AbstractThe aim of the present work was to investigate the tribological behavior for each component of vein-bionic textured cylindrical roller thrust bearings and reveal the influence of chief vein on tribological performance of bearing system under starved lubrication. Two types of vein-bionic texture patterns derived from five kinds of leaves namely Forsythia, Clausena lansium, Ash, Pipal, and Apricot were prepared on the raceway of the shaft washer of cylindrical roller thrust bearings (CRTBs) by a fiber laser marking system. A vertical universal wear test rig with a customized tribo-pair was used to measure the coefficients of friction (COFs) of bearings under starved lubrication. The wear losses of shaft washer, cage, and housing washer were obtained, respectively, and the worn surfaces were characterized. The results show that the total wear losses for CRTB system were dominated by losses of the cage under starved lubrication. The lubricant impacted by different vein-bionic textures play a more significant role in generating the preferable nylon film instead of the amount of nylon powder. Additionally, larger area nylon film was observed for vein-bionic textures with no-chief vein, which correlates with larger wear losses for whole CRTB system. Due to the excellent secondary lubrication effect generated by chief vein, the nylon film with enhanced friction-reduction property can easily obtained, and the mass losses for bearing system were greatly decreased under starved lubrication.Keywords: Rolling element bearingVein-bionic textureLaser surface texturingTribological behaviorStarved lubricationDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.
{"title":"Tribological Behavior for Vein-bionic Textured Cylindrical Roller Thrust Bearing System under Starved Lubrication","authors":"Chao Zhao, Ruxin Liu, Kaiqing Qiao, Lixia Ying, Zhiyong Wang, Jiashuai Hu, Risheng Long","doi":"10.1080/10402004.2023.2275687","DOIUrl":"https://doi.org/10.1080/10402004.2023.2275687","url":null,"abstract":"AbstractThe aim of the present work was to investigate the tribological behavior for each component of vein-bionic textured cylindrical roller thrust bearings and reveal the influence of chief vein on tribological performance of bearing system under starved lubrication. Two types of vein-bionic texture patterns derived from five kinds of leaves namely Forsythia, Clausena lansium, Ash, Pipal, and Apricot were prepared on the raceway of the shaft washer of cylindrical roller thrust bearings (CRTBs) by a fiber laser marking system. A vertical universal wear test rig with a customized tribo-pair was used to measure the coefficients of friction (COFs) of bearings under starved lubrication. The wear losses of shaft washer, cage, and housing washer were obtained, respectively, and the worn surfaces were characterized. The results show that the total wear losses for CRTB system were dominated by losses of the cage under starved lubrication. The lubricant impacted by different vein-bionic textures play a more significant role in generating the preferable nylon film instead of the amount of nylon powder. Additionally, larger area nylon film was observed for vein-bionic textures with no-chief vein, which correlates with larger wear losses for whole CRTB system. Due to the excellent secondary lubrication effect generated by chief vein, the nylon film with enhanced friction-reduction property can easily obtained, and the mass losses for bearing system were greatly decreased under starved lubrication.Keywords: Rolling element bearingVein-bionic textureLaser surface texturingTribological behaviorStarved lubricationDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.","PeriodicalId":23315,"journal":{"name":"Tribology Transactions","volume":"32 23","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135973265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ABSTRACTFretting wear occurring on the roller and raceway of rolling bearings is prone to reduce the reliability of bearings. In this study, fine particle bombardment (FPB) under different air pressures (0.3 and 0.6MPa) was performed on GCr15 bearing steel, and the microstructure and fretting wear properties of GCr15 bearing steel modified by FPB were systematically investigated. The results show that the surface structure of the samples undergone severe plastic deformation, which led to surface grain refinement and increased in dislocation density. Besides, the martensite bundle size decreased, and the density of LAGBs and HAGBs increased. Moreover, the FPB improved the microhardness and thickness of the deformed layer. The enhancement was positively correlated with the air pressure of FPB. Compared with the untreated sample, the wear volume of the FPB samples increased by 10.1% (0.3MPa) and 19.0% (0.6MPa), respectively. Therefore, the fretting wear resistance was significantly improved. The main wear mechanism changed from severe adhesive wear, abrasive wear, and fatigue wear to slight adhesive wear owing to the application of FPB.KEYWORD: Fine particle bombardment；GCr15；microstructure；fretting wearDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.
{"title":"Investigation on microstructure and fretting wear properties of GCr15 bearing steel modified by fine particle bombardment","authors":"Shuqi Li, Mingyuan Zhang, Dianxiu Xia, Shouren Wang, Yuquan Cai, Guyi Si, Yunhe Zhang, Zhengpeng Han, Xinhua Sun, Han Zhang, Jianqi Hu","doi":"10.1080/10402004.2023.2277278","DOIUrl":"https://doi.org/10.1080/10402004.2023.2277278","url":null,"abstract":"ABSTRACTFretting wear occurring on the roller and raceway of rolling bearings is prone to reduce the reliability of bearings. In this study, fine particle bombardment (FPB) under different air pressures (0.3 and 0.6MPa) was performed on GCr15 bearing steel, and the microstructure and fretting wear properties of GCr15 bearing steel modified by FPB were systematically investigated. The results show that the surface structure of the samples undergone severe plastic deformation, which led to surface grain refinement and increased in dislocation density. Besides, the martensite bundle size decreased, and the density of LAGBs and HAGBs increased. Moreover, the FPB improved the microhardness and thickness of the deformed layer. The enhancement was positively correlated with the air pressure of FPB. Compared with the untreated sample, the wear volume of the FPB samples increased by 10.1% (0.3MPa) and 19.0% (0.6MPa), respectively. Therefore, the fretting wear resistance was significantly improved. The main wear mechanism changed from severe adhesive wear, abrasive wear, and fatigue wear to slight adhesive wear owing to the application of FPB.KEYWORD: Fine particle bombardment；GCr15；microstructure；fretting wearDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.","PeriodicalId":23315,"journal":{"name":"Tribology Transactions","volume":"57 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136023473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-25DOI: 10.1080/10402004.2023.2274869
Jiale Wei, Yaping Bai, Jianping Li, Yongchun Guo, Nan Li, Chongfeng Sun
Abstract For this study, Fe-25Mn-9Al-8Cr-1C-xMo alloys (x = 0, 0.1, 0.2, 0.3, 0.4 wt%) were prepared by mechanical alloying combined with vacuum hot-pressing sintering. The corresponding microstructure, mechanical properties, and friction and wear properties under different working conditions (dry friction, oil lubrication and sulfur-containing boundary lubrication) of materials were studied. The results show that the Fe-25Mn-9Al-8Cr-1C alloy is mainly composed of the austenite phase, Cr7C3 phase, and a small amount of a-Al2O3 phase. After adding Mo element, the Fe2MoC phase appears. With the increase of Mo content, the tensile strength and elongation of the alloys increase first and then decrease. In particular, when the Mo content is 0.3 wt%, an excellent combination of strength and toughness is obtained. The product of strength and elongation of the Fe-25Mn-9Al-8Cr-1C-0.3Mo alloy reaches a maximum value of 3.69 GPa·%, which is improved by 158.04% compared with the matrix alloys. With the increase of Mo content, the average friction coefficient and volume wear rate of the alloys show a trend of first decreasing and then increasing under different working conditions. Also, the average friction coefficient and volume wear rate of the alloy with 0.3 wt% Mo reach a minimum value, especially under the condition of sulfur-containing boundary lubrication. The average friction coefficient and volume wear rate of Fe-25Mn-9Al-8Cr-1C-0.3Mo alloy are 0.051 and 0.222 × 10−4 mm3·N−1·m−1, respectively, which are 40.69% and 46.38% lower than those of the matrix alloys.
{"title":"Effect of Mo content on friction and wear properties of Fe-Mn-Al-C alloys under different working conditions","authors":"Jiale Wei, Yaping Bai, Jianping Li, Yongchun Guo, Nan Li, Chongfeng Sun","doi":"10.1080/10402004.2023.2274869","DOIUrl":"https://doi.org/10.1080/10402004.2023.2274869","url":null,"abstract":"Abstract For this study, Fe-25Mn-9Al-8Cr-1C-xMo alloys (x = 0, 0.1, 0.2, 0.3, 0.4 wt%) were prepared by mechanical alloying combined with vacuum hot-pressing sintering. The corresponding microstructure, mechanical properties, and friction and wear properties under different working conditions (dry friction, oil lubrication and sulfur-containing boundary lubrication) of materials were studied. The results show that the Fe-25Mn-9Al-8Cr-1C alloy is mainly composed of the austenite phase, Cr7C3 phase, and a small amount of a-Al2O3 phase. After adding Mo element, the Fe2MoC phase appears. With the increase of Mo content, the tensile strength and elongation of the alloys increase first and then decrease. In particular, when the Mo content is 0.3 wt%, an excellent combination of strength and toughness is obtained. The product of strength and elongation of the Fe-25Mn-9Al-8Cr-1C-0.3Mo alloy reaches a maximum value of 3.69 GPa·%, which is improved by 158.04% compared with the matrix alloys. With the increase of Mo content, the average friction coefficient and volume wear rate of the alloys show a trend of first decreasing and then increasing under different working conditions. Also, the average friction coefficient and volume wear rate of the alloy with 0.3 wt% Mo reach a minimum value, especially under the condition of sulfur-containing boundary lubrication. The average friction coefficient and volume wear rate of Fe-25Mn-9Al-8Cr-1C-0.3Mo alloy are 0.051 and 0.222 × 10−4 mm3·N−1·m−1, respectively, which are 40.69% and 46.38% lower than those of the matrix alloys.","PeriodicalId":23315,"journal":{"name":"Tribology Transactions","volume":"61 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135170799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Thin film formation of lubricant plays a key role in supporting lubrication and abating wear. During cold rolling of steel, esters, or film formers in rolling oil play an important role in the mixed lubrication regime. The property of the lubricant holds the key to achieving the mean film thickness during the mixed lubrication regimen. Band formation in cold rolling is often related to inadequate acid pickling. During cold rolling operation, the film formation between asperities plays an important role in controlling friction and coil temperatures. A well formulated lubricant ensures smooth transition of lubrication throughout the range of roll bite temperature and also across the lubrication regimes. A sudden spike in coefficient of friction (CoF) can often lead to increased wear and abnormal increase in coil temperatures resulting in band formation. The study highlights degradation of oil sample leading to the problem and the role of key lubricant properties in esters in mitigating the problem.
{"title":"A novel approach to address brownish edge band in low alloy cold rolled steel used in Tin Plate","authors":"Subho Chakraborty, Suvendu Sekhar Giri, A.N Bhagat","doi":"10.1080/10402004.2023.2275686","DOIUrl":"https://doi.org/10.1080/10402004.2023.2275686","url":null,"abstract":"Abstract Thin film formation of lubricant plays a key role in supporting lubrication and abating wear. During cold rolling of steel, esters, or film formers in rolling oil play an important role in the mixed lubrication regime. The property of the lubricant holds the key to achieving the mean film thickness during the mixed lubrication regimen. Band formation in cold rolling is often related to inadequate acid pickling. During cold rolling operation, the film formation between asperities plays an important role in controlling friction and coil temperatures. A well formulated lubricant ensures smooth transition of lubrication throughout the range of roll bite temperature and also across the lubrication regimes. A sudden spike in coefficient of friction (CoF) can often lead to increased wear and abnormal increase in coil temperatures resulting in band formation. The study highlights degradation of oil sample leading to the problem and the role of key lubricant properties in esters in mitigating the problem.","PeriodicalId":23315,"journal":{"name":"Tribology Transactions","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135216611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract For this study, E690 steel claddings with different contents of TiC were prepared by laser cladding for revealing effects of TiC on microstructure, mechanical properties, and wear behavior of the cladded steel. The microstructure and mechanical properties of the cladded alloys were observed and measured. The wear resistance of the cladded alloys was tested using a ball-on-disc tribometer. The experimental results showed that TiC refined the grain of the cladded alloy obviously. However, excessive TiC could lead to the network-like distribution of submicro TiC particles in the claddings. The microhardness of the cladded alloy with 1% TiC increased to 418.5 ± 10.7 HV500, and yield strength and ultimate tensile strength (UTS) increased by 11% and 7% compared with those of the cladded alloy without TiC. Excessive TiC decreased the tensile properties to an obvious degree. The addition of TiC improved the wear resistance of the cladded alloy significantly. When normal loads were 5 N and 10 N, the cladded alloy with 5% TiC exhibited high wear resistance, and the wear rates decreased by 59% and 78% compared with those of the cladded alloy without TiC. However, when normal load was 20 N, the cladded alloy with 1% TiC possessed superior wear resistance, and its wear rate decreased by 81% compared with that of the cladded alloy without TiC. The main wear mechanism of the cladded alloys was abrasion wear when normal load was low, but serious plastic deformation played a role in the wear process when normal load was high.
{"title":"Effects of TiC on the microstructure, mechanical properties and wear behavior of E690 steel prepared by laser cladding","authors":"Qingtian Yang, Guohua Chen, Tong Li, Jiangwen Liu, Junfeng Gou, None Yongkang Zhang, Jinbao Guo, Guibin Tan, You Wang, Ruiyu Li","doi":"10.1080/10402004.2023.2275680","DOIUrl":"https://doi.org/10.1080/10402004.2023.2275680","url":null,"abstract":"Abstract For this study, E690 steel claddings with different contents of TiC were prepared by laser cladding for revealing effects of TiC on microstructure, mechanical properties, and wear behavior of the cladded steel. The microstructure and mechanical properties of the cladded alloys were observed and measured. The wear resistance of the cladded alloys was tested using a ball-on-disc tribometer. The experimental results showed that TiC refined the grain of the cladded alloy obviously. However, excessive TiC could lead to the network-like distribution of submicro TiC particles in the claddings. The microhardness of the cladded alloy with 1% TiC increased to 418.5 ± 10.7 HV500, and yield strength and ultimate tensile strength (UTS) increased by 11% and 7% compared with those of the cladded alloy without TiC. Excessive TiC decreased the tensile properties to an obvious degree. The addition of TiC improved the wear resistance of the cladded alloy significantly. When normal loads were 5 N and 10 N, the cladded alloy with 5% TiC exhibited high wear resistance, and the wear rates decreased by 59% and 78% compared with those of the cladded alloy without TiC. However, when normal load was 20 N, the cladded alloy with 1% TiC possessed superior wear resistance, and its wear rate decreased by 81% compared with that of the cladded alloy without TiC. The main wear mechanism of the cladded alloys was abrasion wear when normal load was low, but serious plastic deformation played a role in the wear process when normal load was high.","PeriodicalId":23315,"journal":{"name":"Tribology Transactions","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135217377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-18DOI: 10.1080/10402004.2023.2270652
Jian Liu, Zhen Yan, Junying Hao, Weimin Liu
ABSTRACTPFPE (Perfluoropolyether) oil possessing higher oxidation stability than hydrocarbon lubricant is combined with Ti:WS2 film to construct solid-liquid composite lubricating system. The results indicate that atomic oxygen (AO) irradiation generates some important effects for the Ti:WS2/PFPE composite lubricating system. With increase of irradiation dose, the molecule structure of PFPE oil occurs to carbon chain breakage and appears the obvious molecule cross-linking and polymerization. Meanwhile, Ti:WS2 film also is oxidized to different extent to form WO3. The changes in solid-liquid system resulted in the greatly different tribological properties of Ti:WS2/PFPE system. The friction coefficient of the system significantly increases in low-dose irradiation, while the value inversely sharply decreases in high-dose AO, which is related to the presence of WO3 and formed transfer film. Finally, the failure mechanism of Ti:WS2/PFPE system under AO irradiation was revealed.KEYWORDS: Solid-liquid lubricationPFPE oilAO irradiationTribological performanceFailure mechanismDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.
{"title":"Effect of irradiation dose on the structure and tribological performance of Ti:WS <sub>2</sub> /PFPE composite lubricating system in atomic oxygen environment","authors":"Jian Liu, Zhen Yan, Junying Hao, Weimin Liu","doi":"10.1080/10402004.2023.2270652","DOIUrl":"https://doi.org/10.1080/10402004.2023.2270652","url":null,"abstract":"ABSTRACTPFPE (Perfluoropolyether) oil possessing higher oxidation stability than hydrocarbon lubricant is combined with Ti:WS2 film to construct solid-liquid composite lubricating system. The results indicate that atomic oxygen (AO) irradiation generates some important effects for the Ti:WS2/PFPE composite lubricating system. With increase of irradiation dose, the molecule structure of PFPE oil occurs to carbon chain breakage and appears the obvious molecule cross-linking and polymerization. Meanwhile, Ti:WS2 film also is oxidized to different extent to form WO3. The changes in solid-liquid system resulted in the greatly different tribological properties of Ti:WS2/PFPE system. The friction coefficient of the system significantly increases in low-dose irradiation, while the value inversely sharply decreases in high-dose AO, which is related to the presence of WO3 and formed transfer film. Finally, the failure mechanism of Ti:WS2/PFPE system under AO irradiation was revealed.KEYWORDS: Solid-liquid lubricationPFPE oilAO irradiationTribological performanceFailure mechanismDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.","PeriodicalId":23315,"journal":{"name":"Tribology Transactions","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135887956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-17DOI: 10.1080/10402004.2023.2269242
Mohamed E. Haseeb, Rabab M. Nasser, Amal M. Nassar, Nehal S. Ahmed
AbstractThe failure of mineral oils to work in machinery and engines under intense pressure, heat, and corrosion has prompted researchers to consider the development of synthetic lubricating oils that are appropriate for these demanding conditions. This research was conducted to synthesize new esters by reaction of citric acids (CA) with mono-alcohols (hexanol, octanol, decanol and 2-ethylhexanol), then the products were reacted with propanoic acid, valeric acid, and octanoic acid separately using 1:1 molar ratio. The resulting esters were characterized using nuclear magnetic resonance spectroscopy (NMR), Fourier-transform infrared spectroscopy (FTIR), and thermal gravimetric analysis (TGA). The rheological properties were studied, and it was found that the prepared esters have high thermal stabilities as the degradation takes place in the range of 175ºC - 425ºC. The prepared esters show Newtonian behaviors as their viscosities do not change by changing shear rate. The physicochemical characteristic of prepared esters were also determined which showed improved low temperature properties (PP) -36ºC for ester (2R)-1,2-bis(2-ethylhexyl) 3-nonyl 2-(pentanoyloxy)propane-1,2,3-tricarboxylate (COEV) and viscosity index (VI) at 195 for ester (2R)-1-decyl 3-(2-ethylhexyl) 2-heptan-3-yl 2-(propionyloxy)propane-1,2,3-tricarboxylate (CDEP). The stabilities of the prepared esters were confirmed via the computational analysis and their stabilities were ranked as CDEP > COEP > COEO > COEV.Keywords: synthetic lubricantscitrate estersrheologyviscosity indexpour pointDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.
{"title":"Citric Acid-Based Esters as Potential Synthetic Lubricants: A Study of Their Synthesis, Rheological Properties and Thermal Stability","authors":"Mohamed E. Haseeb, Rabab M. Nasser, Amal M. Nassar, Nehal S. Ahmed","doi":"10.1080/10402004.2023.2269242","DOIUrl":"https://doi.org/10.1080/10402004.2023.2269242","url":null,"abstract":"AbstractThe failure of mineral oils to work in machinery and engines under intense pressure, heat, and corrosion has prompted researchers to consider the development of synthetic lubricating oils that are appropriate for these demanding conditions. This research was conducted to synthesize new esters by reaction of citric acids (CA) with mono-alcohols (hexanol, octanol, decanol and 2-ethylhexanol), then the products were reacted with propanoic acid, valeric acid, and octanoic acid separately using 1:1 molar ratio. The resulting esters were characterized using nuclear magnetic resonance spectroscopy (NMR), Fourier-transform infrared spectroscopy (FTIR), and thermal gravimetric analysis (TGA). The rheological properties were studied, and it was found that the prepared esters have high thermal stabilities as the degradation takes place in the range of 175ºC - 425ºC. The prepared esters show Newtonian behaviors as their viscosities do not change by changing shear rate. The physicochemical characteristic of prepared esters were also determined which showed improved low temperature properties (PP) -36ºC for ester (2R)-1,2-bis(2-ethylhexyl) 3-nonyl 2-(pentanoyloxy)propane-1,2,3-tricarboxylate (COEV) and viscosity index (VI) at 195 for ester (2R)-1-decyl 3-(2-ethylhexyl) 2-heptan-3-yl 2-(propionyloxy)propane-1,2,3-tricarboxylate (CDEP). The stabilities of the prepared esters were confirmed via the computational analysis and their stabilities were ranked as CDEP > COEP > COEO > COEV.Keywords: synthetic lubricantscitrate estersrheologyviscosity indexpour pointDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.","PeriodicalId":23315,"journal":{"name":"Tribology Transactions","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135994045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-11DOI: 10.1080/10402004.2023.2264908
Martin Rank, Manuel Oehler, Oliver Koch, Kirsten Bobzin, Christian Kalscheuer, Max P. Möbius
Physical vapor deposition (PVD) coatings are vital for enhancing wear resistance but face challenges in coating inaccessible surfaces due to their line-of-sight nature. A potential remedy is utilizing triboactive CrAlMoN coatings. These form a tribofilm in the contact zone when applied to one contact partner along with a suitable lubricant. This tribofilm can subsequently safeguard inaccessible yet tribologically stressed surfaces.
{"title":"Investigation of the Influence of Triboactive CrAlMoN Coating on the Joint Wear of Grease-lubricated Roller Chains","authors":"Martin Rank, Manuel Oehler, Oliver Koch, Kirsten Bobzin, Christian Kalscheuer, Max P. Möbius","doi":"10.1080/10402004.2023.2264908","DOIUrl":"https://doi.org/10.1080/10402004.2023.2264908","url":null,"abstract":"Physical vapor deposition (PVD) coatings are vital for enhancing wear resistance but face challenges in coating inaccessible surfaces due to their line-of-sight nature. A potential remedy is utilizing triboactive CrAlMoN coatings. These form a tribofilm in the contact zone when applied to one contact partner along with a suitable lubricant. This tribofilm can subsequently safeguard inaccessible yet tribologically stressed surfaces.","PeriodicalId":23315,"journal":{"name":"Tribology Transactions","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136097754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-01Epub Date: 2023-08-07DOI: 10.25259/JNRP_45_2023
Amit Kumar Thotakura, Kiran Chand Velivela, Nageswara Rao Marabathina, Abdul Aziz Riyaz, Siva Prabodh Vuddandi, Ankamma Rao Danaboyina
S100B is a biochemical marker of head injury and optic nerve sheath diameter (ONSD) is a non-invasive bedside technique to detect intracranial pressure. We aim to demonstrate whether ONSD correlates with S100B protein in head injury patients with contusions and also whether the grade of contusion correlates with S100B protein. This is a prospective study done on head injury patients aged between 18 and 75 years having isolated contusions admitted within 24 h of injury. Patients were assessed neurologically with Glasgow Coma Scale (GCS) and cranial computed tomography study on admission. Ocular sonography was done for ONSD recording, and S100B protein venous samples were collected at 24 h, 48 h, and at discharge. The outcome was evaluated with Glasgow Outcome Scale (GOS) at discharge and 3 months. Out of 42 patients, the mean age was 46.2 years and 27 were males. There were 12 patients with mild, 25 with moderate, and 5 patients with severe head injury. The mean GCS at 24 h was 12.35, the mean ONSD at 24 h was 3.9 mm, and the mean S100B at 24 h was 0.214 µg/L. There was a statistically significant correlation noted between mean S100B and contusion grade. A moderate positive correlation was noted between ONSD and S100B at 48 h in mild and moderate head injury groups. Favorable outcome (GOS 4,5) at 3 months can be predicted by GCS, contusion grade, and S100B values. Better GCS (14 and 15), focal contusion grade, and S100B values (<0.5 µg/L) predict good outcome. Although ONSD and S100B give important information in different scenarios, S100B gives better predictive information in patients with traumatic cerebral contusions.
Key message: S100 B and ONSD are simple biochemical and radiological investigations that can be done in every neurosurgical setup and can be useful in the management of head injury patients.
S100B是头部损伤的生化标志物，视神经鞘直径(ONSD)是一种检测颅内压的无创床边技术。我们的目的是证明ONSD是否与头部损伤挫伤患者的S100B蛋白相关，以及挫伤的程度是否与S100B蛋白相关。这是一项对年龄在18至75岁之间的头部损伤患者进行的前瞻性研究，这些患者在受伤后24小时内接受了孤立挫伤。入院时采用格拉斯哥昏迷评分(GCS)和颅脑ct检查对患者进行神经学评估。眼超声记录ONSD，并于24 h、48 h和出院时采集S100B蛋白静脉样本。在出院和3个月时用格拉斯哥预后量表(GOS)评估结果。42例患者平均年龄46.2岁，男性27例。轻度颅脑损伤12例，中度颅脑损伤25例，重度颅脑损伤5例。24 h时平均GCS为12.35,24 h时平均ONSD为3.9 mm, 24 h时平均S100B为0.214µg/L。平均S100B与挫伤程度有显著的统计学相关性。轻、中度脑损伤组48 h时ONSD与S100B呈中度正相关。GCS、挫伤等级和S100B值可预测3个月时的良好预后(GOS 4,5)。更好的GCS(14和15)、局灶性挫伤分级和S100B值(关键信息:S100B和ONSD是简单的生化和放射学检查，可在所有神经外科设置中进行，可用于头部损伤患者的管理。
{"title":"S100B and optic nerve sheath diameter correlation in head injury patients with contusions.","authors":"Amit Kumar Thotakura, Kiran Chand Velivela, Nageswara Rao Marabathina, Abdul Aziz Riyaz, Siva Prabodh Vuddandi, Ankamma Rao Danaboyina","doi":"10.25259/JNRP_45_2023","DOIUrl":"10.25259/JNRP_45_2023","url":null,"abstract":"<p><p>S100B is a biochemical marker of head injury and optic nerve sheath diameter (ONSD) is a non-invasive bedside technique to detect intracranial pressure. We aim to demonstrate whether ONSD correlates with S100B protein in head injury patients with contusions and also whether the grade of contusion correlates with S100B protein. This is a prospective study done on head injury patients aged between 18 and 75 years having isolated contusions admitted within 24 h of injury. Patients were assessed neurologically with Glasgow Coma Scale (GCS) and cranial computed tomography study on admission. Ocular sonography was done for ONSD recording, and S100B protein venous samples were collected at 24 h, 48 h, and at discharge. The outcome was evaluated with Glasgow Outcome Scale (GOS) at discharge and 3 months. Out of 42 patients, the mean age was 46.2 years and 27 were males. There were 12 patients with mild, 25 with moderate, and 5 patients with severe head injury. The mean GCS at 24 h was 12.35, the mean ONSD at 24 h was 3.9 mm, and the mean S100B at 24 h was 0.214 µg/L. There was a statistically significant correlation noted between mean S100B and contusion grade. A moderate positive correlation was noted between ONSD and S100B at 48 h in mild and moderate head injury groups. Favorable outcome (GOS 4,5) at 3 months can be predicted by GCS, contusion grade, and S100B values. Better GCS (14 and 15), focal contusion grade, and S100B values (<0.5 µg/L) predict good outcome. Although ONSD and S100B give important information in different scenarios, S100B gives better predictive information in patients with traumatic cerebral contusions.</p><p><strong>Key message: </strong>S100 B and ONSD are simple biochemical and radiological investigations that can be done in every neurosurgical setup and can be useful in the management of head injury patients.</p>","PeriodicalId":23315,"journal":{"name":"Tribology Transactions","volume":"20 1","pages":"599-602"},"PeriodicalIF":1.4,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10696316/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81661650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
AbstractFriction and wear seriously affect the efficiency and life of the machine device. The dynamic pressure lubrication and friction properties of the surface are improved by surface texture technology, which plays an extremely important role in reducing friction and wear. In order to maximize the hydrodynamic lubrication and friction reduction performance of surface texture, a Tesla valve surface texture is proposed in this paper. The oil film bearing capacity and wall friction of Tesla valve texture through CFD(Computational Fluid Dynamics) fluid simulation. Cylindrical rolls with Tesla valve texture are prepared by using the laser processing technology, and comparative friction wear tests are conducted. The results show that the lubrication performance of Tesla valve texture are 4 times higher than those of the non-texture; The friction coefficient and wear loss of the cylindrical rolls with Tesla valve texture are, respectively, 39.7% and 66.7% lower than those of the cylindrical rolls without texture. Tesla valve texture effectively improves the dynamic pressure lubrication and friction in the cylindrical rolls.Keywords: Tesla valveSurface textureDynamic pressure lubricationFriction reduction performanceDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.
{"title":"Study on hydrodynamic lubrication and friction reduction performance of cylindrical rolls with Tesla valve texture","authors":"Renqing Duoji, Xiayun Shu, Jingyu Mo, Bingjing Lin, Shanming Luo, Xuefeng Chang","doi":"10.1080/10402004.2023.2249955","DOIUrl":"https://doi.org/10.1080/10402004.2023.2249955","url":null,"abstract":"AbstractFriction and wear seriously affect the efficiency and life of the machine device. The dynamic pressure lubrication and friction properties of the surface are improved by surface texture technology, which plays an extremely important role in reducing friction and wear. In order to maximize the hydrodynamic lubrication and friction reduction performance of surface texture, a Tesla valve surface texture is proposed in this paper. The oil film bearing capacity and wall friction of Tesla valve texture through CFD(Computational Fluid Dynamics) fluid simulation. Cylindrical rolls with Tesla valve texture are prepared by using the laser processing technology, and comparative friction wear tests are conducted. The results show that the lubrication performance of Tesla valve texture are 4 times higher than those of the non-texture; The friction coefficient and wear loss of the cylindrical rolls with Tesla valve texture are, respectively, 39.7% and 66.7% lower than those of the cylindrical rolls without texture. Tesla valve texture effectively improves the dynamic pressure lubrication and friction in the cylindrical rolls.Keywords: Tesla valveSurface textureDynamic pressure lubricationFriction reduction performanceDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.","PeriodicalId":23315,"journal":{"name":"Tribology Transactions","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135538443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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