the wooden cube was placed or removed from increased. Showing that this is a viable method of monitoring movements across this column.","PeriodicalId":212154,"journal":{"name":"Journal of the Egyptian Society of Tribology","volume":"2 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141846564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-01DOI: 10.21608/jest.2024.366467
A. M. I. Abu-Oqail, Ahmed M. Elmashad, Mohamed N. El-Sheikh, Moustafa M. Mohamed, M. Hassan A. El-Sayed
.
.
{"title":"MECHANICAL AND TRIBOLOGICAL PERFORMANCE OF Al-x SiC COMPOSITES PRODUCED BY POWDER METALLURGY TECHNIQUE FOR THROTTLE VALVES APPLICATIONS","authors":"A. M. I. Abu-Oqail, Ahmed M. Elmashad, Mohamed N. El-Sheikh, Moustafa M. Mohamed, M. Hassan A. El-Sayed","doi":"10.21608/jest.2024.366467","DOIUrl":"https://doi.org/10.21608/jest.2024.366467","url":null,"abstract":".","PeriodicalId":212154,"journal":{"name":"Journal of the Egyptian Society of Tribology","volume":"10 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141705039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-01DOI: 10.21608/jest.2024.366462
A. M. Al-Kabbany, M. K. Mohamed, M. M. Youssef, Eyad M. A., W. Y. Ali
In the present work, the friction coefficient (µ) between bare foot and foot wearing socks sliding on insoles to facilitate the proper selection of the insole materials. In order to avoid car accidents, it is necessary that the value of friction coefficient between the surfaces of foot skin and insoles should be enough high to prevent foot slip on the braking pedal pad. When the foot slides on the insole to a certain distance for people wearing slipper, the risk of car accident is arising. Two types of natural leather and four types of polymeric insoles, used in manufacturing of shoes and slippers, were tested to determine friction coefficient between bare foot and the tested insoles The experiments revealed that µ decreased with increasing the normal load displayed. The sliding of bare foot against natural leather (I, II) insole showed relatively higher values than foot wearing sock. In addition, polymeric insole (III) experienced relatively higher µ compared to that observed for the natural leather. While insole (IV), bare foot displayed higher µ than foot wearing sock. As for insoles (V and VI) of rougher surfaces, significant increase in µ was observed compared to the insoles of smooth surfaces, where the values of µ can be considered quite good to guarantee to limit slip. Finally, it is proposed to roughen the insole surface to increase µ values.
{"title":"PROPER SELECTION OF FOOT INSOLE FOR SLIPPERS","authors":"A. M. Al-Kabbany, M. K. Mohamed, M. M. Youssef, Eyad M. A., W. Y. Ali","doi":"10.21608/jest.2024.366462","DOIUrl":"https://doi.org/10.21608/jest.2024.366462","url":null,"abstract":"In the present work, the friction coefficient (µ) between bare foot and foot wearing socks sliding on insoles to facilitate the proper selection of the insole materials. In order to avoid car accidents, it is necessary that the value of friction coefficient between the surfaces of foot skin and insoles should be enough high to prevent foot slip on the braking pedal pad. When the foot slides on the insole to a certain distance for people wearing slipper, the risk of car accident is arising. Two types of natural leather and four types of polymeric insoles, used in manufacturing of shoes and slippers, were tested to determine friction coefficient between bare foot and the tested insoles The experiments revealed that µ decreased with increasing the normal load displayed. The sliding of bare foot against natural leather (I, II) insole showed relatively higher values than foot wearing sock. In addition, polymeric insole (III) experienced relatively higher µ compared to that observed for the natural leather. While insole (IV), bare foot displayed higher µ than foot wearing sock. As for insoles (V and VI) of rougher surfaces, significant increase in µ was observed compared to the insoles of smooth surfaces, where the values of µ can be considered quite good to guarantee to limit slip. Finally, it is proposed to roughen the insole surface to increase µ values.","PeriodicalId":212154,"journal":{"name":"Journal of the Egyptian Society of Tribology","volume":"276 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141692198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-01DOI: 10.21608/jest.2024.366463
A. M. Al-Kabbany, M. K. Mohamed, Eyad M. A., M. M. Youssef, W. Y. Ali
In eye surgery, eye drapes are used to separate and protect the eye area during surgical operations and medical tests. They are often made of non-woven fabrics made of polypropylene (PP) and polyethylene (PE) film. They are sterile to prevent contact with unsterile surfaces and to maintain the sterility of surrounding surfaces and the medical equipment. The present work investigates the electrostatic charges (ESC) generated on the surface of the eye drapes and doctor gown during surgery when they touch each other. The experiments in the present work showed that it was found that at dry contact, the generated ESC significantly increased when the load increased. Because human skin of the patient is good conductor, ESC generated on eye drape was lower than that observed for doctor gown. Sliding of the gown on eye drape showed higher intensity of ESC compared to contact/separation. It was observed that water wet surfaces exhibited higher ESC values in both contact/separation and sliding accumulated on the surface of eye drape. As result of that, an electric field may be generated and disturb the performance of the electronic appliances used in surgery. Finally, it is recommended to replace latex gloves by PE ones.
{"title":"ELECTROSTATIC CHARGES GENERATED ON THE SURFACE OF EYE DRAPES DURING SURGERY","authors":"A. M. Al-Kabbany, M. K. Mohamed, Eyad M. A., M. M. Youssef, W. Y. Ali","doi":"10.21608/jest.2024.366463","DOIUrl":"https://doi.org/10.21608/jest.2024.366463","url":null,"abstract":"In eye surgery, eye drapes are used to separate and protect the eye area during surgical operations and medical tests. They are often made of non-woven fabrics made of polypropylene (PP) and polyethylene (PE) film. They are sterile to prevent contact with unsterile surfaces and to maintain the sterility of surrounding surfaces and the medical equipment. The present work investigates the electrostatic charges (ESC) generated on the surface of the eye drapes and doctor gown during surgery when they touch each other. The experiments in the present work showed that it was found that at dry contact, the generated ESC significantly increased when the load increased. Because human skin of the patient is good conductor, ESC generated on eye drape was lower than that observed for doctor gown. Sliding of the gown on eye drape showed higher intensity of ESC compared to contact/separation. It was observed that water wet surfaces exhibited higher ESC values in both contact/separation and sliding accumulated on the surface of eye drape. As result of that, an electric field may be generated and disturb the performance of the electronic appliances used in surgery. Finally, it is recommended to replace latex gloves by PE ones.","PeriodicalId":212154,"journal":{"name":"Journal of the Egyptian Society of Tribology","volume":"4 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141701502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-01DOI: 10.21608/jest.2024.366466
A. S. Ali, A. M. Al-Kabbany, Zeinab A. H., W. Y. Ali, K. M. Atia
The present study investigates friction and wear of polymeric composites by scratch test. Polymeric composites consisting of polymethyl methacrylate (PMMA) and polyethylene (PE) have been filled by sand, aluminum, copper, carbon fibers and carbon nanotubes. The tribological properties have been determined by scratch test. The experiments revealed that friction coefficient slightly increased up to maximum then decreased with increasing the applied load. Filling composites by sand increased friction coefficient and decreased wear, while copper and aluminum as fillers did not alter frictional behavior but they increased wear. It was observed that addition of carbon fibers and carbon nanotubes drastically decreased friction coefficient and wear. It seems that they provided low shear layer in the in the contact surface of the tested composites that decreased friction. Besides, their lubricating action decreased wear.
{"title":"FRICTION AND WEAR OF SCRATCHED POLYMERIC COMPOSITES","authors":"A. S. Ali, A. M. Al-Kabbany, Zeinab A. H., W. Y. Ali, K. M. Atia","doi":"10.21608/jest.2024.366466","DOIUrl":"https://doi.org/10.21608/jest.2024.366466","url":null,"abstract":"The present study investigates friction and wear of polymeric composites by scratch test. Polymeric composites consisting of polymethyl methacrylate (PMMA) and polyethylene (PE) have been filled by sand, aluminum, copper, carbon fibers and carbon nanotubes. The tribological properties have been determined by scratch test. The experiments revealed that friction coefficient slightly increased up to maximum then decreased with increasing the applied load. Filling composites by sand increased friction coefficient and decreased wear, while copper and aluminum as fillers did not alter frictional behavior but they increased wear. It was observed that addition of carbon fibers and carbon nanotubes drastically decreased friction coefficient and wear. It seems that they provided low shear layer in the in the contact surface of the tested composites that decreased friction. Besides, their lubricating action decreased wear.","PeriodicalId":212154,"journal":{"name":"Journal of the Egyptian Society of Tribology","volume":"84 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141712057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-01DOI: 10.21608/jest.2024.366468
Mohamed M. Hedaya, Mohamed Elhadidi, Taher Elyazied, Mahmoud Z. Ibrahim
Energy harvesting is an emerging topic recently. This harvested energy is used to operate wireless sensors for different industrial monitoring and automation. To maximize the harvested energy in spinning systems, the harvester should vibrate at resonance for different spinning frequencies which can be achieved by active fitting. In this research, a novel methodology was developed by actively customizing the length of vibrating element beam to manipulate its natural frequency according to the spinning frequency. Different models were investigated numerically and experimentally to verify the proposed methodology. COMSOL Multiphysics software V5.1 was used to develop the numerical model, then and tip deformation and voltage difference results were benchmarked. The numerical model was verified experimentally by attaching a piezoelectric MIDE PPA 1021 which its vibrating length was varied by changing the supporting length from 0 mm to 12 mm to a spinning object having variable frequency from 0-200 Hz. It is found that the MIDE PPA 1021 beam vibrated at its resonance throughout the specified spinning frequencies. The proposed harvester can be applied in battery-free sensors being used in automotives, wind-mills blades, and rotating machinery.
{"title":"ENERGY HARVESTING AND OPTIMIZATION USING ACTIVE RESONANCE FITTING","authors":"Mohamed M. Hedaya, Mohamed Elhadidi, Taher Elyazied, Mahmoud Z. Ibrahim","doi":"10.21608/jest.2024.366468","DOIUrl":"https://doi.org/10.21608/jest.2024.366468","url":null,"abstract":"Energy harvesting is an emerging topic recently. This harvested energy is used to operate wireless sensors for different industrial monitoring and automation. To maximize the harvested energy in spinning systems, the harvester should vibrate at resonance for different spinning frequencies which can be achieved by active fitting. In this research, a novel methodology was developed by actively customizing the length of vibrating element beam to manipulate its natural frequency according to the spinning frequency. Different models were investigated numerically and experimentally to verify the proposed methodology. COMSOL Multiphysics software V5.1 was used to develop the numerical model, then and tip deformation and voltage difference results were benchmarked. The numerical model was verified experimentally by attaching a piezoelectric MIDE PPA 1021 which its vibrating length was varied by changing the supporting length from 0 mm to 12 mm to a spinning object having variable frequency from 0-200 Hz. It is found that the MIDE PPA 1021 beam vibrated at its resonance throughout the specified spinning frequencies. The proposed harvester can be applied in battery-free sensors being used in automotives, wind-mills blades, and rotating machinery.","PeriodicalId":212154,"journal":{"name":"Journal of the Egyptian Society of Tribology","volume":"52 39","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141690027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-01-07DOI: 10.21608/jest.2024.334765
H. A. Omran, M. M. Mahmoud, S. Z. Al-Abdeen, A. A. Mazen
Heat treatment is one of the most common processes done to metals due to its versatility. It can be used to make a material harder or more machinable according to the type of treatment done. Tool steel and mold steel are usually required to be machinable and need to be hard during operation. Which makes them some of the most commonly heat-treated materials. This study investigates the tribological properties of Hot-work tool steel W302, cold-work tool steel K110, and plastic mold steel M303. It was found that annealing all 3 metals caused the metal to have the highest values of material loss due to wear and the highest friction coefficient. The lowest value for the coefficient of friction for the cold-work tool steel K110 was for the hardened-tempered sample and was the as-received sample for the M303 steel. Hardened-tempered samples across the three tested metals had the highest values of hardness, increasing the hardness of the W302, K110, and M303 by 43.81 %, 126.6 %, and 70.78 % respectively and thus had the lowest values of weight loss due to wear.
{"title":"EFFECT OF HEAT TREATMENT ON THE TRIBOLOGICAL PROPERTIES OF TOOL STEEL AND MOLD STEEL","authors":"H. A. Omran, M. M. Mahmoud, S. Z. Al-Abdeen, A. A. Mazen","doi":"10.21608/jest.2024.334765","DOIUrl":"https://doi.org/10.21608/jest.2024.334765","url":null,"abstract":"Heat treatment is one of the most common processes done to metals due to its versatility. It can be used to make a material harder or more machinable according to the type of treatment done. Tool steel and mold steel are usually required to be machinable and need to be hard during operation. Which makes them some of the most commonly heat-treated materials. This study investigates the tribological properties of Hot-work tool steel W302, cold-work tool steel K110, and plastic mold steel M303. It was found that annealing all 3 metals caused the metal to have the highest values of material loss due to wear and the highest friction coefficient. The lowest value for the coefficient of friction for the cold-work tool steel K110 was for the hardened-tempered sample and was the as-received sample for the M303 steel. Hardened-tempered samples across the three tested metals had the highest values of hardness, increasing the hardness of the W302, K110, and M303 by 43.81 %, 126.6 %, and 70.78 % respectively and thus had the lowest values of weight loss due to wear.","PeriodicalId":212154,"journal":{"name":"Journal of the Egyptian Society of Tribology","volume":"47 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139535962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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